[Federal Register Volume 72, Number 15 (Wednesday, January 24, 2007)]
[Proposed Rules]
[Pages 3200-3344]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 07-110]
[[Page 3199]]
-----------------------------------------------------------------------
Part II
Environmental Protection Agency
-----------------------------------------------------------------------
40 CFR Part 86
Control of Air Pollution From New Motor Vehicles and New Motor Vehicle
Engines--Heavy-Duty Vehicle and Engine Standards; Onboard Diagnostic
Requirements; Proposed Rule
Federal Register / Vol. 72, No. 15 / Wednesday, January 24, 2007 /
Proposed Rules
[[Page 3200]]
-----------------------------------------------------------------------
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 86
[OAR-2005-0047; FRL-8256-9]
RIN 2060-AL92
Control of Air Pollution From New Motor Vehicles and New Motor
Vehicle Engines; Regulations Requiring Onboard Diagnostic Systems on
2010 and Later Heavy-Duty Engines Used in Highway Applications Over
14,000 Pounds; Revisions to Onboard Diagnostic Requirements for Diesel
Highway Heavy-Duty Vehicles Under 14,000 Pounds
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice of proposed rulemaking.
-----------------------------------------------------------------------
SUMMARY: In 2001, EPA finalized a new, major program for highway heavy-
duty engines. That program, the Clean Diesel Trucks and Buses program,
will result in the introduction of advanced emissions control systems
such as catalyzed diesel particulate filters (DPF) and catalysts
capable of reducing harmful nitrogen oxide (NOX) emissions.
This proposal would require that these advanced emissions control
systems be monitored for malfunctions via an onboard diagnostic system
(OBD), similar to those systems that have been required on passenger
cars since the mid-1990s. This proposal would require manufacturers to
install OBD systems that monitor the functioning of emission control
components and alert the vehicle operator to any detected need for
emission related repair. This proposal would also require that
manufacturers make available to the service and repair industry
information necessary to perform repair and maintenance service on OBD
systems and other emission related engine components. Lastly, this
proposal would revise certain existing OBD requirements for diesel
engines used in heavy-duty vehicles under 14,000 pounds.
DATES: If we do not receive a request for a public hearing, written
comments are due March 26, 2007. Requests for a public hearing must be
received by February 8, 2007. If we do receive a request for a public
hearing, we will publish a notice in the Federal Register and on the
Web at http://www.epa.gov/obd/regtech/heavy.htm containing details
regarding the location, date, and time of the public hearing. In that
case, the public comment period would close 30 days after the public
hearing. Under the Paperwork Reduction Act, comments on the information
collection provisions must be received by OMB on or before February 23,
2007.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2005-0047, by one of the following methods:
http://www.regulations.gov: Follow the on-line
instructions for submitting comments.
Mail: Onboard Diagnostic (OBD) Systems on 2010 and Later
Heavy-Duty Highway Vehicles and Engines, Environmental Protection
Agency, Mailcode: 6102T, 1200 Pennsylvania Ave., NW., Washington, DC,
20460, Attention Docket ID No. EPA-HQ-OAR-2005-0047. In addition,
please mail a copy of your comments on the information collection
provisions to the Office of Information and Regulatory Affairs, Office
of Management and Budget (OMB), Attn: Desk Officer for EPA, 725 17th
St. NW., Washington, DC 20503.
Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-
2005-0047. EPA's policy is that all comments received will be included
in the public docket without change and may be made available online at
http://www.regulations.gov, including any personal information
provided, unless the comment includes information claimed to be
Confidential Business Information (CBI) or other information whose
disclosure is restricted by statute. Do not submit information that you
consider to be CBI or otherwise protected through http://www.regulations.gov or e-mail. The http://www.regulations.gov Web site
is an ``anonymous access'' system, which means EPA will not know your
identity or contact information unless you provide it in the body of
your comment. If you send an e-mail comment directly to EPA without
going through http://www.regulations.gov your e-mail address will be
automatically captured and included as part of the comment that is
placed in the public docket and made available on the Internet. If you
submit an electronic comment, EPA recommends that you include your name
and other contact information in the body of your comment and with any
disk or CD-ROM you submit. If EPA cannot read your comment due to
technical difficulties and cannot contact you for clarification, EPA
may not be able to consider your comment. Electronic files should avoid
the use of special characters, any form of encryption, and be free of
any defects or viruses.
Docket: All documents in the docket are listed in the http://www.regulations.gov index. Although listed in the index, some
information is not publicly available, e.g., CBI or other information
whose disclosure is restricted by statute. Certain other material, such
as copyrighted material, will be publicly available only in hard copy.
Publicly available docket materials are available either electronically
in http://www.regulations.gov or in hard copy at the Air Docket, EPA/
DC, EPA West, Room B102, 1301 Constitution Ave., NW., Washington, DC.
The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday
through Friday, excluding legal holidays. The telephone number for the
Public Reading Room is (202) 566-1744, and the telephone number for the
Air Docket is (202) 566-1742.
Note: The EPA Docket Center suffered damage due to flooding
during the last week of June 2006. The Docket Center is continuing
to operate. However, during the cleanup, there will be temporary
changes to Docket Center telephone numbers, addresses, and hours of
operation for people who wish to make hand deliveries or visit the
Public Reading Room to view documents. Consult EPA's Federal
Register notice at 71 FR 38147 (July 5, 2006) or the EPA Web site at
http://www.epa.gov/epahome/dockets.htm for current information on
docket operations, locations and telephone numbers. The Docket
Center's mailing address for U.S. mail and the procedure for
submitting comments to www.regulations.gov are not affected by the
flooding and will remain the same.
FOR FURTHER INFORMATION CONTACT: U.S. EPA, National Vehicle and Fuel
Emissions Laboratory, Assessment and Standards Division, 2000
Traverwood Drive, Ann Arbor, MI 48105; telephone (734) 214-4405, fax
(734) 214-4816, email [email protected].
SUPPLEMENTARY INFORMATION:
Regulated Entities
This action will affect you if you produce or import new heavy-duty
engines which are intended for use in highway vehicles such as trucks
and buses, or produce or import such highway vehicles, or convert
heavy-duty vehicles or heavy-duty engines used in highway vehicles to
use alternative fuels.
The following table gives some examples of entities that may have
to follow the regulations. But because these are only examples, you
should carefully examine the regulations in 40 CFR part 86. If you have
questions, call the person listed in the FOR FURTHER INFORMATION
CONTACT section of this preamble:
[[Page 3201]]
----------------------------------------------------------------------------------------------------------------
Examples of potentially regulated
Category NAICS Codes\a\ SIC Codes\b\ entities
----------------------------------------------------------------------------------------------------------------
Industry................................... 336111 3711 Motor Vehicle Manufacturers; Engine
336112 and Truck Manufacturers.
336120
Industry................................... 811112 7533 Commercial Importers of Vehicles
811198 7549 and Vehicle Components.
541514 8742
Industry................................... 336111 3592 Alternative fuel vehicle
converters.
336312 3714
422720 5172
454312 5984
811198 7549
541514 8742
541690 8931
----------------------------------------------------------------------------------------------------------------
\a\North American Industry Classification Systems (NAICS).
\b\Standard Industrial Classification (SIC) system code.
What Should I Consider as I Prepare My Comments for EPA?
Submitting CBI. Do not submit this information to EPA through
www.regulations.gov or e-mail. Clearly mark the part or all of the
information that you claim to be CBI. For CBI information in a disk or
CD ROM that you mail to EPA, mark the outside of the disk or CD ROM as
CBI and then identify electronically within the disk or CD ROM the
specific information that is claimed as CBI). In addition to one
complete version of the comment that includes information claimed as
CBI, a copy of the comment that does not contain the information
claimed as CBI must be submitted for inclusion in the public docket.
Information so marked will not be disclosed except in accordance with
procedures set forth in 40 CFR part 2.
Tips for Preparing Your Comments. When submitting comments,
remember to:
Identify the rulemaking by docket number and other
identifying information (subject heading, Federal Register date and
page number).
Follow directions--The agency may ask you to respond to
specific questions or organize comments by referencing a Code of
Federal Regulations (CFR) part or section number.
Explain why you agree or disagree; suggest alternatives
and substitute language for your requested changes.
Describe any assumptions and provide any technical
information and/or data that you used.
If you estimate potential costs or burdens, explain how
you arrived at your estimate in sufficient detail to allow for it to be
reproduced.
Provide specific examples to illustrate your concerns, and
suggest alternatives.
Explain your views as clearly as possible, avoiding the
use of profanity or personal threats.
Make sure to submit your comments by the comment period
deadline identified.
Outline of this Preamble
I. Overview
A. Background
B. What Is EPA Proposing?
1. OBD Requirements for Engines Used in Highway Vehicles Over
14,000 Pounds GVWR
2. Requirements That Service Information Be Made Available
3. OBD Requirements for Diesel Heavy-Duty Vehicles and Engines
Used in Vehicles Under 14,000 Pounds
C. Why Is EPA Making This Proposal?
1. Highway Engines and Vehicles Contribute to Serious Air
Pollution Problems
2. Emissions Control of Highway Engines and Vehicles Depends on
Properly Operating Emissions Control Systems
3. Basis for Action Under the Clean Air Act
D. How Has EPA Chosen the Level of the Proposed Emissions
Thresholds?
E. World Wide Harmonized OBD (WWH-OBD)
F. Onboard Diagnostics for Diesel Engines Used in Nonroad Land-
Based Equipment
1. What Is the Baseline Nonroad OBD System?
2. What Is The Appropriate Level of OBD Monitoring for Nonroad
Diesel Engines?
3. What Should the OBD Standardization Features Be?
4. What Are the Prospects and/or Desires for International
Harmonization of Nonroad OBD?
II. What Are the Proposed OBD Requirements and When Would They Be
Implemented?
A. General OBD System Requirements
1. The OBD System
2. Malfunction Indicator Light (MIL) and Diagnostic Trouble
Codes (DTC)
3. Monitoring Conditions
4. Determining the Proper OBD Malfunction Criteria
B. Monitoring Requirements and Timelines for Diesel-Fueled/
Compression-Ignition Engines
1. Fuel System Monitoring
2. Engine Misfire Monitoring
3. Exhaust Gas Recirculation (EGR) System Monitoring
4. Turbo Boost Control System Monitoring
5. Non-Methane Hydrocarbon (NMHC) Converting Catalyst Monitoring
6. Selective Catalytic Reduction (SCR) and Lean NOX
Catalyst Monitoring
7. NOX Adsorber System Monitoring
8. Diesel Particulate Filter (DPF) System Monitoring
9. Exhaust Gas Sensor Monitoring
C. Monitoring Requirements and Timelines for Gasoline/Spark-
Ignition Engines
1. Fuel System Monitoring
2. Engine Misfire Monitoring
3. Exhaust Gas Recirculation (EGR) Monitoring
4. Cold Start Emission Reduction Strategy Monitoring
5. Secondary Air System Monitoring
6. Catalytic Converter Monitoring
7. Evaporative Emission Control System Monitoring
8. Exhaust Gas Sensor Monitoring
D. Monitoring Requirements and Timelines for Other Diesel and
Gasoline Systems
1. Variable Valve Timing and/or Control (VVT) System Monitoring
2. Engine Cooling System Monitoring
3. Crankcase Ventilation System Monitoring
4. Comprehensive Component Monitors
5. Other Emissions Control System Monitoring
6. Exceptions to Monitoring Requirements
E. A Standardized Method To Measure Real World Monitoring
Performance
1. Description of Software Counters To Track Real World
Performance
2. Proposed Performance Tracking Requirements
F. Standardization Requirements
1. Reference Documents
2. Diagnostic Connector Requirements
3. Communications to a Scan Tool
4. Required Emissions Related Functions
5. In-Use Performance Ratio Tracking Requirements
6. Exceptions to Standardization Requirements
G. Implementation Schedule, In-Use Liability, and In-Use
Enforcement
1. Implementation Schedule and In-Use Liability Provisions
2. In-Use Enforcement
H. Proposed Changes to the Existing 8,500 to 14,000 Pound Diesel
OBD Requirements
[[Page 3202]]
1. Selective Catalytic Reduction and Lean NOX
Catalyst Monitoring
2. NOX Adsorber System Monitoring
3. Diesel Particulate Filter System Monitoring
4. NMHC Converting Catalyst Monitoring
5. Other Monitors
6. CARB OBDII Compliance Option and Deficiencies
I. How Do the Proposed Requirements Compare to California's?
III. Are the Proposed Monitoring Requirements Feasible?
A. Feasibility of the Monitoring Requirements for Diesel/
Compression-Ignition Engines
1. Fuel System Monitoring
2. Engine Misfire Monitoring
3. Exhaust Gas Recirculation (EGR) Monitoring
4. Turbo Boost Control System Monitoring
5. Non-Methane Hydrocarbon (NMHC) Converting Catalyst Monitoring
6. Selective Catalytic Reduction (SCR) and NOX
Conversion Catalyst Monitoring
7. NOX Adsorber Monitoring
8. Diesel Particulate Filter (DPF) Monitoring
9. Exhaust Gas Sensor Monitoring
B. Feasibility of the Monitoring Requirements for Gasoline/
Spark-Ignition Engines
1. Fuel System Monitoring
2. Engine Misfire Monitoring
3. Exhaust Gas Recirculation (EGR) Monitoring
4. Cold Start Emission Reduction Strategy Monitoring
5. Secondary Air System Monitoring
6. Catalytic Converter Monitoring
7. Evaporative System Monitoring
8. Exhaust Gas Sensor Monitoring
C. Feasibility of the Monitoring Requirements for Other Diesel
and Gasoline Systems
1. Variable Valve Timing and/or Control (VVT) System Monitoring
2. Engine Cooling System Monitoring
3. Crankcase Ventilation System Monitoring
4. Comprehensive Component Monitoring
IV. What Are the Service Information Availability Requirements?
A. What Is the Important Background Information for the Proposed
Service Information Provisions?
B. How Do the Below 14,000 Pound and Above 14,000 Pounds
Aftermarket Service Industry Compare?
C. What Provisions Are Being Proposed for Service Information
Availability?
1. What Information Is Proposed To Be Made Available by OEMs?
2. What Are the Proposed Requirements for Web-Based Delivery of
the Required Information?
3. What Provisions Are Being Proposed for Service Information
for Third Party Information Providers?
4. What Requirements Are Being Proposed for the Availability of
Training Information?
5. What Requirements Are Being Proposed for Reprogramming of
Vehicles?
6. What Requirements Are Being Proposed for the Availability of
Enhanced Information for Scan Tools for Equipment and Tool
Companies?
7. What Requirements Are Being Proposed for the Availability of
OEM--Specific Diagnostic Scan Tools and Other Special Tools?
8. Which Reference Materials Are Being Proposed for
Incorporation by Reference?
V. What Are the Emissions Reductions Associated With the Proposed
OBD Requirements?
VI. What Are the Costs Associated With the Proposed OBD
Requirements?
A. Variable Costs for Engines Used in Vehicles Over 14,000
Pounds
B. Fixed Costs for Engines Used in Vehicles Over 14,000 Pounds
C. Total Costs for Engines Used in Vehicles Over 14,000 Pounds
D. Costs for Diesel Heavy-Duty Vehicles and Engines Used in
Heavy-Duty Vehicles Under 14,000 Pounds
VII. What are the Updated Annual Costs and Costs per Ton Associated
With the 2007/2010 Heavy-Duty Highway Program?
A. Updated 2007 Heavy-Duty Highway Rule Costs Including OBD
B. Updated 2007 Heavy-Duty Highway Rule Costs Per Ton Including
OBD
VIII. What Are the Requirements for Engine Manufacturers?
A. Documentation Requirements
B. Catalyst Aging Procedures
C. Demonstration Testing
1. Selection of Test Engines
2. Required Testing
3. Testing Protocol
4. Evaluation Protocol
5. Confirmatory Testing
D. Deficiencies
E. Production Evaluation Testing
1. Verification of Standardization Requirements
2. Verification of Monitoring Requirements
3. Verification of In-Use Monitoring Performance Ratios
IX. What Are the Issues Concerning Inspection and Maintenance
Programs?
A. Current Heavy-Duty I/M Programs
B. Challenges for Heavy-Duty I/M
C. Heavy-Duty OBD and I/M
X. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review
B. Paperwork Reduction Act
C. Regulatory Flexibility Act (RFA), as Amended by the Small
Business Regulatory Enforcement Fairness Act of 1996 (SBREFA), 5
U.S.C. 601 et. seq.
D. Unfunded Mandates Reform Act
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
G. Executive Order 13045: Protection of Children From
Environmental Health and Safety Risks
H. Executive Order 13211: Actions That Significantly Affect
Energy Supply, Distribution, or Use
I. National Technology Transfer Advancement Act
XI. Statutory Provisions and Legal Authority
I. Overview
A. Background
Section 202(m) of the CAA, 42 U.S.C. 7521(m), directs EPA to
promulgate regulations requiring 1994 and later model year light-duty
vehicles (LDVs) and light-duty trucks (LDTs) to contain an OBD system
that monitors emission-related components for malfunctions or
deterioration ``which could cause or result in failure of the vehicles
to comply with emission standards established'' for such vehicles.
Section 202(m) also states that, ``The Administrator may, in the
Administrator's discretion, promulgate regulations requiring
manufacturers to install such onboard diagnostic systems on heavy-duty
vehicles and engines.''
On February 19, 1993, we published a final rule requiring
manufacturers of light-duty applications to install such OBD systems on
their vehicles beginning with the 1994 model year (58 FR 9468). The OBD
systems must monitor emission control components for any malfunction or
deterioration that could cause exceedance of certain emission
thresholds. The regulation also required that the driver be notified of
any need for repair via a dashboard light, or malfunction indicator
light (MIL), when the diagnostic system detected a problem. We also
allowed optional compliance with California's second phase OBD
requirements, referred to as OBDII (13 CCR 1968.1), for purposes of
satisfying the EPA OBD requirements. Since publishing the 1993 OBD
final rule, EPA has made several revisions to the OBD requirements,
most of which served to align the EPA OBD requirements with revisions
to the California OBDII requirements (13 CCR 1968.2).
On August 9, 1995, EPA published a final rulemaking that set forth
service information regulations for light-duty vehicles and light-duty
trucks (60 FR 40474). These regulations, in part, required each
Original Equipment Manufacturer (OEM) to do the following: (1) List all
of its emission-related service and repair information on a Web site
called FedWorld (including the cost of each item and where it could be
purchased); (2) either provide enhanced information to equipment and
tool companies or make its OEM-specific diagnostic tool available for
purchase by aftermarket technicians, and (3) make reprogramming
capability available to independent service and repair professionals if
its franchised dealerships had such capability. These requirements are
intended to ensure that aftermarket service and repair facilities
[[Page 3203]]
have access to the same emission-related service information, in the
same or similar manner, as that provided by OEMs to their franchised
dealerships. These service information availability requirements have
been revised since that first final rule in response to changing
technology among other reasons. (68 FR 38428)
In October of 2000, we published a final rule requiring OBD systems
on heavy-duty vehicles and engines up to 14,000 pounds GVWR (65 FR
59896). In that rule, we expressed our intention of developing OBD
requirements in a future rule for vehicles and engines used in vehicles
over 14,000 pounds. We expressed this same intention in our 2007HD
highway final rule (66 FR 5002) which established new heavy-duty
highway emissions standards for 2007 and later model year engines. In
June of 2003, we published a final rule extending service information
availability requirements to heavy-duty vehicles and engines weighing
up to 14,000 pounds GVWR. We declined extending these requirements to
engines above 14,000 pounds GVWR at least until such engines are
subject to OBD requirements.
On January 18, 2001, EPA established a comprehensive national
control program--the Clean Diesel Truck and Bus program--that regulates
the heavy-duty vehicle and its fuel as a single system. (66 FR 5002) As
part of this program, new emission standards will begin to take effect
in model year 2007 and will apply to heavy-duty highway engines and
vehicles. These standards are based on the use of high-efficiency
catalytic exhaust emission control devices or comparably effective
advanced technologies. Because these devices are damaged by sulfur, the
regulation also requires the level of sulfur in highway diesel fuel be
reduced by 97 percent.\1\
---------------------------------------------------------------------------
\1\ Note that the 2007HD highway rule contained new emissions
standards for gasoline engines as well as diesel engines.
---------------------------------------------------------------------------
Today's action proposes new OBD requirements for highway engines
used in vehicles greater than 14,000 pounds. Today's action also
proposes new availability requirements for emission-related service
information that will make this information more widely available to
the industry servicing vehicles over 14,000 pounds.
In addition to these proposed requirements and changes, we are
seeking comment on possible future regulations that would require OBD
systems on heavy-duty diesel engines used in nonroad equipment. Diesel
engines used in nonroad equipment are, like highway engines, a major
source of NOX and particulate matter (PM) emissions, and the
diesel engines used in nonroad equipment are essentially the same as
those used in heavy-duty highway trucks. Further, new regulations
applicable to nonroad diesel engines will result in the introduction of
advanced emissions control systems like those expected for highway
diesel engines. (69 FR 38958) Therefore, having OBD systems and OBD
regulations for nonroad engines seems to be a natural progression from
the proposed requirements for heavy-duty highway engines. We discuss
this issue in greater detail in section I of this preamble with the
goal of soliciting public comment regarding how we should proceed with
respect to nonroad OBD.
B. What Is EPA Proposing?
1. OBD Requirements for Engines Used in Highway Vehicles Over 14,000
Pounds GVWR
We believe that OBD requirements should be extended to include over
14,000 pound heavy-duty vehicles and engines for many reasons. In the
past, heavy-duty diesel engines have relied primarily on in-cylinder
modifications to meet emission standards. For example, emission
standards have been met through changes in fuel timing, piston design,
combustion chamber design, charge air cooling, use of four valves per
cylinder rather than two valves, and piston ring pack design and
location improvements. In contrast, the 2004 and 2007 emission
standards represent a different sort of technological challenge that
are being met with the addition of exhaust gas recirculation (EGR)
systems and the addition of exhaust aftertreatment devices such as
diesel particulate filters (DPF), sometimes called PM traps, and
NOX catalysts. Such ``add on'' devices can experience
deterioration and malfunction that, unlike the engine design elements
listed earlier, may go unnoticed by the driver. Because deterioration
and malfunction of these devices can go unnoticed by the driver, and
because their primary purpose is emissions control, and because the
level of emission control is on the order of 50 to 99 percent, some
form of diagnosis and malfunction detection is crucial. We believe that
such detection can be effectively achieved by employing a well designed
OBD system.
The same is true for gasoline heavy-duty vehicles and engines.
While emission control is managed with both engine design elements and
aftertreatment devices, the catalytic converter is the primary emission
control feature accounting for over 95 percent of the emission control.
We believe that monitoring the emission control system for proper
operation is critical to ensure that new vehicles and engines certified
to the very low emission standards set in recent years continue to meet
those standards throughout their full useful life.
Further, the industry trend is clearly toward increasing use of
computer and electronic controls for both engine and powertrain
management, and for emission control. In fact, the heavy-duty industry
has already gone a long way, absent any government regulation, to
standardize computer communication protocols.\2\ Computer and
electronic control systems, as opposed to mechanical systems, provide
improvements in many areas including, but not limited to, improved
precision and control, reduced weight, and lower cost. However,
electronic and computer controls also create increased difficulty in
diagnosing and repairing the malfunctions that inevitably occur in any
engine or powertrain system. Today's proposed OBD requirements would
build on the efforts already undertaken by the industry to ensure that
key emissions related components will be monitored in future heavy-duty
vehicles and engines and that the diagnosis and repair of those
components will be as efficient and cost effective as possible.
---------------------------------------------------------------------------
\2\ See ``On-Board Diagnostics, A Heavy-Duty Perspective,'' SAE
951947; ``Recommended Practice for a Serial Control and
Communications Vehicle Network,'' SAE J1939 which may be obtained
from Society of Automotive Engineers International, 400 Commonwealth
Dr., Warrendale, PA, 15096-0001; and ``Road Vehicles-Diagnostics on
Controller Area Network (CAN)--Part 4: Requirements for emission-
related systems,'' ISO 15765-4:2001 which may be obtained from the
International Organization for Standardization, Case Postale 56, CH-
1211 Geneva 20, Switzerland.
---------------------------------------------------------------------------
Lastly, heavy-duty engines and, in particular, diesel engines tend
to have very long useful lives. With age comes deterioration and a
tendency toward increasing emissions. With the OBD systems proposed
today, we expect that these engines will continue to be properly
maintained and therefore will continue to emit at low emissions levels
even after accumulating hundreds of thousands and even a million miles.
For the reasons laid out above, most manufacturers of vehicles,
trucks, and engines have incorporated some type of OBD system into
their products that are capable of identifying when certain types of
malfunctions occur, and in what systems. In the heavy-duty industry,
those OBD systems traditionally have been geared toward
[[Page 3204]]
detecting malfunctions causing drivability and/or fuel economy related
problems. Without specific requirements for manufacturers to include
OBD mechanisms to detect emission-related problems, those types of
malfunctions that could result in high emissions without a
corresponding adverse drivability or fuel economy impact could go
unnoticed by both the driver and the repair technician. The resulting
increase in emissions and detrimental impact on air quality could be
avoided by incorporating an OBD system capable of detecting emission
control system malfunctions.
2. Requirements That Service Information Be Made Available
We are proposing that makers of engines that go into vehicles over
14,000 pounds make available to any person engaged in repair or service
all information necessary to make use of the OBD systems and for making
emission-related repairs, including any emissions-related information
that is provided by the OEM to franchised dealers. This information
includes, but is not limited to, manuals, technical service bulletins
(TSBs), a general description of the operation of each OBD monitor,
etc. We discuss the proposed requirements further in section IV of this
preamble.
The proposed requirements are similar to those required currently
for all 1996 and newer light-duty vehicles and light-duty trucks and
2005 and newer heavy-duty applications up to 14,000 pounds. While EPA
understands that there may be some differences between aftermarket
service for the under 14,000 pound and over 14,000 pound applications,
we believe that any such differences would not substantially affect the
implementation of such requirements and that, therefore, it is
reasonable to use EPA's existing service information regulations as a
basis for proposing service information requirements for the over
14,000 pound arena. See section IV for a complete discussion of the
service information provisions being proposed for the availability of
over 14,000 pound service information.
Note that information for making emission-related repairs does not
include information used to design and manufacture parts, but it may
include OEM changes to internal calibrations and other indirect
information, as discussed in section IV.
3. OBD Requirements for Diesel Heavy-Duty Vehicles and Engines Used in
Vehicles Under 14,000 Pounds
We are also proposing some changes to the existing diesel OBD
requirements for heavy-duty applications under 14,000 pounds (i.e.,
8,500 to 14,000 pounds). Some of these changes are being proposed for
the 2007 and later model years (i.e., for immediate implementation)
because we believe that some of the requirements that we currently have
in place for 8,500 to 14,000 pound applications cannot be met by
diesels without granting widespread deficiencies to industry. Other
changes are being proposed for the 2010 and later model years since
they represent an increase in the stringency of our current OBD
requirements and, therefore, some leadtime is necessary for
manufacturers to comply. All of the changes being proposed for 8,500 to
14,000 pound diesel applications would result in OBD emissions
thresholds identical, for all practical purposes, to the OBD thresholds
being proposed for over 14,000 pound applications.
C. Why Is EPA Making This Proposal?
1. Highway Engines and Vehicles Contribute to Serious Air Pollution
Problems
The pollution emitted by heavy-duty highway engines contributes
greatly to our nation's continuing air quality problems. Our 2007HD
highway rule was designed to address these serious air quality
problems. These problems include premature mortality, aggravation of
respiratory and cardiovascular disease, aggravation of existing asthma,
acute respiratory symptoms, chronic bronchitis, and decreased lung
function. Numerous studies also link diesel exhaust to increased
incidence of lung cancer. We believe that diesel exhaust is likely to
be carcinogenic to humans by inhalation and that this cancer hazard
exists for occupational and environmental levels of exposure.
Our 2007HD highway rule will regulate the heavy-duty vehicle and
its fuel as a single system. As part of this program, new emission
standards will begin to take effect in model year 2007 and phase-in
through model year 2010, and will apply to heavy-duty highway engines
and vehicles. These standards are based on the use of high-efficiency
catalytic exhaust emission control devices or comparably effective
advanced technologies and a cap on the allowable sulfur content in both
diesel fuel and gasoline.
In the 2007HD highway final rule, we estimated that, by 2007,
heavy-duty trucks and buses would account for about 28 percent of
nitrogen oxides emissions and 20 percent of particulate matter
emissions from mobile sources. In some urban areas, the contribution is
even greater. The 2007HD highway program will reduce particulate matter
and oxides of nitrogen emissions from heavy-duty engines by 90 percent
and 95 percent below current standard levels, respectively. In order to
meet these more stringent standards for diesel engines, the program
calls for a 97 percent reduction in the sulfur content of diesel fuel.
As a result, diesel vehicles will achieve gasoline-like exhaust
emission levels. We have also established more stringent standards for
heavy-duty gasoline vehicles, based in part on the use of the low
sulfur gasoline that will be available when the standards go into
effect.
2. Emissions Control of Highway Engines and Vehicles Depends on
Properly Operating Emissions Control Systems
The emissions reductions and resulting health and welfare benefits
of the 2007HD highway program will be dramatic when fully implemented.
By 2030, the program will reduce annual emissions of nitrogen oxides,
nonmethane hydrocarbons, and particulate matter by a projected 2.6
million, 115,000 and 109,000 tons, respectively. However, to realize
those large emission reductions and health benefits, the emission
control systems on heavy-duty highway engines and vehicles must
continue to provide the 90 to 95 percent emission control effectiveness
throughout their operating life. Today's proposed OBD requirements will
help to ensure that emission control systems continue to operate
properly by detecting when those systems malfunction, by then notifying
the driver that a problem exists that requires service and, lastly, by
informing the service technician what the problem is so that it can be
properly repaired.
3. Basis for Action Under the Clean Air Act
Section 202(m) of the CAA, 42 U.S.C. 7521(m), directs EPA to
promulgate regulations requiring 1994 and later model year light-duty
vehicles (LDVs) and light-duty trucks (LDTs) to contain an OBD system
that monitors emission-related components for malfunctions or
deterioration ``which could cause or result in failure of the vehicles
to comply with emission standards established'' for such vehicles.
Section
[[Page 3205]]
202(m) also states that, ``The Administrator may, in the
Administrator's discretion, promulgate regulations requiring
manufacturers to install such onboard diagnostic systems on heavy-duty
vehicles and engines.''
Section 202(m)(5) of the CAA states that the Administrator shall
require manufacturers to, ``provide promptly to any person engaged in
the repairing or servicing of motor vehicles or motor vehicle engines *
* * with any and all information needed to make use of the emission
control diagnostics system prescribed under this subsection and such
other information including instructions for making emission related
diagnosis and repairs.''
D. How Has EPA Chosen the Level of the Proposed Emissions Thresholds?
The OBD emissions thresholds that we are proposing are summarized
in Tables II.B-1, II.C-1, II.H-1 and II.H-2. These tables show the
actual threshold levels and how they relate to current emissions
standards. Here, we wish to summarize how we chose those proposed
thresholds. First, it is important to note that OBD is more than
emissions thresholds. In fact, most OBD monitors are not actually tied
to an emissions threshold. Instead, they monitor the performance of a
given component or system and evaluate that performance based on
electrical information (e.g., voltage within proper range) or
temperature information (e.g., temperature within range), etc. Such
monitors often detect malfunctions well before emissions are seriously
compromised. Nonetheless, emissions thresholds are a critical element
to OBD requirements since some components and systems, most notably any
aftertreatment devices, cannot be monitored in simple electrical or
temperature related terms. Instead, their operating characteristics can
be measured and correlated to an emissions impact. This way, when those
operating characteristics are detected, an unacceptable emissions
increase can be inferred and a malfunction can be noted to the driver.
Part of the challenge in establishing OBD requirements is
determining the point--the OBD threshold--at which an unacceptable
emissions increase has occurred that is detectable by the best
available OBD technology. Two factors have gone into our determination
of the emissions thresholds we are proposing: technological
feasibility; and the costs and emissions reductions associated with
repairs initiated as a result of malfunctions found by OBD systems. The
first of these factors is discussed in more detail in section III where
we present our case for the technological feasibility of the
thresholds. In summary, we believe that the thresholds we are proposing
are, while challenging, technologically feasible in the 2010 and later
timeframe. We have carefully considered monitoring system capability,
sensor capability, emissions measurement capability, test-to-test
variability and, perhaps most importantly, the manufacturers'
engineering and test cell resources and have arrived at thresholds we
believe can be met on one engine family per manufacturer in the 2010
model year and on all engine families by the 2013 model year.
We believe that the proposed thresholds strike the proper balance
between environmental protection, OBD and various sensor capabilities,
and avoidance of repairs whose costs could be high compared to their
emission control results. One must keep in mind that increasingly
stringent OBD thresholds (i.e., OBD detection at lower emissions
levels) may lead to more durable emission controls due to a
manufacturer's desire to avoid the negative impression given their
product upon an OBD detection. Such an outcome would result in lower
fleetwide emissions while increasing costs to manufacturers. However,
increasingly stringent OBD thresholds may also lead to more OBD
detections and more OBD induced repairs and, perhaps, many OBD induced
repairs for malfunctions having little impact on emissions. Such an
outcome would result in lower fleetwide emissions while increasing
costs to both manufacturers and truck owners.
E. World Wide Harmonized OBD (WWH-OBD)
Within the United Nations (UN), the World Forum for Harmonization
of Vehicle Regulations (WP.29) administers the 1958 Geneva Agreement
(1958 Agreement) to facilitate the adoption of uniform conditions of
approval and reciprocal recognition of approval for motor vehicle
equipment and parts. As a result, WP.29 has responsibility for vehicle
regulations within Europe and, indirectly, many countries outside of
Europe that have voluntarily adopted the WP.29 regulations. The United
States was never a party to the 1958 Agreement, but EPA has monitored
the WP.29 regulations developed under the 1958 Agreement and we have
benefited from a reciprocal consultative relationship with our European
counterparts. More recently, WP.29 took on the responsibility of
administering the 1998 Global Agreement that established a process to
permit all regions of the world to jointly develop global technical
regulations without required mutual recognition of approvals or
designated compliance and enforcement. The United States is a signatory
of the 1998 Global Agreement (1998 Agreement), and EPA has
responsibility for representing the U.S. with respect to environmental
issues within WP.29 as they pertain to the 1998 Agreement.
During the one-hundred-and-twenty-sixth session of WP.29 of March
2002, the Executive Committee (AC.3) of the 1998 Global Agreement (1998
Agreement) adopted a Programme of Work, which includes the development
of a Global Technical Regulation (GTR) concerning onboard diagnostic
systems for heavy-duty vehicles and engines. An informal working
group--the WWH-OBD working group--was established to develop the GTR.
The working group was instructed that the OBD system should detect
failures from the engine itself, as well as from the exhaust
aftertreatment systems fitted downstream of the engine, and from the
package of information exchanged between the engine electronic control
unit(s) and the rest of vehicle and/or powertrain. The working group
was also instructed to base the OBD requirements on the technologies
expected to be industrially available at the time the GTR would be
enforced, and to take into account both the expected state of
electronics in the years 2005-2008 and the expected newest engine and
aftertreatment technologies.
In November 2003, AC.3 further directed the working group to
structure the GTR in such a manner as to enable its future extension to
other functions of the vehicle. In so doing, AC.3 did not revise the
scope of the task given to the working group (i.e., the scope remained
emissions-related heavy-duty OBD). As a result, the GTR is structured
such that OBD monitoring and communications could be extended to other
systems such as vehicle safety systems. This has been achieved by
dividing the GTR into a set of generic OBD requirements to be followed
by specific OBD requirements concerning any future desired OBD systems.
The generic OBD requirements contain definitions and other OBD
regulatory elements that are meant to be applicable throughout the GTR
and all of its modules, annexes, and appendices. This generic section
is followed by the first specific OBD section--emission-related OBD--
which contains definitions and OBD regulatory elements specific to
emissions-related OBD.
EPA has been active in the WWH-OBD working group for more than
three
[[Page 3206]]
years. Because that group has been developing a regulation at the same
time that we have been developing the requirements in this proposal,
our proposed OBD requirements are consistent, for the most part, with
the current efforts of the WWH-OBD group.
The WWH-OBD working group submitted a draft GTR as a formal
document in March of 2006. During the months immediately following, the
WWH-OBD working group has made final revisions to the GTR and will
submit it to WP.29 for consideration. If approved by WP.29 and adopted
as a formal global technical regulation, we would intend to propose any
revisions to our OBD regulations that might be necessary to make them
consistent with WWH-OBD.\3\
---------------------------------------------------------------------------
\3\ Note that, while the WWH-OBD GTR is consistent with many of
the specific requirements we are proposing, it is not currently as
comprehensive as our proposal (e.g., it does not contain the same
level of detail with respect to certification requirements and
enforcement provisions). For that reason, at this time, we do not
believe that the GTR would fully replace what we are proposing
today.
---------------------------------------------------------------------------
The latest version of the draft WWH-OBD GTR has been placed in the
docket for this rule.\4\ While it is not yet a final document, we are
nonetheless interested in comments regarding the current version. More
specifically, we are interested in comments regarding any possible
inconsistencies between the requirements of the draft GTR and the
requirements being proposed today. We believe that if such
inconsistencies exist, they are minor. WWH-OBD provides a framework for
nations to establish a heavy-duty OBD program. It has the potential to
result in similar OBD systems, but the WWH-OBD GTR must fit into the
context of any country's existing heavy-duty emissions regulations. For
example, at this time, the draft GTR does not specify emissions
threshold levels, implementation dates, or phase-in schedules. As such,
our proposal today is much more detailed than the draft WWH-OBD GTR,
but we believe there exist no major inconsistencies between the two
regulations.
---------------------------------------------------------------------------
\4\ ``Revised Proposal for New Draft Global Technical Regulation
(gtr): Technical Requirements for On-Board Diagnostic Systems (OBD)
for Road Vehicles;'' ECE/TRANS/WP.29/GRPE/2006/8/Rev.1; March 27,
2006, Docket ID EPA-HQ-OAR-2005-0047-0004.
---------------------------------------------------------------------------
F. Onboard Diagnostics for Diesel Engines Used in Nonroad Land-Based
Equipment
We are also considering regulations--although we are not making any
proposals today--that would require OBD systems on heavy-duty diesel
engines used in nonroad land-based equipment. The pollution emitted by
diesel nonroad engines contributes greatly to our nation's continuing
air quality problems. Our recent Nonroad Tier 4 rulemaking was designed
to address these serious air quality problems from land-based diesel
engines. (69 FR 38958) Like with diesel highway emissions, these
problems include premature mortality, aggravation of respiratory and
cardiovascular disease, aggravation of existing asthma, acute
respiratory symptoms, chronic bronchitis, and decreased lung function.
And, as noted above, we believe that diesel exhaust is likely to be
carcinogenic to humans by inhalation and that this cancer hazard exists
for occupational and environmental levels of exposure.
In our preamble to the Nonroad Tier 4 final rule, we estimated
that, absent the nonroad Tier 4 standards, by 2020, land based nonroad
diesel engines would account for as much as 70 percent of the diesel
mobile source PM inventory. As part of our nonroad Tier 4 program, new
emission standards will begin to take effect in calendar year 2011 that
are based on the use of high-efficiency catalytic exhaust emission
control devices or comparably effective advanced technologies. As with
our 2007HD highway program, a cap is also included on the allowable
sulfur content in nonroad diesel fuel.
The diesel engines used in nonroad land-based equipment are, in
certain horsepower ranges, often essentially the same as those used in
heavy-duty highway trucks. In other horsepower ranges--e.g., very large
nonroad machines with engines having more than 1,500 horsepower--the
engine is quite different. Such differences can include the addition of
cylinders and turbo chargers among other things. Notably, the new
nonroad Tier 4 regulations will result in the introduction of advanced
emissions control systems on nonroad land-based equipment; those
advanced emissions control systems will be the same type of systems as
those expected for highway diesel engines.
Therefore, having OBD systems and OBD regulations for nonroad
diesel engines seems to be a natural progression from the proposed
requirements for heavy-duty highway engines. Nonetheless, we believe
that there are differences between nonroad equipment and highway
applications, and differences between the nonroad market and the
highway market such that proposing the same OBD requirements for
nonroad as for highway may not be appropriate. Therefore, we are
providing advance notice to the public with the goal of soliciting
public comment regarding how we should proceed with respect to nonroad
OBD. This section presents issues we have identified and solicits
comment. We also welcome comment with respect to other issues we have
not addressed here, such as service information availability.
1. What Is the Baseline Nonroad OBD System?
We know that highway diesel engines already use a sophisticated
level of OBD system. For nonroad diesel engines in the 200 to 600
horsepower range--i.e., the typical range of highway engines--are the
current OBD system identical to their highway counterparts? How would
the proposed highway OBD requirements change this, if at all? Do diesel
engines outside the range typical of highway engines use OBD?
2. What Is the Appropriate Level of OBD Monitoring for Nonroad Diesel
Engines?
The proposed OBD requirements for highway engines are very
comprehensive and would result in virtually every element of the
emissions control system being monitored. Is this appropriate for
nonroad diesel engines? And to what degree should such monitoring be
required? The emissions thresholds proposed for highway engines will
push OBD and sensor technology beyond where it is today because of
their stringency. Is a similar level of stringency appropriate for
nonroad engines? Should emissions thresholds analogous to those
presented in Table II.B-1 of this preamble even be a part of any
potential nonroad OBD requirements or should nonroad OBD rely more
heavily on comprehensive component monitoring as discussed in section
II.D.4 of this preamble? This latter question is particularly
compelling given the incredibly broad range of operating
characteristics for nonroad equipment. Similar to the issue of
emissions thresholds, certain aspects of the proposed highway OBD
requirements carry with them serious concerns given the range of use
for heavy-duty highway trucks (line-haul trucks versus garbage trucks
versus urban delivery trucks, etc.). As discussed in various places in
section II of this preamble, this broad range of uses makes it
difficult for manufacturers to design a single approach that would, for
example, ensure frequent monitoring events on all possible
applications. This difficulty could be even more pronounced in the
nonroad industry given the greater number of possible applications.
[[Page 3207]]
We request comment regarding what any potential nonroad OBD
monitoring requirements should look like. More specifically, we request
comment regarding the inclusion of emissions thresholds versus relying
solely on comprehensive component monitoring. From commenters in favor
of emissions thresholds, we request details regarding the appropriate
level of emissions thresholds including data and strong engineering
analyses for/against the suggested level. We request comment regarding
the comprehensiveness of monitoring (i.e., the entire emissions control
system, aftertreatement devices only, feedback control systems only,
etc.).
3. What Should the OBD Standardization Features Be?
Should nonroad OBD include a requirement for a dedicated, OBD-only
malfunction indicator light? Should nonroad OBD require specific
communication protocols for communication of onboard information to
offboard devices and scan tools? What should those protocols be? What
are the needs of the nonroad service industry with respect to
standardization of onboard to offboard communications?
4. What Are the Prospects and/or Desires for International
Harmonization of Nonroad OBD?
Nonroad equipment is perhaps the most international of all mobile
source equipment. Land based nonroad equipment, while not as much so as
marine equipment, tends to be designed, produced, marketed, and sold to
a world market to a greater extent than is highway equipment. Given
that, is there a sense within the nonroad industry that international
harmonization is important? Imperative? Is the proper avenue for
putting into place nonroad OBD regulations the WWH-OBD process
discussed above? If so, is industry prepared to play a role in
developing a nonroad OBD element to the WWH-OBD document? Are other
government representatives prepared to do so?
II. What Are the Proposed OBD Requirements and When Would They Be
Implemented?
The following subsections describe our proposed OBD monitoring
requirements and the timelines for their implementation. The
requirements are indicative of our goal for the program which is a set
of OBD monitors that provide robust diagnosis of the emission control
system. Our intention is to provide industry sufficient time and
experience with satisfying the demands of the proposed OBD program.
While their engines already incorporate OBD systems, those systems are
generally less comprehensive and do not monitor the emission control
system in the ways we are proposing. Additionally, the proposed OBD
requirements represent a new set of technological requirements and a
new set of certification requirements for the industry in addition to
the 2007HD highway program and its challenging emission standards for
PM and NOX and other pollutants. As a result, we believe the
monitoring requirements and timelines outlined in this section
appropriately weigh the need for OBD monitors on the emission control
system and the need to gain experience with not only those monitors but
also the newly or recently added emission control hardware.
We request comment on all aspects of the requirements laid out in
this section and throughout this preamble. As discussed in Section IX,
we are also interested in comments concerning state run HDOBD-based
inspection and maintenance (I/M) programs, the level of interest in
such programs, and comments concerning the suitability of today's
proposed OBD requirements toward facilitating potential HDOBD I/M
programs in the future.
A. General OBD System Requirements
1. The OBD System
We are proposing that the OBD system be designed to operate for the
actual life of the engine in which it is installed. Further, the OBD
system cannot be programmed or otherwise designed to deactivate based
on age and/or mileage of the vehicle during the actual life of the
engine. This requirement is not intended to alter existing law and
enforcement practice regarding a manufacturer's liability for an engine
beyond its regulatory useful life, except where an engine has been
programmed or otherwise designed so that an OBD system deactivates
based on age and/or mileage of the engine.
We are also proposing that computer coded engine operating
parameters not be changeable without the use of specialized tools and
procedures (e.g. soldered or potted computer components or sealed (or
soldered) computer enclosures). Upon Administrator approval, certain
product lines may be exempted from this requirement if those product
lines can be shown to not need such protections. In making the approval
decision, the Administrator will consider such things as the current
availability of performance chips, performance capability of the
engine, and sales volume.
2. Malfunction Indicator Light (MIL) and Diagnostic Trouble Codes (DTC)
Upon detecting a malfunction within the emission control system,\5\
the OBD system must make some indication to the driver so that the
driver can take action to get the problem repaired. The proposal would
require that a dashboard malfunction indicator light (MIL) be
illuminated to inform the driver that a problem exists that needs
attention. Upon illumination of the MIL, the proposal would require
that a diagnostic trouble code (DTC) be stored in the engine's computer
that identifies the detected malfunction. This DTC would then be read
by a service technician to assist in making the necessary repair.
---------------------------------------------------------------------------
\5\ What constitutes a ``malfunction'' for over 14,000 pound
applications under today's proposal is covered in section II.B for
diesel engines, section II.C for gasoline engines, and section II.D
for all engines.
---------------------------------------------------------------------------
Because the MIL is meant to inform the driver of a detected
malfunction, we are proposing that the MIL be located on the driver's
side instrument panel and be of sufficient illumination and location to
be readily visible under all lighting conditions. We are proposing that
the MIL be amber (yellow) in color when illuminated because yellow is
synonymous with the notion of a ``cautionary warning''; the use of red
for the MIL would be strictly prohibited because red signifies
``danger'' which is not the proper message for malfunctions detected
according to today's proposal. Further, we are proposing that, when
illuminated, the MIL display the International Standards Organization
(ISO) engine symbol because this symbol has become accepted after 10
years of light-duty OBD as a communicator of engine and emissions
system related problems. We are also proposing that there be only one
MIL used to indicate all malfunctions detected by the OBD system on a
single vehicle. We believe this is important to avoid confusion over
multiple lights and, potentially, multiple interpretations of those
lights. Nonetheless, we seek comment on this limitation to one
dedicated MIL to communicate emissions-related malfunctions. We also
seek comment on the requirement that the MIL be amber in color since
some trucks may use liquid crystal display (LCD) panels to display
dashboard information and some such panels are monochromic and unable
to display color.
We are also interested in comments regarding the malfunction
indicator light and the symbol displayed to
[[Page 3208]]
communicate that there is an engine and/or emission-related
malfunction. As noted, we are proposing use of the ISO engine symbol as
shown in Table II.A-1. The U.S. Department of Transportation has
proposed use of an alternative ISO symbol to denote, specifically, an
emission-related malfunction. (68 FR 55217) That symbol is also shown
in Table II.A-1. While we are not proposing that this alternative
symbol be used, comments are solicited regarding whether this
alternative symbol provides a clearer message to the driver.
Generally, a manufacturer would be allowed sufficient time to be
certain that a malfunction truly exists before illuminating the MIL. No
one benefits if the MIL illuminates spuriously when a real malfunction
does not exist. Thus, for most OBD monitoring strategies, manufacturers
would not be required to illuminate the MIL until a malfunction clearly
exists which will be considered to be the case when the same problem
has occurred on two sequential driving cycles.\6\
---------------------------------------------------------------------------
\6\ Generally, a ``driving cycle'' or ``drive cycle'' consists
of engine startup and engine shutoff or consists of four hours of
continuous engine operation.
[GRAPHIC] [TIFF OMITTED] TP24JA07.000
To keep this clear in the onboard computer, we are proposing that
the OBD system make certain distinctions between the problems it has
detected, and that the system maintain a strict logic for diagnostic
trouble code (DTC) storage/erasure and for MIL illumination/
extinguishment. Whenever the enable criteria for a given monitor are
met, we would expect that monitor to run. For continuous monitors, this
would be during essentially all engine operation.\7\ For non-continuous
monitors, it would be during only a subset of engine operation.\8\ In
general, we are proposing that monitors make a diagnostic decision just
once per drive cycle that contains operation satisfying the enable
criteria for the given monitor.
---------------------------------------------------------------------------
\7\ A ``continuous'' monitor--if used in the context of
monitoring conditions for circuit continuity, lack of circuit
continuity, circuit faults, and out-of-range values--means sampling
at a rate no less than two samples per second. If a computer input
component is sampled less frequently for engine control purposes,
the signal of the component may instead be evaluated each time
sampling occurs.
\8\ A ``non-continuous'' monitor being a monitor that runs only
when a limited set of operating conditions occurs.
---------------------------------------------------------------------------
When a problem is first detected, we are proposing that a
``pending'' DTC be stored. If, during the subsequent drive cycle that
contains operation satisfying the enable criteria for the given
monitor, a problem in the components/system is not again detected, the
OBD system would declare that a malfunction does not exist and would,
therefore, erase the pending DTC. However, if, during the subsequent
drive cycle that contains operation satisfying the enable criteria for
the given monitor, a problem in the component/system is again detected,
a malfunction has been confirmed and, hence, a ``confirmed'' or ``MIL-
on'' DTC would be stored.\9\ Section II.F presents the requirements for
standardization of OBD information and communications. Upon storage of
a MIL-on DTC and, depending on the communication protocol used--ISO
15765-4 or SAE J1939--the pending DTC would either remain stored or be
erased, respectively. Today's proposal neither stipulates which
communication protocol nor which pending DTC logic be used. We are
proposing to allow the use of either of the existing protocols as is
discussed in more detail in section II.F. Upon storage of the MIL-on
DTC, the MIL must be illuminated.\10\ Also at this time, a
``permanent'' DTC would be stored (see section II.F.4 for more details
regarding permanent DTCs and our rationale for proposing them).\11\
---------------------------------------------------------------------------
\9\ Different industry standards organizations--the Society of
Automotive Engineers (SAE) and the International Standards
Organization (ISO)--use different terminology to refer to a ``MIL-
on'' DTC. For clarity, we use the term ``MIL-on'' DTC throughout
this preamble to convey the concept and not any requirement that
standard making bodies use the term in their standards.
\10\ Throughout this proposal, we refer to MIL illumination to
mean a steady, continuous illumination during engine operation
unless stated otherwise. This contrasts with the MIL illumination
logic used by many engine manufacturers today by which the MIL would
illuminate upon detection of a malfunction but would remain
illuminated only while the malfunction was actually occurring. Under
this latter logic, an intermittent malfunction or one that occurs
under only limited operating conditions may result in a MIL that
illuminates, extinguishes, illuminates, etc., as operating
conditions change.
\11\ A permanent DTC must be stored in a manner such that
electrical disconnections do not result in their erasure (i.e., they
must be stored in non-volatile random access memory (NVRAM)).
---------------------------------------------------------------------------
We are also proposing that, after three subsequent drive cycles
that contain operation satisfying the enable criteria for the given
monitor without any recurrence of the previously detected malfunction,
the MIL should be extinguished (unless there are other MIL-on DTCs
stored for which the MIL must also be illuminated), the permanent DTC
should be erased, but a ``previous-MIL-on'' DTC should remain
stored.\12\ We are proposing that the previous MIL-on DTC remain stored
for 40 engine warmup cycles after which time, provided the identified
malfunction has not been detected again and the MIL is presently not
illuminated for that malfunction, the previous-MIL-on DTC can be
erased.\13\ However, if an illuminated MIL is not extinguished, or if a
MIL-on DTC is not erased, by the OBD system itself but is instead
erased via scan tool or battery disconnect (which would erase all non-
permanent, volatile memory), the permanent DTC must remain stored. This
way, permanent DTCs can only be erased by the OBD system itself and
cannot be erased through human interaction with the system.
---------------------------------------------------------------------------
\12\ This general ``three trip'' condition for extinguishing the
MIL is true for all but two diesel systems/monitors--the misfire
monitor and the SCR system--and three gasoline systems/monitors--the
fuel system, the misfire monitor, and the evaporative system--which
have further conditions on extinguishing the MIL This is discussed
in more detail in sections II.B and II.C.
\13\ For simplicity, the discussion here refers to ``previous-
MIL-on'' DTCs only. The ISO 15765 standard and the SAE J1939
standard use different terms to refer to the concept of a previous-
MIL-on DTC. Our intent is to present the concept of our proposal in
this preamble and not to specify the terminology used by these
standard making bodies.
---------------------------------------------------------------------------
We are proposing that the manufacturer be allowed, upon
[[Page 3209]]
Administrator approval, to use alternative statistical MIL illumination
and DTC storage protocols to those described above (i.e., alternatives
to the ``first trip--pending DTC, second strip--MIL-on DTC logic). The
Administrator would consider whether the manufacturer provided data
and/or engineering evaluation adequately demonstrates that the
alternative protocols can evaluate system performance and detect
malfunctions in a manner that is equally effective and timely.
Alternative strategies requiring, on average, more than six driving
cycles for MIL illumination would probably not be accepted.
Upon storage of either a pending DTC and/or a MIL-on DTC, we are
proposing that the computer store a set of ``freeze frame'' data. This
freeze frame data would provide a snap shot of engine operating
conditions present at the time the malfunction occurred and was
detected. This information serves the repair technician in diagnosing
the problem and conducting the proper repair. The freeze frame data
should be stored upon storage of a pending DTC. If the pending DTC
matures to a MIL-on DTC, the manufacturer can choose to update the
freeze frame data or retain the freeze frame stored in conjunction with
the pending DTC. Likewise, any freeze frame stored in conjunction with
any pending or MIL-on DTC should be erased upon erasure of the DTC.
Further information concerning the freeze frame requirement and the
data required in the freeze frame is presented in section II.F.4,
below.
We are also proposing that the OBD system illuminate the MIL and
store a MIL-on DTC to inform the vehicle operator whenever the engine
enters a mode of operation that can affect the performance of the OBD
system. If such a mode of operation is recoverable (i.e., operation
automatically returns to normal at the beginning of the following
ignition cycle \14\), then in lieu of illuminating the MIL when the
mode of operation is entered, the OBD system may wait to illuminate the
MIL and store the MIL-on DTC if the mode of operation is again entered
before the end of the next ignition cycle. We are proposing this
because many operating strategies are designed such that they continue
automatically through to the next key-off. Regardless, upon the next
key-on, the engine control would start off in ``normal'' operating mode
and would return to the ``abnormal'' operating mode only if the
condition causing the abnormal mode was again encountered. In such
cases, we are proposing to allow that the MIL be illuminated during the
second consecutive drive cycle during which such an ``abnormal'' mode
is engaged.\15\
---------------------------------------------------------------------------
\14\ ``Ignition Cycle'' means a drive cycle that begins with
engine start and includes an engine speed that exceeds 50 to 150
rotations per minute (rpm) below the normal, warmed-up idle speed
(as determined in the drive position for vehicles equipped with an
automatic transmission) for at least two seconds plus or minus one
second.
\15\ Note that we use the term ``abnormal'' to refer to an
operating mode that the engine is designed to enter upon determining
that ``normal'' operation cannot be maintained. Therefore, the term
``abnormal'' is somewhat of a misnomer since the engine is doing
what it has been designed to do. Nonetheless, the abnormal operating
mode is clearly not the operating mode the manufacturer has intended
for optimal operation. Such operating modes are sometimes referred
to as ``default'' operating modes or ``limp-home'' operating modes.
---------------------------------------------------------------------------
Whether or not the ``abnormal'' mode of operation is recoverable,
in this context, has nothing to do with whether the detected
malfunction goes away or stays. Instead, it depends solely on whether
or not the engine, by design, will stay in abnormal operating mode on
the next key-on. We are proposing this MIL logic because often the
diagnostic (i.e., monitor) that caused the engine to enter abnormal
mode cannot run again once the engine is in the abnormal mode. So, if
the MIL logic associated with abnormal mode activation was always a
two-trip diagnostic, abnormal mode activation would set a pending DTC
on the first trip and, since the system would then be stuck in that
abnormal operating mode and would never be able to run the diagnostic
again, the pending DTC could never mature to a MIL-on DTC nor
illuminate the MIL. Hence, the MIL must illuminate upon the first entry
into such an abnormal operating mode. If such a mode is recoverable,
the engine will start at the next key-on in ``normal'' mode allowing
the monitor to run again and, assuming another detection of the
condition, the system would set a MIL-on DTC and illuminate the MIL.
The OBD system would not need to store a DTC nor illuminate the MIL
upon abnormal mode operation if other telltale conditions would result
in immediate action by the driver. Such telltale conditions would be,
for example, an overt indication like a red engine shut-down warning
light. The OBD system also need not store a DTC nor illuminate the MIL
upon abnormal mode operation if the mode is indeed an auxiliary
emission control device (AECD) approved by the Administrator.
There may be malfunctions of the MIL itself that would prevent it
from illuminating. A repair technician--or possibly an I/M inspector--
would still be able to determine the status of the MIL (i.e., commanded
``on'' or ``off'') by reading electronic information available through
a scan tool, but there would be no indication to the driver of an
emissions-related malfunction should one occur. Unidentified
malfunctions may cause excess emissions to be emitted from the vehicle
and may even cause subsequent deterioration or failure of other
components or systems without the driver's knowledge. In order to
prevent this, the manufacturer must ensure that the MIL is functioning
properly. For this reason, we are proposing two requirements to check
the functionality of the MIL itself. First, the MIL would be required
to illuminate for a minimum of five seconds when the vehicle is in the
key-on, engine-off position. This allows an interested party to check
the MIL's functionality simply by turning the key to the key-on
position. While the MIL would be physically illuminated during this
functional check, the data stream value for the MIL command status
would be required to indicate ``off'' during this check unless, of
course, the MIL was currently being commanded ``on'' for a detected
malfunction. This functional check of the MIL would not be required
during vehicle operation in the key-on, engine-off position subsequent
to the initial engine cranking of an ignition cycle (e.g., due to an
engine stall or other non-commanded engine shutoff).
The second functional check requirement we are proposing requires
the OBD system to perform a circuit continuity check of the electrical
circuit that is used to illuminate the MIL to verify that the circuit
is not shorted or open (e.g., a burned out bulb). While there would not
be an ability to illuminate the MIL when such a malfunction is
detected, the electronically readable MIL command status in the onboard
computer would be changed from commanded ``off'' to ``on''. This would
allow the truck owner or fleet maintenance staff to quickly determine
whether an extinguished MIL means ``no malfunctions'' or ``broken
MIL.'' It would also serve, should it become of interest in the future,
complete automation of the I/M process by eliminating the need for
inspectors to input manually the results of their visual inspections.
Feedback from passenger car I/M programs indicates that the current
visual bulb check performed by inspectors is subject to error and
results in numerous vehicles being falsely failed or passed. By
requiring monitoring of the circuit itself, the entire pass/fail
criteria of an I/M program could be determined by the electronic
information available through a scan tool, thus better facilitating
quick
[[Page 3210]]
and effective inspections and minimizing the chance for manually-
entered errors.
At the manufacturer's option, the MIL may be used to indicate
readiness status in a standardized format (see Section II.F) in the
key-on, engine-off position. Readiness status is a term used in light-
duty OBD that refers to a vehicle's readiness for I/M inspection. For a
subset of monitors--those that are non-continuous monitors for which an
emissions threshold exists (see sections II.B and II.C for more on
emissions thresholds)--a readiness status indicator must be stored in
memory to indicate whether or not that particular monitor has run
enough times to make a diagnostic decision. Until the monitor has run
sufficient times, the readiness status would indicate ``not ready''.
Upon running sufficient times, the readiness status would indicate
``ready.'' This serves to protect against drivers disconnecting their
battery just prior to the I/M inspection so as to erase any MIL-on
DTCs. Such an action would simultaneously set all readiness status
indicators to ``not ready'' resulting in a notice to return to the
inspection site at a future date. Readiness indicators also help repair
technicians because, after completing a repair, they can operate the
vehicle until the readiness status indicates ``ready'' and, provided no
DTCs are stored, know that the repair has been successful. We are
proposing that HDOBD systems follow this same readiness status logic as
used for years in light-duty OBD both to assist repair technicians and
to facilitate potential future HDOBD I/M programs.
We are also proposing that the manufacturer, upon Administrator
approval, be allowed to use the MIL to indicate which, if any, DTCs are
currently stored (e.g., to ``blink'' the stored codes). The
Administrator would approve the request if the manufacturer can
demonstrate that the method used to indicate the DTCs will not be
unintentionally activated during any inspection test or during routine
driver operation.
3. Monitoring Conditions
a. Background
Given that the intent of the proposed OBD requirements is to
monitor the emission control system for proper operation, it is logical
that the OBD monitors be designed such that they monitor the emission
control system during typical driving conditions. While many OBD
monitors would be designed such that they are continuously making
decisions about the operational status of the engine, many--and
arguably the most critical--monitors are not so designed. For example,
an OBD monitor whose function is to monitor the active fuel injection
system of a NOX adsorber or a DPF cannot be continuously
monitoring that function since that function occurs on an infrequent
basis. This OBD monitor presumably would be expected to ``run,'' or
evaluate the active injection system, during an actual fuel injection
event.
For this reason, manufacturers are allowed to determine the most
appropriate times to run their non-continuous OBD monitors. This way,
they are able to make an OBD evaluation either at the operating
condition when an emission control system is active and its operational
status can best be evaluated, and/or at the operating condition when
the most accurate evaluation can be made (e.g., highly transient
conditions or extreme conditions can make evaluation difficult).
Importantly, manufacturers are prohibited from using a monitoring
strategy that is so restrictive such that it rarely or never runs. To
help protect against monitors that rarely run, we are proposing an
``in-use monitor performance ratio'' requirement which is detailed in
section II.E.
The set of operating conditions that must be met so that an OBD
monitor can run are called the ``enable criteria'' for that given
monitor. These enable criteria are often different for different
monitors and may well be different for different types of engines. A
large diesel engine intended for use in a Class 8 truck would be
expected to see long periods of relatively steady-state operation while
a smaller engine intended for use in an urban delivery truck would be
expected to see a lot of transient operation. Manufacturers will need
to balance between a rather loose set of enable criteria for their
engines and vehicles given the very broad range of operation HD highway
engines see and a tight set of enable criteria given the desire for
greater monitor accuracy.
b. General Monitoring Conditions
i. Monitoring Conditions for All Engines
As guidance to manufacturers, we are proposing the following
criteria to assist manufacturers in developing their OBD enable
criteria. These criteria would be used by the Agency during our OBD
certification approval process to ensure that monitors run on a
frequent basis during real world driving conditions. These criteria
would be:
The monitors should run during conditions that are
technically necessary to ensure robust detection of malfunctions (e.g.,
to avoid false passes and false indications of malfunctions);
The monitor enable criteria should ensure monitoring will
occur during normal vehicle operation; and,
Monitoring should occur during at least one test used by
EPA for emissions verification `` either the HD Federal Test Procedure
(FTP) transient cycle, or the Supplementary Emissions Test (SET).\16\
---------------------------------------------------------------------------
\16\ See 40 CFR part 86, subpart N for details of EPA's test
procedures.
---------------------------------------------------------------------------
As discussed in more detail in sections II.B through II.D, we are
proposing that manufacturers define the monitoring conditions, subject
to Administrator approval, for detecting the malfunctions required by
this proposal. The Administrator would determine if the monitoring
conditions proposed by the manufacturer for each monitor abide by the
above criteria.
In general, except as noted in sections II.B through II.D, the
proposed regulation would require each monitor to run at least once per
driving cycle in which the applicable monitoring conditions are met.
The proposal would also require certain monitors to run continuously
throughout the driving cycle. These include a few threshold monitors
(e.g., fuel system monitor) and most circuit continuity monitors. While
a basic definition of a driving cycle (e.g., from ignition key-on and
engine startup to engine shutoff) has been sufficient for passenger
cars, the driving habits of many types of vehicles in the heavy-duty
industry dictate an alternate definition. Specifically, many heavy-duty
operators will start the engine and leave it running for an entire day
or, in some cases, even longer. As such, we are proposing that any
period of continuous engine-on operation of four hours be considered a
complete driving cycle. A new driving cycle would begin following such
a four hour period, regardless of whether or not the engine had been
shut down. Thus, the ``clock'' for monitors that are required to run
once per driving cycle would be reset to run again (in the same key-on
engine start or trip) once the engine has been operated beyond four
hours continuously. This would avoid an unnecessary delay in detection
of malfunctions simply because the heavy-duty vehicle operator has
elected to leave the vehicle running continuously for an entire day or
days at a time.
Manufacturers may request Administrator approval to define
monitoring conditions that are not encountered during the FTP cycle. In
evaluating the manufacturer's request, the Administrator will consider
the degree to which the requirement to run
[[Page 3211]]
during the FTP cycle restricts in-use monitoring, the technical
necessity for defining monitoring conditions that are not encountered
during the FTP cycle, data and/or an engineering evaluation submitted
by the manufacturer which demonstrate that the component/system does
not normally function, or monitoring is otherwise not feasible, during
the FTP cycle, and, where applicable, the ability of the manufacturer
to demonstrate that the monitoring conditions will satisfy the minimum
acceptable in-use monitor performance ratio requirement as defined
below.
ii. In-Use Performance Tracking Monitoring Conditions
In addition to the general monitoring conditions above, we are
proposing that manufacturers be required to implement software
algorithms in the OBD system to individually track and report in-use
performance of the following monitors in the standardized format
specified in section II.E:
Diesel NMHC converting catalyst(s)
Diesel NOX converting catalyst(s)
Gasoline catalyst(s)
Exhaust gas sensor(s)
Gasoline evaporative system
Exhaust gas recirculation (EGR) system
Variable valve timing (VVT) system
Gasoline secondary air system
Diesel particulate filter system
Diesel boost pressure control system
Diesel NOX adsorber(s)
The OBD system is not required to track and report in-use
performance for monitors other than those specifically identified
above.
iii. In-Use Performance Ratio Requirement
We are also proposing that, for all 2013 and subsequent model year
engines, manufacturers be required to define monitoring conditions
that, in addition to meeting the general monitoring conditions, ensure
that certain monitors yield an in-use performance ratio (which monitors
and the details that define the performance ratio are defined in
section II.E) that meets or exceeds the minimum acceptable in-use
monitor performance ratio for in-use vehicles. We are proposing a
minimum acceptable in-use monitor performance ratio of 0.100 for all
monitors specifically required to track in-use performance. This means
that the monitors listed in section II.A.3.ii above must run and make
valid diagnostic decisions during 10 percent of the vehicle's trips. We
intend to work with industry during the initial years of implementation
to gather data on in-use performance ratios and may revise this ratio
lower as appropriate depending on what we learn.
Note that manufacturers may not use the calculated ratio (or any
element thereof), or any other indication of monitor frequency, as a
monitoring condition for a monitor. For example, the manufacturer would
not be allowed to use a low ratio to enable more frequent monitoring
through diagnostic executive priority or modification of other
monitoring conditions, or to use a high ratio to enable less frequent
monitoring.
4. Determining the Proper OBD Malfunction Criteria
For determining the malfunction criteria for diesel engine monitors
associated with an emissions threshold (see sections II.B and II.C for
more on emissions thresholds), we are proposing that manufacturers be
required to determine the appropriate emissions test cycle such that
the most stringent monitor would result. In general, we believe that
manufacturers can make this determination based on engineering
judgement, but there may be situations where testing would be required
to make the determination. We do not necessarily anticipate challenging
a manufacturer's determination of which test cycle to use. Nonetheless,
the manufacturer should be prepared, perhaps with test data, to justify
their determination.
We are also proposing that, for engines equipped with emission
controls that experience infrequent regeneration events (e.g., a DPF
and/or a NOX adsorber), a manufacturer must adjust the
emission test results for monitors that are required to indicate a
malfunction before emissions exceed a certain emission threshold.\17\
For each such monitor, the manufacturer would have to adjust the
emission result as done in accordance with the provisions of section
86.004-28(i) with the component for which the malfunction criteria are
being established having been deteriorated to the malfunction
threshold. As proposed, the adjusted emission value must be used for
purposes of determining whether or not the applicable emission
threshold is exceeded.
---------------------------------------------------------------------------
\17\ See proposed Sec. 86.010-18(f).
---------------------------------------------------------------------------
While we believe that this adjustment process for monitors of
systems that experience infrequent regeneration events makes sense and
would result in robust monitors, we also believe that it could prove to
be overly burdensome for manufacturers. For example, a NOX
adsorber threshold being evaluated by running an FTP using a
``threshold'' part (i.e., a NOX adsorber deteriorated such
that tailpipe emissions are at the applicable thresholds) may be
considered acceptable provided the NOX adsorber does not
regenerate during the test, but it may be considered unacceptable if
the NOX adsorber does happen to regenerate during the test.
This could happen because emissions would be expected to increase
slightly during the regeneration event thereby causing emissions to be
slightly above the applicable threshold. This would require the
manufacturer to recalibrate the NOX adsorber monitor to
detect at a lower level of deterioration to ensure that a regeneration
event would not cause an exceedance of the threshold during an
emissions test. After such a recalibration, the emissions occurring
during the regeneration event would be lower than before because the
new ``threshold'' NOX adsorber would have a slightly higher
conversion efficiency. We are concerned that manufacturers may find
themselves in a difficult iterative process calibrating such monitors
that, in the end, will not be correspondingly more effective.
For this reason, we request comment regarding the burden associated
with the need to consider regeneration events in determining compliance
with emissions thresholds. We also request comment on how to address
any environmental concern versus the burden. Would it perhaps be best
to simply use the emissions adjustments that are determined in
accordance with section 86.004-28(i)? Is it necessary to even consider
regeneration emissions when determining emission threshold compliance
or is it perhaps best to ignore regeneration events in determining
threshold calibrations?
B. Monitoring Requirements and Timelines for Diesel-Fueled/Compression-
Ignition Engines
Table II.B-1 summarizes the proposed diesel fueled compression
ignition emissions thresholds at which point a component or system has
failed to the point of requiring an illuminated MIL and a stored DTC.
More detail regarding the specific monitoring requirements,
implementation schedules, and liabilities can be found in the sections
that follow.
[[Page 3212]]
Table II.B-1.--Proposed Emissions Thresholds for Diesel Fueled CI Engines over 14,000 Pounds
----------------------------------------------------------------------------------------------------------------
Component/monitor MY NMHC CO NOX PM
----------------------------------------------------------------------------------------------------------------
NMHC catalyst system...................................... 2010-2012 2.5x ....... ....... ...........
2013+ 2x ....... ....... ...........
NOX catalyst system....................................... 2010+ ....... ....... +0.3 ...........
DPF system................................................ 2010-2012 2.5x ....... ....... 0.05/+0.04
2013+ 2x ....... ....... 0.05/+0.04
Air-fuel ratio sensors upstream........................... 2010-2012 2.5x 2.5x +0.3 0.03/+0.02
2013+ 2x 2x +0.3 0.03/+0.02
Air-fuel ratio sensors downstream......................... 2010-2012 2.5x ....... +0.3 0.05/+0.04
2013+ 2x ....... +0.3 0.05/+0.04
NOX sensors............................................... 2010+ ....... ....... +0.3 0.05/+0.04
``Other monitors'' with emissions thresholds (see section 2010-2012 2.5x 2.5x +0.3 0.03/+0.02
II.B)....................................................
2013+ 2x 2x +0.3 0.03/+0.02
----------------------------------------------------------------------------------------------------------------
Notes: MY=Model Year; 2.5x means a multiple of 2.5 times the applicable emissions standard or family emissions
limit (FEL); +0.3 means the standard or FEL plus 0.3; 0.05/+0.04 means an absolute level of 0.05 or an
additive level of the standard or FEL plus 0.04, whichever level is higher; not all proposed monitors have
emissions thresholds but instead rely on functionality and rationality checks as described in section II.D.4.
There are exceptions to the emissions thresholds shown in Table
II.B-1 whereby a manufacturer can demonstrate that emissions do not
exceed the threshold even when the component or system is non-
functional at which point a functional check would be allowed.
Note that, in general, the monitoring strategies designed to meet
the requirements discussed below should not involve the alteration of
the engine control system or the emissions control system such that
tailpipe emissions would increase. We do not want emissions to
increase, even for short durations, for the sole purpose of monitoring
the systems intended to control emissions. The Administrator would
consider such monitoring strategies on a case-by-case basis taking into
consideration the emissions impact and duration of the monitoring
event. However, much effort has been expended in recent years to
minimize engine operation that results in increased emissions and we
encourage manufacturers to develop monitoring strategies that do not
require alteration of the basic control system.
1. Fuel System Monitoring
a. Background
The fuel system of a diesel engine is an essential component of the
engine's emissions control system. Proper delivery of fuel--quantity,
pressure, and timing--can play a crucial role in maintaining low
engine-out emissions. The performance of the fuel system is also
critical for aftertreatment device control strategies. As such,
thorough monitoring of the fuel system is an essential element in an
OBD system. The fuel system is primarily comprised of a fuel pump, fuel
pressure control device, and fuel injectors. Additionally, the fuel
system generally has sophisticated control strategies that utilize one
or more feedback sensors to ensure the proper amount of fuel is being
delivered to the cylinders. While gasoline engines have undergone
relatively minor hardware changes (but substantial fine-tuning in the
control strategy and feedback inputs), diesel engines have more
recently undergone substantial changes to the fuel system hardware and
now incorporate more refined control strategies and feedback inputs.
For diesel engines, a substantial change has occurred in recent
years as manufacturers have transitioned to new high-pressure fuel
systems. One of the most widely used is a high-pressure common-rail
fuel injection system, which is generally comprised of a high-pressure
fuel pump, a fuel rail pressure sensor, a common fuel rail that feeds
all injectors, individual fuel injectors that directly control fuel
injection quantity and timing for each cylinder, and a closed-loop
feedback system that uses the fuel rail pressure sensor to achieve the
commanded fuel rail pressure. Unlike older style fuel systems where
fuel pressure was mechanically linked to engine speed (and thus, varied
from low to high as engine speed increased), common-rail systems are
capable of controlling fuel pressure independent of engine speed. This
increase in fuel pressure control allows greater flexibility in
optimizing the performance and emission characteristics of the engine.
The ability of the system to generate high pressure independent of
engine speed also improves fuel delivery at low engine speeds.
Precise control of the fuel injection timing is crucial for optimal
engine and emission performance. As injection timing is advanced (i.e.,
fuel injection occurs earlier), hydrocarbon (HC) emissions and fuel
consumption are decreased but oxides of nitrogen (NOX)
emissions are increased. As injection timing is retarded (i.e., fuel
injection occurs later), NOX emissions can be reduced but HC
emissions, particulate matter (PM) emissions, and fuel consumption
increase. Most modern diesel fuel systems even provide engine
manufacturers with the ability to separate a single fuel injection
event into discrete events such as pilot (or pre) injection, main
injection, and post injection.
Given the important role that modern diesel fuel systems play in
emissions control, malfunctions or deterioration that would affect the
fuel pressure control, injection timing, pilot/main/post injection
timing or quantity, or ability to accurately perform rate-shaping could
lead to substantial increases in emissions (primarily NOX or
PM), often times with an associated change in fuel consumption.
b. Fuel System Monitoring Requirements
We are proposing that the OBD system monitor the fuel delivery
system to verify that it is functioning properly. The fuel system
monitor would be required to monitor for malfunctions in the injection
pressure control, injection quantity, injection timing, and feedback
control (if equipped). The individual electronic components (e.g.,
actuators, valves, sensors, pumps) that are used in the fuel system and
not specifically addressed in this section shall be monitored in
accordance with the comprehensive component requirements in section
II.D.4.
i. Fuel System Pressure Control
We are proposing that the OBD system continuously monitor the fuel
system's ability to control to the desired fuel pressure. The OBD
system would have to detect a malfunction of the fuel system's pressure
control system when
[[Page 3213]]
the pressure control system is unable to maintain an engine's emissions
at or below the emissions thresholds for ``other monitors'' as shown in
Table II.B-1. For engines in which no failure or deterioration of the
fuel system pressure control could result in an engine's emissions
exceeding the applicable emissions thresholds, the OBD system would be
required to detect a malfunction when the system has reached its
control limits such that the commanded fuel system pressure cannot be
delivered.
ii. Fuel System Injection Quantity
We are proposing that the OBD system detect a malfunction of the
fuel injection system when the system is unable to deliver the
commanded quantity of fuel necessary to maintain an engine's emissions
at or below the emissions thresholds for ``other monitors'' as shown in
Table II.B-1. For engines in which no failure or deterioration of the
fuel injection quantity could result in an engine's emissions exceeding
the applicable emissions thresholds, the OBD system would be required
to detect a malfunction when the system has reached its control limits
such that the commanded fuel quantity cannot be delivered.
iii. Fuel System Injection Timing
We are proposing that the OBD system detect a malfunction of the
fuel injection system when the system is unable to deliver fuel at the
proper crank angle/timing (e.g., injection timing too advanced or too
retarded) necessary to maintain an engine's emissions at or below the
emissions thresholds for ``other monitors'' as shown in Table II.B-1.
For engines in which no failure or deterioration of the fuel injection
timing could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system would be required to detect a
malfunction when the system has reached its control limits such that
the commanded fuel injection timing cannot be achieved.
iv. Fuel System Feedback Control
If the engine is equipped with feedback control of the fuel system
(e.g., feedback control of pressure or pilot injection quantity), we
are proposing that the OBD system detect a malfunction when and if:
The system fails to begin feedback control within a
manufacturer specified time interval;
A failure or deterioration causes open loop or default
operation; or
Feedback control has used up all of the adjustment allowed
by the manufacturer.
A manufacturer may temporarily disable monitoring for malfunctions
where the feedback control has used up all of the adjustment allowed by
the manufacturer during conditions that the monitor cannot distinguish
robustly between a malfunctioning system and a properly operating
system. To do so, the manufacturer would be required to submit data
and/or engineering analyses demonstrating that the control system, when
operating as designed on an engine with all emission controls working
properly, routinely operates during these conditions with all of the
adjustment allowed by the manufacturer used up. In lieu of detecting,
with a fuel system specific monitor, when the system fails to begin
feedback control within a manufacturer specified time interval and/or
when a failure or deterioration causes open loop or default operation,
the OBD system may monitor the individual parameters or components that
are used as inputs for fuel system feedback control provided that the
monitors detect all malfunctions related to feedback control.
c. Fuel System Monitoring Conditions
The OBD system would be required to monitor continuously for
malfunctions of the fuel pressure control and feedback control.
Manufacturers would be required to define the monitoring conditions for
malfunctions of the injection quantity and injection timing such that
the minimum performance ratio requirements discussed in section II.E
would be met.
d. Fuel System MIL Illumination and DTC Storage
We are proposing the general MIL illumination and DTC storage
requirements as discussed in section II.A.2.
2. Engine Misfire Monitoring
a. Background
Misfire, the lack of combustion in the cylinder, causes increased
engine-out hydrocarbon emissions. On gasoline engines, misfire results
from the absence of spark, poor fuel metering, and poor compression.
Further, misfire can be intermittent on gasoline engines (e.g., the
misfire only occurs under certain engine speeds or loads).
Consequently, our existing under 14,000 pound OBD regulation requires
continuous monitoring for misfire malfunctions on gasoline engines.
In contrast, manufacturers have historically maintained that a
diesel engine with traditional diesel technology misfires only due to
poor compression (e.g., worn valves or piston rings, improper injector
or glow plug seating). They have also maintained that, when poor
compression results in a misfiring cylinder, the cylinder will misfire
under all operating conditions rather than only some operating
conditions. For that reason, our existing under 14,000 pound OBD
regulation has not required continuous monitoring for misfire
malfunctions on diesel engines.
However, with the increased use of EGR and its use to varying
degrees at different speeds and load, and with emerging technologies
such as homogeneous charge compression ignition (HCCI), we believe that
the conventional wisdom regarding diesel engines and misfires no longer
holds true. These newer technologies may indeed result in misfires that
are intermittent, spread out among various cylinders, and that only
happen at certain speeds and loads.
b. Misfire Monitoring Requirements
We are proposing that the OBD system monitor the engine for misfire
causing excess emissions. The OBD system must be capable of detecting
misfire occurring in one or more cylinders. To the extent possible
without adding hardware for this specific purpose, the OBD system must
also identify the specific misfiring cylinder. If more than one
cylinder is continuously misfiring, a separate DTC must be stored
indicating that multiple cylinders are misfiring. When identifying
multiple cylinder misfire, the OBD system is not required to also
identify each of the continuously misfiring cylinders individually
through separate DTCs.
For 2013 and subsequent model year engines, we are proposing a more
stringent requirement that the OBD system detect a misfire malfunction
causing emissions to exceed the emissions thresholds for ``other
monitors'' as shown in Table II.B-1. This requirement to detect engine
misfire prior to exceeding an emissions threshold would apply only to
those engines equipped with sensors capable of detecting combustion or
combustion quality (e.g., cylinder pressure sensors used in homogeneous
charge compression ignition (HCCI) control systems). Engines without
such sensors would have to detect only when one or more cylinders are
continually misfiring.
To determine what level of misfire would cause emissions to exceed
the applicable emissions thresholds, we are proposing that
manufacturers determine
[[Page 3214]]
the percentage of misfire evaluated in 1000 revolution increments that
would cause emissions from an emission durability demonstration engine
to exceed the emissions thresholds if the percentage of misfire were
present from the beginning of the test. To establish this percentage of
misfire, the manufacturer would utilize misfire events occurring at
equally spaced, complete engine cycle intervals, across randomly
selected cylinders throughout each 1000-revolution increment. If this
percentage of misfire is determined to be lower than one percent, the
manufacturer may set the malfunction criteria at one percent. Any
malfunction should be detected if the percentage of misfire established
via this testing is exceeded regardless of the pattern of misfire
events (e.g., random, equally spaced, continuous).
The manufacturer may employ other revolution increments besides the
1000 revolution increment being proposed. To do so, the manufacturer
would need to demonstrate that the strategy would be equally effective
and timely in detecting misfire.
c. Engine Misfire Monitoring Conditions
For engines without combustion sensors, we are proposing that the
OBD system monitor for misfire during engine idle conditions at least
once per drive cycle in which the monitoring conditions for misfire are
met. The manufacturer would be required to define monitoring
conditions, supported by manufacturer-submitted data and/or engineering
analyses, that demonstrate that the monitoring conditions: are
technically necessary to ensure robust detection of malfunctions (e.g.,
avoid false passes and false detection of malfunctions); require no
more than 1000 cumulative engine revolutions; and, do not require any
single continuous idle operation of more than 15 seconds to make a
determination that a malfunction is present (e.g., a decision can be
made with data gathered during several idle operations of 15 seconds or
less).
For 2013 and subsequent model year engines with combustion sensors,
we are proposing that the OBD system continuously monitor for misfire
under all positive torque engine speeds and load conditions. If a
monitoring system cannot detect all misfire patterns under all positive
torque engine speeds and load conditions, the manufacturer may request
that the Administrator approve the monitoring system nonetheless. In
evaluating the manufacturer's request, the Administrator would consider
the following factors: the magnitude of the region(s) in which misfire
detection is limited; the degree to which misfire detection is limited
in the region(s) (i.e., the probability of detection of misfire
events); the frequency with which said region(s) are expected to be
encountered in-use; the type of misfire patterns for which misfire
detection is troublesome; and demonstration that the monitoring
technology employed is not inherently incapable of detecting misfire
under required conditions (i.e., compliance can be achieved on other
engines). The evaluation would be based on the following misfire
patterns: equally spaced misfire occurring on randomly selected
cylinders; single cylinder continuous misfire; and, paired cylinder
(cylinders firing at the same crank angle) continuous misfire.
d. Engine Misfire MIL Illumination and DTC Storage
For engines without combustion sensors, we are proposing the
general MIL illumination and DTC storage requirements as discussed in
section II.A.2.
For 2013 and subsequent model year engines with combustion sensors,
we are proposing that, after four detections of the percentage of
misfire that would cause emissions to exceed the applicable emissions
thresholds during a single driving cycle, a pending DTC would be
stored. If a pending DTC is stored, the OBD system would be required to
illuminate the MIL and store a MIL--on DTC if the percentage of misfire
is again exceeded four times during either: the driving cycle
immediately following the storage of the pending DTC, regardless of the
conditions encountered during the driving cycle; or, the next driving
cycle in which similar conditions are encountered to the engine
conditions that occurred when the pending DTC was stored.\18\ For
erasure of the pending DTC, we are proposing if, by the end of the next
driving cycle in which similar conditions have been encountered to the
engine conditions that occurred when the pending DTC was stored without
an exceedance of the specified percentage of misfire, the pending DTC
may be erased. The pending DTC may also be erased if similar conditions
are not encountered during the next 80 driving cycles immediately
following initial detection of the malfunction.
---------------------------------------------------------------------------
\18\ ``Similar conditions,'' as used in conjunction with misfire
and fuel system monitoring, means engine conditions having an engine
speed within 375 rpm, load conditions within 20 percent, and the
same warm up status (i.e., cold or hot) as existing during the
applicable previous problem detection. The Administrator may approve
other definitions of similar conditions based on comparable
timeliness and reliability in detecting similar engine operation.
---------------------------------------------------------------------------
We are proposing some specific items with respect to freeze frame
storage associated with engine misfire. The OBD system shall store and
erase freeze frame conditions either in conjunction with storing and
erasing a pending DTC or in conjunction with storing a MIL--on DTC and
erasing a MIL--on DTC. In addition to those proposed requirements
discussed in section II.A.2, we are proposing that, if freeze frame
conditions are stored for a malfunction other than a misfire
malfunction when a DTC is stored, the previously stored freeze frame
information shall be replaced with freeze frame information regarding
the misfire malfunction (i.e., the misfire's freeze frame information
should take precedence over freeze frames for other malfunctions).
Further, we are proposing that, upon detection of misfire, the OBD
system store the following engine conditions: engine speed, load, and
warm up status of the first misfire event that resulted in the storage
of the pending DTC.
Lastly, we are proposing that the MIL may be extinguished after
three sequential driving cycles in which similar conditions have been
encountered without an exceedance of the specified percentage of
misfire.
3. Exhaust Gas Recirculation (EGR) System Monitoring
a. Background
Exhaust gas recirculation (EGR) systems are currently being used by
many heavy-duty engine manufacturers to meet the 2.5 g/bhp-hr
NOX+NMHC standard for 2004 and later model year engines. (65
FR 59896) EGR reduces NOX emissions in several ways. First,
the recirculated exhaust gases dilute the intake air--i.e., oxygen in
the fresh air is displaced with relatively non-reactive exhaust gases--
which, in turn, results in less oxygen to form NOX. Second,
EGR absorbs heat from the combustion process which reduces combustion
chamber temperatures which, in turn, reduces NOX formation.
The amount of heat absorbed from the combustion process is a function
of EGR flow rate and recirculated gas temperature, both of which are
controlled to minimize NOX emissions. An EGR cooler can be
added to the EGR system to lower the recirculated gas temperature which
further enhances NOX control. We fully expect that 2007 and
later model year engines will continue to make use of cooled EGR
systems.
While in theory the EGR system simply routes some exhaust gas back
to the intake, production systems can be complex and involve many
components to ensure accurate control of EGR flow
[[Page 3215]]
to maintain acceptable PM and NOX emissions while minimizing
effects on fuel economy. To control EGR flow rates, EGR systems
normally use the following components: an EGR valve, valve position
sensor, boost pressure sensor, intake temperature sensor, intake
(fresh) airflow sensor, and tubing or piping to connect the various
components of the system. EGR temperature sensors and exhaust
backpressure sensors can also be used. Additionally, some systems use a
variable geometry turbocharger to provide the backpressure necessary to
drive the EGR flow. Therefore, EGR is not a stand alone emission
control device. Rather, it is carefully integrated with the air
handling system (turbocharging and intake cooling) to control
NOX while not adversely affecting PM emissions and fuel
economy.
b. EGR System Monitoring Requirements
We are proposing that the OBD system monitor the EGR system on
engines so equipped for low EGR flow rate, high EGR flow rate, and slow
EGR flow response malfunctions. For engines so equipped, we are
proposing that the EGR feedback control be monitored. Also, for engines
equipped with EGR coolers (e.g., heat exchangers), the OBD system would
have to monitor the cooler for malfunctions associated with
insufficient EGR cooling. The individual electronic components (e.g.,
actuators, valves, sensors) that are used in the EGR system would be
monitored in accordance with the comprehensive component requirements
presented in section II.D.4.
i. EGR Low Flow Malfunctions
We are proposing that the OBD system detect a malfunction prior to
a decrease from the manufacturer's specified EGR flow rate that would
cause an engine's emissions to exceed the emissions thresholds for
``other monitors'' as shown in Table II.B-1. For engines in which no
failure or deterioration of the EGR system that causes a decrease in
flow could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system would have to detect a malfunction
when the system has reached its control limits such that it cannot
increase EGR flow to achieve the commanded flow rate.
ii. EGR High Flow Malfunctions
We are proposing that the OBD system detect a malfunction of the
EGR system, including a leaking EGR valve--i.e., exhaust gas flowing
through the valve when the valve is commanded closed--prior to an
increase from the manufacturer's specified EGR flow rate that would
cause an engine's emissions to exceed the emissions thresholds for
``other monitors'' as shown in Table II.B-1. For engines in which no
failure or deterioration of the EGR system that causes an increase in
flow could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system would have to detect a malfunction
when the system has reached its control limits such that it cannot
reduce EGR flow to achieve the commanded flow rate.
iii. EGR Slow Response Malfunctions
We are proposing that the OBD system detect a malfunction of the
EGR system prior to any failure or deterioration in the capability of
the EGR system to achieve the commanded flow rate within a
manufacturer-specified time that would cause an engine's emissions to
exceed the emissions thresholds for ``other monitors'' as shown in
Table II.B-1. The OBD system would have to monitor both the capability
of the EGR system to respond to a commanded increase in flow and the
capability of the EGR system to respond to a commanded decrease in
flow.
iv. EGR Feedback Control
We are proposing that the OBD system on any engine equipped with
feedback control of the EGR system (e.g., feedback control of flow,
valve position, pressure differential across the valve via intake
throttle or exhaust backpressure), detect a malfunction when and if:
The system fails to begin feedback control within a
manufacturer specified time interval;
A failure or deterioration causes open loop or default
operation; or
Feedback control has used up all of the adjustment allowed
by the manufacturer.
v. EGR Cooler Performance
We are proposing that the OBD system detect a malfunction of the
EGR cooler prior to a reduction from the manufacturer's specified
cooling performance that would cause an engine's emissions to exceed
the emissions thresholds for ``other monitors'' as shown in Table II.B-
1. For engines in which no failure or deterioration of the EGR cooler
could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system would have to detect a malfunction
when the system has no detectable amount of EGR cooling.
c. EGR System Monitoring Conditions
We are proposing that the OBD system monitor continuously for low
EGR flow, high EGR flow, and feedback control malfunctions.
Manufacturers would be required to define the monitoring conditions for
EGR slow response malfunctions such that the minimum performance ratio
requirements discussed in section II.E would be met with the exception
that monitoring must occur every time the monitoring conditions are met
during the driving cycle in lieu of once per driving cycle as required
for most monitors. For purposes of tracking and reporting as required
in section II.E, all monitors used to detect EGR slow response
malfunctions must be tracked separately but reported as a single set of
values as specified in section II.E.\19\
---------------------------------------------------------------------------
\19\ For specific components or systems that have multiple
monitors that are required to be reported (e.g., exhaust gas sensor
bank 1 may have multiple monitors for sensor response or other
sensor characteristics), the OBD system must separately track
numerators and denominators for each of the specific monitors and
report only the corresponding numerator and denominator for the
specific monitor that has the lowest numerical ratio. If two or more
specific monitors have identical ratios, the corresponding numerator
and denominator for the specific monitor that has the highest
denominator shall be reported for the specific component.
---------------------------------------------------------------------------
Manufacturersmay temporarily disable the EGR system check under
specific conditions (e.g., when freezing may affect performance of the
system). To do so, the manufacturer would be required to submit data
and/or engineering analyses that demonstrate that a reliable check
cannot be made when these specific conditions exist.
d. EGR System MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2.
4. Turbo Boost Control System Monitoring
a. Background
Turbochargers are used on internal combustion engines to enhance
performance by increasing the density of the intake air. Some of the
benefits of turbocharging include increased horsepower, improved fuel
economy, and decreased exhaust smoke. Most modern diesel engines take
advantage of these benefits and are equipped with turbocharging
systems. Moreover, smaller turbocharged diesel engines can be used in
place of larger non-turbocharged engines to achieve the desired engine
performance characteristics.
[[Page 3216]]
Exhaust gases passing through the turbine cause it to spin which,
in turn, causes an adjacent centrifugal pump on the same rotating shaft
to spin. The spinning pump serves to compress the intake air thereby
increasing its density. Typically, a boost pressure sensor is located
in the intake manifold to provide a feedback signal of the current
intake manifold pressure. As turbo speed (boost) increases, the
pressure in the intake manifold also increases.
Proper boost control is essential to optimize emission levels. Even
short periods of over-or under-boost can result in undesired air-fuel
ratio excursions and corresponding emission increases. Additionally,
the boost control system directly affects exhaust and intake manifold
pressures. Another critical emission control system, EGR, is very
dependent on these two pressures and generally uses the differential
between them to force exhaust gas into the intake manifold. If the
boost control system is not operating correctly, the exhaust or intake
pressures may not be as expected and the EGR system may not function as
designed. In high-pressure EGR systems, higher exhaust pressures will
generate more EGR flow and, conversely, lower pressures will reduce EGR
flow. A malfunction that causes excessive exhaust pressures (e.g.,
wastegate stuck closed at high engine speed) can produce higher EGR
flowrates at high load conditions and have a negative impact on
emissions.
Manufacturers commonly use charge air coolers to maximize the
benefits of turbocharging and to control NOX emissions. As
the turbocharger compresses the intake air, the temperature of that
intake air increases. This increasing air temperature causes the air to
expand, which conflicts with one of the goals of turbocharging which is
to increase charge air density. Charge air coolers are used to exchange
heat between the compressed air and ambient air (or coolant) and cool
the compressed air. Accordingly, a decrease in charge air cooler
performance can affect emissions by causing higher intake air
temperatures that can lead to higher combustion temperatures and higher
NOX emissions.
One drawback of turbocharging is known as turbo lag. Turbo lag
occurs when the driver attempts to accelerate quickly from a low engine
speed. Since the turbocharger is a mechanical device, a delay exists
from the driver demand for more boost until the exhaust flow can
physically speed up the turbocharger enough to deliver that boost. In
addition to a negative effect on driveability and performance, improper
fueling (e.g., over-fueling) during this lag can cause emission
increases (typically PM).
To decrease the effects of turbo lag, manufacturers design turbos
that spool up quickly at low engine speeds and low exhaust flowrates.
However, designing a turbo that will accelerate quickly from a low
engine speed but will not result in an over-speed/over-boost condition
at higher engine speeds is challenging. That is, as the engine speed
and exhaust flowrates near their maximum, the turbo speed increases to
levels that cause excessive boost pressures and heat that could lead to
engine or turbo damage. To prevent excessive turbine speeds and boost
pressures at higher engine speeds, a wastegate is often used to bypass
part of the exhaust stream around the turbocharger. The wastegate valve
is typically closed at lower engine speeds so that all exhaust is
directed through the turbocharger, thus providing quick response from
the turbocharger when the driver accelerates quickly from low engine
speeds. The wastegate is then opened at higher engine speeds to prevent
engine or turbo damage from an over-speed condition.
An alternative to a wastegate is the variable geometry
turborcharger (VGT). To prevent over-boost conditions and to decrease
turbo lag, VGTs are designed such that the geometry of the turbocharger
changes with engine speed. While various physical mechanisms are used
to achieve the variable geometry, the overall result is essentially the
same. At low engine speeds, the exhaust gas into the turbo is
restricted in a manner that maximizes the use of the available energy
to spin the turbo. This allows the turbo to spool up quickly and
provide good acceleration response. At higher engine speeds, the turbo
geometry changes such that exhaust gas flow into the turbo is not as
restricted. In this configuration, more exhaust can flow through the
turbocharger without causing an over-speed condition. The advantage
that VGTs offer compared to a waste-gated turbocharger is that all
exhaust flow is directed through the turbocharger under all operating
conditions. This can be viewed as maximizing the use of the available
exhaust energy.
b. Turbo Boost Control System Monitoring Requirements
We are proposing that the OBD system monitor the boost pressure
control system on engines so equipped for under and over boost
malfunctions. For engines equipped with variable geometry turbochargers
(VGT), the OBD system would have to monitor the VGT system for slow
response malfunctions. For engines equipped with charge air cooler
systems, the OBD system would have to monitor the charge air cooler
system for cooling system performance malfunctions. The individual
electronic components (e.g., actuators, valves, sensors) that are used
in the boost pressure control system shall be monitored in accordance
with the comprehensive component requirements in section II.D.4.
i. Turbo Underboost Malfunctions
We are proposing that the OBD system detect a malfunction of the
boost pressure control system prior to a decrease from the
manufacturer's commanded boost pressure that would cause an engine's
emissions to exceed the emissions thresholds for ``other monitors'' as
shown in Table II.B-1. For engines in which no failure or deterioration
of the boost pressure control system that causes a decrease in boost
could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system must detect a malfunction when the
system has reached its control limits such that it cannot increase
boost to achieve the commanded boost pressure.
ii. Turbo Overboost Malfunctions
We are proposing that the OBD system detect a malfunction of the
boost pressure control system prior to an increase from the
manufacturer's commanded boost pressure that would cause an engine's
emissions to exceed the emissions thresholds for ``other monitors'' as
shown in Table II.B-1. For engines in which no failure or deterioration
of the boost pressure control system that causes an increase in boost
could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system must detect a malfunction when the
system has reached its control limits such that it cannot decrease
boost to achieve the commanded boost pressure.
iii. VGT Slow Response Malfunctions
We are proposing that the OBD system detect a malfunction prior to
any failure or deterioration in the capability of the VGT system to
achieve the commanded turbocharger geometry within a manufacturer-
specified time that would cause an engine's emissions to exceed the
emissions thresholds for ``other monitors'' as shown in Table II.B-1.
For engines in which no failure or deterioration of the VGT system
response could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system must detect a malfunction of the
VGT system when proper functional response
[[Page 3217]]
of the system to computer commands does not occur.
iv. Turbo Boost Feedback Control Malfunctions
We are proposing that, for engines equipped with feedback control
of the boost pressure system--e.g., control of VGT position, turbine
speed, manifold pressure--the OBD system shall detect a malfunction
when and if:
The system fails to begin feedback control within a
manufacturer specified time interval;
A failure or deterioration causes open loop or default
operation; or
Feedback control has used up all of the adjustment allowed
by the manufacturer.
v. Charge Air Undercooling Malfunctions
We are proposing that the OBD system detect a malfunction of the
charge air cooling system prior to a decrease from the manufacturer's
specified cooling rate that would cause an engine's emissions to exceed
the emissions thresholds for ``other monitors'' as shown in Table II.B-
1. For engines in which no failure or deterioration of the charge air
cooling system that causes a decrease in cooling performance could
result in an engine's emissions exceeding the applicable emissions
thresholds, the OBD system must detect a malfunction when the system
has no detectable amount of charge air cooling.
c. Turbo Boost Control System Monitoring Conditions
We are proposing that the OBD system monitor continuously for
underboost and overboost malfunctions and for boost feedback control
malfunctions. Manufacturers would be required to define the monitoring
conditions for VGT slow response malfunctions such that the minimum
performance ratio requirements discussed in section II.E would be met
with the exception that monitoring must occur every time the monitoring
conditions are met during the driving cycle in lieu of once per driving
cycle as required for most monitors. For purposes of tracking and
reporting as required in section II.E, all monitors used to detect VGT
slow response malfunctions malfunctions must be tracked separately but
reported as a single set of values as discussed in section II.E.\20\
---------------------------------------------------------------------------
\20\ For specific components or systems that have multiple
monitors that are required to be reported (e.g., exhaust gas sensor
bank 1 may have multiple monitors for sensor response or other
sensor characteristics), the OBD system must separately track
numerators and denominators for each of the specific monitors and
report only the corresponding numerator and denominator for the
specific monitor that has the lowest numerical ratio. If two or more
specific monitors have identical ratios, the corresponding numerator
and denominator for the specific monitor that has the highest
denominator shall be reported for the specific component.
---------------------------------------------------------------------------
d. Turbo Boost MIL Illumination and DTC Storage
We are proposing the general MIL illumination and DTC storage
requirements as discussed in section II.A.2.
5. Non-Methane Hydrocarbon (NMHC) Converting Catalyst Monitoring
a. Background
Diesel oxidation catalysts (DOCs) have been used on some nonroad
diesel engines since the 1960s and on some diesel trucks and buses in
the U.S. since the early 1990s. DOCs are generally used for converting
HC and carbon monoxide (CO) emissions to water and CO2 via
an oxidation process. Current DOCs can also be used to convert PM
emissions. DOCs may also be used in conjunction with other
aftertreatment emission controls--such as NOX adsorber
systems, selective catalytic reduction (SCR) systems, and PM filters--
to improve their performance and/or clean up certain reducing agents
that might slip through the system (e.g., the urea used in urea SCR
systems).
b. NMHC Converting Catalyst Monitoring Requirements
We are proposing that the OBD system monitor the NMHC converting
catalyst(s) for proper NMHC conversion capability. We are also
proposing that each catalyst that converts NMHC be monitored either
individually or in combination with others. For engines equipped with
catalyzed diesel particulate filters (CDPFs) that convert NMHC
emissions, the catalyst function of the CDPF must be monitored in
accordance with the CDPF monitoring requirements in section II.B.8.
i. NMHC Converting Catalyst Conversion Efficiency
We are proposing that the OBD system detect an NMHC catalyst
malfunction when the catalyst conversion capability decreases to the
point that NMHC emissions exceed the emissions thresholds for ``NMHC
catalysts'' as shown in Table II.B-1. If no failure or deterioration of
the catalyst NMHC conversion capability could result in an engine's
NMHC emissions exceeding the applicable emissions thresholds, the OBD
system would have to detect a malfunction when the catalyst has no
detectable amount of NMHC conversion capability.
ii. Other Aftertreatment Assistance Functions
For catalysts used to generate an exotherm to assist CDPF
regeneration, we are proposing that the OBD system detect a malfunction
when the catalyst is unable to generate a sufficient exotherm to
achieve that regeneration. For catalysts used to generate a feedgas
constituency to assist SCR systems (e.g., to increase NO2
concentration upstream of an SCR system), the OBD system would have to
detect a malfunction when the catalyst is unable to generate the
necessary feedgas constituents for proper SCR system operation. For
catalysts located downstream of a CDPF and used to convert NMHC
emissions during a CDPF regeneration event, the OBD system would be
required to detect a malfunction when the catalyst has no detectable
amount of NMHC conversion capability.
c. NMHC Converting Catalyst Monitoring Conditions
Manufacturers would be required to define the monitoring conditions
for NMHC converting catalyst malfunctions such that the minimum
performance ratio requirements discussed in section II.E would be met.
For purposes of tracking and reporting as discussed in section II.E,
all monitors used to detect NMHC converting catalyst malfunctions must
be tracked separately but reported as a single set of values as
discussed in section II.E.\21\
---------------------------------------------------------------------------
\21\ For specific components or systems that have multiple
monitors that are required to be reported (e.g., exhaust gas sensor
bank 1 may have multiple monitors for sensor response or other
sensor characteristics), the OBD system must separately track
numerators and denominators for each of the specific monitors and
report only the corresponding numerator and denominator for the
specific monitor that has the lowest numerical ratio. If two or more
specific monitors have identical ratios, the corresponding numerator
and denominator for the specific monitor that has the highest
denominator shall be reported for the specific component.
---------------------------------------------------------------------------
d. NMHC Converting Catalyst MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage discussed in section II.A.2. Note that the monitoring
method for the catalyst(s) must be capable of detecting all instances,
except diagnostic self-clearing, when a catalyst DTC has been cleared
but the catalyst has not been replaced (e.g., catalyst over temperature
histogram approaches are not acceptable).\22\
---------------------------------------------------------------------------
\22\ For gasoline catalyst monitoring, manufacturers generally
use what is called an exponentially weighted moving average (EWMA)
approach to making decisions about the catalyst's pass/fail status.
This approach monitors the catalyst and ``saves'' that information.
The next time it monitors the catalyst, it saves that information
along with the previous information, placing a higher weighting on
the most recent information. This is done every time the OBD system
monitors the catalyst and the EWMA saves six or seven monitoring
events before making a decision. Importantly, once there exists six
or seven pieces of information, every monitoring event can result in
a decision because the EWMA is always using the previous six or
seven events. Unfortunately, if a service technician clears the data
with a scan tool, it is going to take six or seven monitoring events
before the catalyst monitor can make a decision on the pass/fail
status of the catalyst. So, we want to be sure that, in addition to
the EWMA aspect of the catalyst monitor, there exists a way of
determining quickly that someone has cleared the data but perhaps
did not actually repair the catalyst. This is required to help
prevent against DTC clearing without fixing a failed catalyst as a
means of passing an inspection & maintenance test.
---------------------------------------------------------------------------
[[Page 3218]]
6. Selective Catalytic Reduction (SCR) and Lean NOX Catalyst
Monitoring
a. Background
Selective Catalytic Reduction (SCR) catalysts that use ammonia as a
NOX reductant have been used for stationary source
NOX control for a number of years. Frequently, urea is used
as the source of ammonia for SCR catalysts, and such systems are
commonly referred to as Urea SCR systems. In recent years, considerable
effort has been invested in developing urea SCR systems that could be
applied to heavy-duty diesel vehicles with low sulfur diesel fuel. We
now expect that urea SCR systems will be introduced in Europe to comply
with the EURO IV heavy-duty diesel emission standards. Such systems
have been introduced in the past year by some heavy-duty diesel engine
manufacturers both in Europe and in Japan.
SCR catalyst systems require an accurate urea control system to
inject precise amounts of reductant. An injection rate that is too low
may result in lower NOX conversions while an injection that
is too high may release unwanted ammonia emissions--referred to as
ammonia slip--to the atmosphere. In general, ammonia to NOX
ratios of around 1:1 are used to provide the highest NOX
conversion rates with minimal ammonia slip. Therefore, injecting just
the right amount of ammonia appropriate for the amount of
NOX in the exhaust is very important. This can be
challenging in a highway application because on-road diesel engines
operate over a variety of speeds and loads. This makes the use of
closed-loop feedback systems for reductant metering very attractive.
This can be achieved, for example, with a dedicated NOX
sensor in the exhaust so that the NOX concentration can be
accurately known. With an accurate fast response NOX sensor,
closed-loop control of the ammonia injection can be used to achieve and
maintain the desired ammonia/NOX ratios in the SCR catalyst
for the high NOX conversion efficiencies necessary to
achieve the 2010 emission standards under various engine operating
conditions.
Some have estimated that achieving the 2010 NOX emission
standards with SCR systems will require NOX sensors that can
measure NOX levels accurately in the 20 to 40 ppm range with
little cross sensitivity to ammonia. Some in industry have even stated
a desire for accuracy in the two to three ppm range. Suppliers have
been developing NOX sensors capable of measuring
NOX in the 0 to 100 ppm range with +/-5 ppm accuracy which
we believe will be available by 2010.\23\ Regarding cross-sensitivity
to ammonia, work has been done that indicates ammonia and
NOX measurements can be independently measured by
conditioning the output signal.\24\ This signal conditioning method
resulted in a linear output for both ammonia and NOX from
the NOX sensor downstream of the catalyst.
---------------------------------------------------------------------------
\23\ Draft Technical Support Document, HDOBD NPRM, EPA420-D-06-
006, Docket ID EPA-HQ-OAR-2005-0047-0008.
\24\ Schaer, C. M., Onder, C. H., Geering, H. P., and Elsener,
M., ``Control of a Urea SCR Catalytic Converter System for a Mobile
Heavy-Duty Diesel Engine,'' SAE Paper 2003-01-0776 which may be
obtained from Society of Automotive Engineers International, 400
Commonwealth Dr., Warrendale, PA, 15096-0001.
---------------------------------------------------------------------------
For SCR systems, closed-loop control of the reductant injection may
require the use of two NOX sensors. The first NOX
sensor would be located upstream of the catalyst and the reductant
injection point would be used for measuring the engine-out
NOX emissions and determining the amount of reductant
injection needed to reduce emissions. The second NOX sensor
located downstream of the catalyst would be used for measuring the
amount of ammonia and NOX emissions exiting the catalyst and
providing feedback to the reductant injection control system. If the
downstream NOX sensor detects too much NOX
emissions exiting the catalyst, the control system can inject higher
quantities of reductant. Conversely, if the downstream NOX
sensor detects too much ammonia slip exiting the catalyst, the control
system can decrease the amount of reductant injection.
In addition to exhaust NOX levels, another important
parameter for achieving high NOX conversion rates with
minimum ammonia slip is catalyst temperature. SCR catalysts have a
defined temperature range where they are most effective. For example,
platinum catalysts are effective between 175 and 250 degrees Celsius,
vanadium catalysts are effective between 300 and 450 degrees Celsius,
and zeolite catalysts are most effective between 350 and 600 degrees
Celsius. To determine exhaust catalyst temperature for reductant
control purposes, manufacturers are likely to use temperature sensors
placed in the exhaust system. We project that only one temperature
sensor positioned just downstream of the SCR system will be utilized
for reductant injection control purposes.
Production SCR catalyst systems may also contain auxiliary
catalysts to improve the overall emissions control capability of the
system. An oxidation catalyst is often positioned downstream of the SCR
catalyst to help control ammonia slip on systems without closed-loop
control of ammonia injection. The use of a ``guard'' catalyst could
allow higher ammonia injection levels, thereby increasing the
NOX conversion efficiency without releasing un-reacted
ammonia into the exhaust. The guard catalyst can also reduce HC and CO
emission levels and diesel odors. However, increased N2O emissions may
occur and NOX emission levels may actually increase if too
much ammonia is oxidized in the catalyst. Some SCR systems may also
include an oxidation catalyst upstream of the SCR catalyst and urea
injection point to generate NO2 for lowering the effective operating
temperature and/or volume of the SCR catalyst. Studies have indicated
that increasing the NO2 content in the exhaust stream can reduce the
SCR temperature requirements by about 100 degrees Celsius.\25\ This
``pre-oxidation'' catalyst also has the added benefit of reducing HC
emissions.
---------------------------------------------------------------------------
\25\ Walker, A. P., Chandler, G. R., Cooper, B. J., et al., ``An
Integrated SCR and Continuously Regenerating Trap System to Meet
Future NOX and PM Legislation,'' SAE Paper 2000-01-0188
which may be obtained from Society of Automotive Engineers
International, 400 Commonwealth Dr., Warrendale, PA, 15096-0001.
---------------------------------------------------------------------------
b. SCR and Lean NOX Catalyst Monitoring Requirements
We are proposing that the OBD system monitor SCR catalysts and lean
NOX catalysts for proper conversion capability. We are also
proposing that each catalyst that converts NOX be monitored
either individually or in combination with others. For engines equipped
with SCR systems or other catalyst systems that utilize an active/
intrusive reductant injection (e.g., active lean NOX
catalysts utilizing diesel fuel
[[Page 3219]]
injection), the OBD system would be required to monitor the active/
intrusive reductant injection system for proper performance. The
individual electronic components (e.g., actuators, valves, sensors,
heaters, pumps) in the active/intrusive reductant injection system must
be monitored in accordance with the comprehensive component
requirements in section II.D.4.
i. Catalyst Conversion Efficiency Malfunctions
We are proposing that the OBD system detect a catalyst malfunction
when the catalyst conversion capability decreases to the point that
would cause an engine's NOX emissions to exceed any of the
applicable emissions thresholds for ``NOX Catalyst Systems''
as shown in Table II.B-1. If no failure or deterioration of the
catalyst NOX conversion capability could result in an
engine's NOX emissions exceeding any of the applicable
emissions thresholds, the OBD system would have to detect a malfunction
when the catalyst has no detectable amount of NOX conversion
capability.
ii. Active/Intrusive Reductant Injection System Malfunctions
Specific to SCR and other active/intrusive reductant injection
system performance, we are proposing that the OBD system detect a
malfunction prior to any failure or deterioration of the system to
regulate reductant delivery properly (e.g., urea injection, separate
injector fuel injection, post injection of fuel, air assisted
injection/mixing) that would cause an engine's NOX emissions
to exceed any of the applicable emissions thresholds for
``NOX Catalyst Systems'' as shown in Table II.B-1. As above,
if no failure or deterioration of the reductant delivery system could
result in an engine's NOX emissions exceeding the applicable
emissions thresholds, the OBD system would have to detect a malfunction
when the system has reached its control limits such that it is no
longer able to deliver the desired quantity of reductant.
If the system uses a reductant other than the fuel used for the
engine or uses a reservoir/tank for the reductant that is separate from
the fuel tank used for the engine, the OBD system must detect a
malfunction when there is no longer sufficient reductant available
(e.g., the reductant tank is empty). If the system uses a reservoir/
tank for the reductant that is separate from the fuel tank used for the
engine, the OBD system must detect a malfunction when an improper
reductant is used in the reductant reservoir/tank (e.g., the reductant
tank is filled with something other than the proper reductant).
iii. SCR and Lean NOX Catalyst Feedback Control System
Malfunctions
If the engine is equipped with feedback control of the reductant
injection, we are proposing that the OBD system detect a malfunction
when and if:
The system fails to begin feedback control within a
manufacturer specified time interval;
A failure or deterioration causes open loop or default
operation; or
Feedback control has used up all of the adjustment allowed
by the manufacturer.
c. SCR and Lean NOX Catalyst Monitoring Conditions
Manufacturers would be required to define the monitoring conditions
for catalyst conversion efficiency malfunctions such that the minimum
performance ratio requirements discussed in section II.E would be met.
For purposes of tracking and reporting as required in section II.E, all
monitors used to detect catalyst conversion efficiency malfunctions
must be tracked separately but reported as a single set of values as
specified in section II.E.\26\ We are also proposing that the OBD
system monitor continuously for active/intrusive reductant injection
system malfunctions. Manufacturers would be required to monitor
continuously the active/intrusive reductant delivery system.
---------------------------------------------------------------------------
\26\ For specific components or systems that have multiple
monitors that are required to be reported (e.g., exhaust gas sensor
bank 1 may have multiple monitors for sensor response or other
sensor characteristics), the OBD system must separately track
numerators and denominators for each of the specific monitors and
report only the corresponding numerator and denominator for the
specific monitor that has the lowest numerical ratio. If two or more
specific monitors have identical ratios, the corresponding numerator
and denominator for the specific monitor that has the highest
denominator shall be reported for the specific component.
---------------------------------------------------------------------------
d. SCR and Lean NOX Catalyst MIL Illumination and DTC
Storage
We are proposing the general MIL illumination and DTC storage
requirements presented in section II.A.2 with the exception of active/
intrusive reductant injection related malfunctions. If the OBD system
is capable of discerning that a system malfunction is being caused by
an empty reductant tank, the manufacturer may delay illumination of the
MIL if the vehicle is equipped with an alternative indicator for
notifying the vehicle operator of the malfunction. The manufacturer
would be required to demonstrate that: The alternative indicator is of
sufficient illumination and location to be readily visible to the
operator under all lighting conditions; and the alternative indicator
provides equivalent assurance that a vehicle operator will be promptly
notified; and, that corrective action would be undertaken. If the
vehicle is not equipped with an alternative indicator and the MIL
illuminates, the MIL may be immediately extinguished and the
corresponding DTC erased once the OBD system has verified that the
reductant tank has been properly refilled and the MIL has not been
illuminated for any other type of malfunction. The Administrator may
approve other strategies that provide equivalent assurance that a
vehicle operator will be promptly notified and that corrective action
will be undertaken.
The monitoring method for the catalyst(s) would have to be capable
of detecting all instances, except diagnostic self-clearing, when a
catalyst DTC has been cleared but the catalyst has not been replaced
(e.g., catalyst over temperature histogram approaches are not
acceptable).
7. NOX Adsorber System Monitoring
a. Background
NOX adsorbers, or lean NOX traps (LNT), work
to control NOX emissions by storing NOX on the
surface of the catalyst during the lean engine operation typical of
diesel engines and then by undergoing subsequent brief rich
regeneration events where the NOX is released and reduced
across a precious metal catalyst.
NOX adsorber systems generally consist of a conventional
three-way catalyst function (e.g., platinum) with NOX
storage components (i.e., adsorbents) incorporated into the washcoat.
Three-way catalysts convert NOX emissions as well as HC and
CO emissions (hence the name three-way) by promoting oxidation of HC
and CO to H2O and CO2 using the oxidation
potential of the NOX pollutant and, in the process, reducing
the NOX emissions to nitrogen, N2. Said another
way, three-way catalysts work with exhaust conditions where the net
oxidizing and reducing chemistry of the exhaust is approximately equal,
allowing the catalyst to promote complete oxidation/reduction reactions
to the desired exhaust components of CO2, H2O,
and N2. The oxidizing potential in the exhaust comes from
NOX emissions and any feedgas oxygen (O2) not
consumed during combustion. The reducing potential in the exhaust
[[Page 3220]]
comes from HC and CO emissions, which represent products of incomplete
combustion. Operation of the engine to ensure that the oxidizing and
reducing potential of the combustion and exhaust conditions is
precisely balanced is referred to as stoichiometric engine operation.
Because diesel engines run lean of stoichiometric operation, the
NOX emissions are stored, or absorbed--via chemical reaction
with alkaline earth metals such as barium nitrate in the washcoat--and
then released during rich operation for conversion to N2.
This NOX release during rich operation is referred to as a
regeneration event. The rich operating conditions required for
NOX regeneration, which generally last for several seconds,
are typically achieved using a combination of intake air throttling (to
reduce the amount of intake air), exhaust gas recirculation, and post-
combustion fuel injection.
NOX adsorber systems have demonstrated NOX
reduction efficiencies from 50 percent to in excess of 90 percent. This
efficiency has been found to be highly dependent on the fuel sulfur
content because NOX adsorbers are extremely sensitive to
sulfur. The NOX adsorption material has an even greater
affinity for sulfur compounds than NOX. Thus, sulfur
compounds can saturate the adsorber and limit the number of active
sites for NOX adsorption, thereby lowering the
NOX reduction efficiency. Accordingly, low sulfur fuel is
required to achieve the greatest NOX reduction efficiencies.
Although new adsorber washcoat materials are being developed with a
higher resistance to sulfur poisoning and ultra-low sulfur fuel will be
the norm by 2010, NOX adsorber systems will still need to
purge the stored sulfur from the storage bed by a process referred to
as desulfation. Because the desulfation process takes longer (e.g.,
several minutes) and requires more fuel and heat than the
NOX regeneration step, permanent thermal degradation of the
NOX adsorber and fuel economy penalties may result from
desulfation events happening with excessive frequency. However, if
desulfation is not done frequently enough, NOX storage
capacity would be compromised and fuel economy penalties would be
incurred from excessive attempts at NOX regeneration.
In order to achieve and maintain high NOX conversion
efficiencies while limiting negative impacts on fuel economy and
driveability, vehicles with NOX adsorber systems will
require precise air/fuel control in the engine and in the exhaust
stream. Diesel manufacturers are expected to utilize NOX
sensors and temperature sensors to provide the most precise closed-loop
control for the NOX adsorber system. If NOX
sensors are not used to control the NOX adsorber system,
manufacturers could use wide-range air-fuel (A/F) sensors located
upstream and downstream of the adsorber as a substitute. However, A/F
sensors cannot provide an instantaneous indication of tailpipe
NOX levels, which would allow the control system to
precisely determine when the adsorber system is filled to capacity and
regeneration should be initiated. If A/F sensors are used in lieu of
NOX sensors, an estimation of engine-out NOX
emissions and their subsequent storage in the NOX adsorber
can be achieved indirectly through modeling.
b. NOX Adsorber System Monitoring Requirements
We are proposing that the OBD system monitor the NOX
adsorber on engines so equipped for proper performance. For engines
equipped with active/intrusive injection (e.g., in-exhaust fuel and/or
air injection) to achieve NOX regeneration, the OBD system
would have to monitor the active/intrusive injection system for proper
performance. The individual electronic components (e.g., injectors,
valves, sensors) that are used in the active/intrusive injection system
would have to be monitored in accordance with the comprehensive
component requirements in section II.D.4.
i. NOX Adsorber Capability Malfunctions
We are proposing that the OBD system detect a NOX
adsorber malfunction when its capability--i.e., its combined adsorption
and conversion capability--decreases to the point that would cause an
engine's NOX emissions to exceed the applicable emissions
thresholds for ``NOX Catalyst Systems'' as shown in Table
II.B-1. If no failure or deterioration of the NOX adsorber
capability could result in an engine's NOX emissions
exceeding the applicable emissions thresholds, the OBD system would
have to detect a malfunction when the system has no detectable amount
of NOX adsorber capability.
ii. Active/Intrusive Reductant Injection System Malfunctions
For NOX adsorber systems that use active/intrusive
injection (e.g., in-cylinder post fuel injection, in-exhaust air-
assisted fuel injection) to achieve desorption of the NOX
adsorber, the OBD system would have to detect a malfunction if any
failure or deterioration of the injection system's ability to properly
regulate injection causes the system to be unable to achieve desorption
of the NOX adsorber.
iii. NOX Adsorber Feedback Control System Malfunctions
If the engine is equipped with feedback control of the reductant
injection (e.g., feedback control of injection quantity, time), we are
proposing that the OBD system detect a malfunction when and if:
The system fails to begin feedback control within a
manufacturer specified time interval;
A failure or deterioration causes open loop or default
operation; or
Feedback control has used up all of the adjustment allowed
by the manufacturer.
c. NOX Adsorber System Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for NOX adsorber capability malfunctions such
that the minimum performance ratio requirements discussed in section
II.E would be met. For purposes of tracking and reporting as required
in section II.E, all monitors used to detect NOX adsorber
capability malfunctions must be tracked separately but reported as a
single set of values as specified in section II.E.\27\ We are also
proposing that the OBD system monitor continuously for active/intrusive
reductant injection and feedback control system malfunctions.
---------------------------------------------------------------------------
\27\ For specific components or systems that have multiple
monitors that are required to be reported (e.g., exhaust gas sensor
bank 1 may have multiple monitors for sensor response or other
sensor characteristics), the OBD system must separately track
numerators and denominators for each of the specific monitors and
report only the corresponding numerator and denominator for the
specific monitor that has the lowest numerical ratio. If two or more
specific monitors have identical ratios, the corresponding numerator
and denominator for the specific monitor that has the highest
denominator shall be reported for the specific component.
---------------------------------------------------------------------------
d. NOX Adsorber System MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage discussed in section II.A.2.
8. Diesel Particulate Filter (DPF) System Monitoring
a. Background
Diesel particulate filters control diesel PM by capturing the soot
(solid carbon) portion of PM in a filter media, typically a ceramic
wall flow substrate, and then by oxidizing (burning) it in the oxygen-
rich atmosphere of diesel exhaust.\28\ In aggregate over a driving
cycle, the PM must be burned at a rate equal to or
[[Page 3221]]
greater than its accumulation rate, or the DPF will clog. Given low
sulfur diesel fuel (diesel fuel with a sulfur content of 15 ppm or
lower), highly active catalytic metals (e.g., platinum) can be used to
promote soot oxidation. This method of PM filter regeneration, called
passive regeneration, is the primary means of soot oxidation that we
project industry will use in 2007/2010.
---------------------------------------------------------------------------
\28\ See ``Regulatory Impact Analysis: Heavy-Duty Engine and
Vehicle Standards and Highway Diesel Fuel Sulfur Control
Requirements;'' EPA420-R-00-026; December 2000 at Chapter III for a
more complete description of DPFs.
---------------------------------------------------------------------------
The DPF technology has proven itself in tens of thousands of
retrofit applications where low sulfur diesel fuel is already
available. More than a million light-duty passenger cars in Europe now
have diesel particulate filters. DPFs are considered the most effective
control technology for the reduction of particulate emissions and can
typically achieve PM reductions in excess of 90 percent.
In order to maintain the performance of the DPF and the engine, the
trapped PM must be periodically removed before too much particulate is
accumulated and exhaust backpressure reaches unacceptable levels. The
process of periodically removing accumulated PM from the DPF is known
as ``regeneration'' and is very important for maintaining low PM
emission levels. DPF regeneration can be passive (i.e., occur
continuously during regular operation of the filter), active (i.e.,
occur on a controlled, periodic basis after a predetermined quantity of
particulates have been accumulated), or a combination of the two. With
passive regeneration, the oxidizing catalyst material on the DPF
substrate serves to lower the temperature for oxidizing PM. This allows
the DPF to continuously oxidize trapped PM material during normal
driving. In contrast, active systems utilize an external heat source--
such as an electric heater or fuel burner--to facilitate DPF
regeneration. We are projecting that virtually all DPF systems will
have some sort of active regeneration mechanism as a backup mechanism
should operating conditions not be conducive for passive regeneration.
One of the key considerations for a DPF regeneration control system
is the amount of soot quantity that is stored in the DPF (often called
soot loading). If too much soot is stored when regeneration is
activated, the soot can burn uncontrollably and DPF substrate could be
damaged via melting or cracking. Conversely, activating regeneration
when there is too little trapped soot will not ensure good combustion
propagation which would effectively waste the energy (fuel) used to
initiate the regeneration. Another important consideration in the
control system design is the fuel economy penalty involved with DPF
regeneration. Prolonged operation with high backpressures in the
exhaust and regenerations occurring too frequently are both detrimental
to fuel economy and DPF durability. Therefore, DPF system designers
will need to carefully balance the regeneration frequency with various
conflicting factors. To optimize the trap regeneration for these design
factors, the DPF regeneration control system is projected to
incorporate both pressure sensors and temperature sensors to model soot
loading and other phenomena.\29\ Through the information provided by
these sensors, designers can optimize the DPF for high effectiveness
and maximum durability while minimizing fuel economy and performance
penalties.
---------------------------------------------------------------------------
\29\ Salvat, O., Marez, P., and Belot, G., ``Passenger Car
Serial Application of a Particulate Filter System on a Common Rail
Direct Injection Diesel Engine,'' SAE Paper 2000-01-0473 which may
be obtained from Society of Automotive Engineers International, 400
Commonwealth Dr., Warrendale, PA, 15096-0001.
---------------------------------------------------------------------------
b. DPF System Monitoring Requirements
We are proposing that the OBD system monitor the DPF on engines so-
equipped for proper performance.\30\ For engines equipped with active
regeneration systems that utilize an active/intrusive injection (e.g.,
in-exhaust fuel injection, in-exhaust fuel/air burner), the OBD system
would have to monitor the active/intrusive injection system for proper
performance. The individual electronic components (e.g., injectors,
valves, sensors) that are used in the active/intrusive injection system
must be monitored in accordance with the comprehensive component
requirements in section II.D.4.
---------------------------------------------------------------------------
\30\ Note that these requirements would also apply to a
catalyzed diesel particulate filter (CDPF). We use the more common
term DPF throughout this discussion.
---------------------------------------------------------------------------
i. PM Filtering Performance
We are proposing that the OBD system detect a malfunction prior to
a decrease in the filtering capability of the DPF (e.g., cracking,
melting, etc.) that would cause an engine's PM emissions to exceed the
applicable emissions thresholds for ``DPF Systems'' as shown in Table
II.B-1. If no failure or deterioration of the PM filtering performance
could result in an engine's PM emissions exceeding the applicable
emissions thresholds, the OBD system would have to detect a malfunction
when no detectable amount of PM filtering occurs.
ii. DPF Regeneration Frequency Malfunctions--Too Frequent
We are proposing that the OBD system detect a malfunction when the
DPF regeneration frequency increases from--i.e., occurs more often
than--the manufacturer's specified regeneration frequency to a level
such that it would cause an engine's NMHC emissions to exceed the
applicable emissions threshold for ``DPF Systems'' as shown in Table
II.B-1. If no such regeneration frequency exists that could cause NMHC
emissions to exceed the applicable emission threshold, the OBD system
would have to detect a malfunction when the PM filter regeneration
frequency exceeds the manufacturer's specified design limits for
allowable regeneration frequency.
iii. DPF Incomplete Regeneration Malfunctions
We are proposing that the OBD system detect a regeneration
malfunction when the DPF does not properly regenerate under
manufacturer-defined conditions where regeneration is designed to
occur.
iv. DPF NMHC Conversion Efficiency Malfunctions
We are proposing that, for any DPF that serves to convert NMHC
emissions, the OBD system must monitor the NMHC converting function of
the DPF and detect a malfunction when the NMHC conversion capability
decreases to the point that NMHC emissions exceed the NMHC threshold
for ``DPF Systems'' as shown in Table II.B-1. If no failure or
deterioration of the NMHC conversion capability could result in NMHC
emissions exceeding the applicable NMHC threshold, the OBD system would
have to detect a malfunction when the system has no detectable amount
of NMHC conversion capability.
v. DPF Missing Substrate Malfunctions
We are proposing that the OBD system detect a malfunction if either
the DPF substrate is completely destroyed, removed, or missing, or if
the DPF assembly has been replaced with a muffler or straight pipe.
vi. DPF Active/Intrusive Injection System Malfunctions
We are proposing that, for systems that utilize active/intrusive
injection (e.g., in-cylinder post fuel injection, in-exhaust air-
assisted fuel injection) to achieve DPF regeneration, the OBD system
detect a malfunction if any
[[Page 3222]]
failure or deterioration of the injection system's ability to properly
regulate injection causes the system to be unable to achieve DPF
regeneration.
vii. DPF Regeneration Feedback Control System Malfunctions
We are proposing that, if the engine is equipped with feedback
control of the DPF regeneration (e.g., feedback control of oxidation
catalyst inlet temperature, PM filter inlet or outlet temperature, in-
cylinder or in-exhaust fuel injection), the OBD system must detect a
malfunction when and if:
The system fails to begin feedback control within a
manufacturer specified time interval;
A failure or deterioration causes open loop or default
operation; or
Feedback control has used up all of the adjustment allowed
by the manufacturer.
c. DPF System Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for all DPF related malfunctions such that the minimum
performance ratio requirements discussed in section II.E would be met
with the exception that monitoring must occur every time the monitoring
conditions are met during the driving cycle rather than once per
driving cycle as required for most monitors. For purposes of tracking
and reporting as required in section II.E, all monitors used to detect
all DPF related malfunctions would have to be tracked separately but
reported as a single set of values as specified in section II.E.\31\
---------------------------------------------------------------------------
\31\ For specific components or systems that have multiple
monitors that are required to be reported (e.g., exhaust gas sensor
bank 1 may have multiple monitors for sensor response or other
sensor characteristics), the OBD system must separately track
numerators and denominators for each of the specific monitors and
report only the corresponding numerator and denominator for the
specific monitor that has the lowest numerical ratio. If two or more
specific monitors have identical ratios, the corresponding numerator
and denominator for the specific monitor that has the highest
denominator shall be reported for the specific component.
---------------------------------------------------------------------------
d. DPF System MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2.
9. Exhaust Gas Sensor Monitoring
a. Background
Exhaust gas sensors (e.g., oxygen sensors, wide-range air-fuel (A/
F) sensors, NOX sensors) are important to the emission
control system of vehicles. These sensors are used for enhancing the
performance of several emission control technologies (e.g., catalysts,
EGR systems). We expect that both oxygen sensors and wide range A/F
sensors may be used by heavy-duty manufacturers to optimize their
emission control technologies. We would expect that, in addition to
their emissions control functions, these sensors will also be used to
satisfy many of the proposed HDOBD monitoring requirements, such as
fuel system monitoring, catalyst monitoring, and EGR system monitoring.
NOX sensors may also be used for optimization of several
diesel emission control technologies, such as NOX adsorbers
and selective catalytic reduction (SCR) systems. Since an exhaust gas
sensor can be a critical component of a vehicle's fuel and emission
control system, the proper performance of this component needs to be
assured to maintain low emissions. The reliance on these sensors for
emissions control and OBD monitoring makes it important that any
malfunction that adversely affects the performance of any of these
sensors be detected by the OBD system.
b. Exhaust Gas Sensor Monitoring Requirements
We are proposing that the OBD system monitor all exhaust gas
sensors (e.g., oxygen, air-fuel ratio, NOX) used either for
emission control system feedback (e.g., EGR control/feedback, SCR
control/feedback, NOX adsorber control/feedback), or as a
monitoring device, for proper output signal, activity, response rate,
and any other parameter that can affect emissions. For engines equipped
with heated exhaust gas sensors, the OBD system would have to monitor
the heater for proper performance.
i. Air/Fuel Ratio Sensor Malfunctions
For all air/fuel ratio sensors, we are proposing the following:
Circuit malfunctions: The OBD system must detect
malfunctions of the sensor caused by either a lack of circuit
continuity or out-of-range values.
Feedback malfunctions: The OBD system must detect a
malfunction of the sensor when a sensor failure or deterioration causes
an emissions control system--e.g., the EGR, SCR, or NOX
adsorber systems--to stop using that sensor as a feedback input (e.g.,
causes default or open-loop operation).
Monitoring capability: To the extent feasible, the OBD
system must detect a malfunction of the sensor when the sensor output
voltage, resistance, impedance, current, amplitude, activity, offset,
or other characteristics are no longer sufficient for use as an OBD
system monitoring device (e.g., for catalyst, EGR, SCR, or
NOX adsorber monitoring).
Specifically for sensors located upstream of an aftertreatment
device, we are proposing the following:
Sensor performance malfunctions: The OBD system must
detect a malfunction prior to any failure or deterioration of the
sensor voltage, resistance, impedance, current, response rate,
amplitude, offset, or other characteristic(s) that would cause an
engine's emissions to exceed the applicable emissions thresholds for
``Other Monitors'' as shown in Table II.B-1.
Specifically for sensors located downstream of an aftertreatment
device, we are proposing the following:
Sensor performance malfunctions: The OBD system must
detect a malfunction prior to any failure or deterioration of the
sensor voltage, resistance, impedance, current, response rate,
amplitude, offset, or other characteristic(s) that would cause an
engine's emissions to exceed the applicable emissions thresholds for
``Air-fuel ratio sensors downstream of aftertreatment devices'' as
shown in Table II.B-1.
ii. NOX Sensor Malfunctions
For NOX sensors, we are proposing the following:
Sensor performance malfunctions: The OBD system must
detect a malfunction prior to any failure or deterioration of the
sensor voltage, resistance, impedance, current, response rate,
amplitude, offset, or other characteristic(s) that would cause an
engine's emissions to exceed the applicable emissions thresholds for
``NOX sensors'' as shown in Table II.B-1.
Circuit malfunctions: The OBD system must detect
malfunctions of the sensor caused by either a lack of circuit
continuity or out-of-range values.
Feedback malfunctions: The OBD system shall detect a
malfunction of the sensor when a sensor failure or deterioration causes
an emission control--e.g., the EGR, SCR, or NOX adsorber
systems--to stop using that sensor as a feedback input (e.g., causes
default or open-loop operation).
Monitoring capability: To the extent feasible, the OBD
system must detect a malfunction of the sensor when the sensor output
voltage, resistance, impedance, current, amplitude, activity, offset,
or other characteristics are no longer sufficient for use as an OBD
system monitoring device (e.g., for catalyst, EGR, SCR, or
NOX adsorber monitoring).
[[Page 3223]]
iii. Other Exhaust Gas Sensor Malfunctions
For other exhaust gas sensors, we are proposing that the
manufacturer submit a monitoring plan to the Administrator for
approval. The Administrator would approve the request upon determining
that the manufacturer has submitted data and an engineering evaluation
that demonstrate that the monitoring plan is as reliable and effective
as the monitoring plan required for air/fuel ratio sensors and
NOX sensors.
iv. Exhaust Gas Sensor Heater Malfunctions
We are proposing that the OBD system detect a malfunction of the
heater performance when the current or voltage drop in the heater
circuit is no longer within the manufacturer's specified limits for
normal operation (i.e., within the criteria required to be met by the
component vendor for heater circuit performance at high mileage). The
manufacturer may use other malfunction criteria for heater performance
malfunctions. To do so, the manufacturer would be required to submit
data and/or engineering analyses that demonstrate that the monitoring
reliability and timeliness would be equivalent to the criteria stated
here. Further, the OBD system would be required to detect malfunctions
of the heater circuit including open or short circuits that conflict
with the commanded state of the heater (e.g., shorted to 12 Volts when
commanded to 0 Volts (ground)).
c. Exhaust Gas Sensor Monitoring Conditions
For exhaust gas sensor performance malfunctions, we are proposing
that manufacturers define the monitoring conditions such that the
minimum performance ratio requirements discussed in section II.E would
be met. For purposes of tracking and reporting as required in section
II.E, all monitors used to detect sensor performance malfunctions would
have to be tracked separately but reported as a single set of values as
specified in section II.E.\32\
---------------------------------------------------------------------------
\32\ For specific components or systems that have multiple
monitors that are required to be reported (e.g., exhaust gas sensor
bank 1 may have multiple monitors for sensor response or other
sensor characteristics), the OBD system must separately track
numerators and denominators for each of the specific monitors and
report only the corresponding numerator and denominator for the
specific monitor that has the lowest numerical ratio. If two or more
specific monitors have identical ratios, the corresponding numerator
and denominator for the specific monitor that has the highest
denominator shall be reported for the specific component.
---------------------------------------------------------------------------
For exhaust gas sensor monitoring capability malfunctions,
manufacturers would have to define the monitoring conditions such that
the minimum performance ratio requirements discussed in section II.E
would be met with the exception that monitoring must occur every time
the monitoring conditions are met during the driving cycle rather than
once per driving cycle as required for most monitors.
For exhaust gas sensor circuit malfunctions and feedback
malfunctions, monitoring must be conducted continuously.
The manufacturer may disable continuous exhaust gas sensor
monitoring when an exhaust gas sensor malfunction cannot be
distinguished from other effects (e.g., disable ``out-of-range low''
monitoring during fuel cut conditions). To do so, the manufacturer
would be required to submit test data and/or engineering analyses that
demonstrate that a properly functioning sensor cannot be distinguished
from a malfunctioning sensor and that the disablement interval is
limited only to that necessary for avoiding a false detection.
For exhaust gas sensor heater malfunctions, manufacturers must
define monitoring conditions such that the minimum performance ratio
requirements discussed in section II.E would be met. Monitoring for
sensor heater circuit malfunctions must be conducted continuously.
d. Exhaust Gas Sensor MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2.
C. Monitoring Requirements and Timelines for Gasoline/Spark-Ignition
Engines
Table II.C-1 summarizes the proposed gasoline fueled spark ignition
emissions thresholds at which point a component or system has failed to
the point of requiring an illuminated MIL and a stored DTC. Table II.C-
2 summarizes the proposed implementation schedule for these
thresholds--i.e., the proposed certification requirements and in-use
liabilities. More detail regarding the specific monitoring
requirements, implementation schedules, and liabilities can be found in
the sections that follow.
Table II.C-1.--Proposed Emissions Thresholds for Gasoline Fueled SI Engines Over 14,000 Pounds
----------------------------------------------------------------------------------------------------------------
Component/Monitor MY NMHC CO NOX
----------------------------------------------------------------------------------------------------------------
Catalytic converter system....... 2010+............. 1.75x............. .................. 1.75x
``Other monitors'' with emissions 2010+............. 1.5x.............. 1.5x.............. 1.5x
thresholds (see section II.C).
Evaporative emissions control 2010+............. 0.150 inch leak ..
system.
----------------------------------------------------------------------------------------------------------------
Notes: MY=Model Year; 1.75x means a multiple of 1.75 times the applicable emissions standard; not all proposed
monitors have emissions thresholds but instead rely on functionality and rationality checks as described in
section II.D.4. The evaporative emissions control system threshold is not, technically, an emissions threshold
but rather a leak size that must be detected; nonetheless, for ease we refer to this as the threshold.
There are exceptions to the emissions thresholds shown in Table
II.C-1 whereby a manufacturer can demonstrate that emissions do not
exceed the threshold even when the component or system is non-
functional at which point a functional check would be allowed.
The monitoring requirements described below for gasoline engines
mirror those that are already in place for gasoline engines used in
vehicles under 14,000 pounds. The HD gasoline industry--General Motors
and Ford, as of today \33\--have told us that their preference is to
use essentially the same OBD system on their engines used in both under
and over 14,000 pound vehicles.\34\ In general, we agree with the
[[Page 3224]]
HD gasoline industry on this issue for three reasons:
---------------------------------------------------------------------------
\33\ This is true according to our certification database for
both he 2004 and 2005 model years. Other manufacturers certify
engines that use the Otto cycle, but those engines do not burn
gasoline and instead burn various alternative fuels.
\34\ ``EMA Comments on Proposed HDOBD Requirements for HDGE,''
bullet items 3 and 4; April 28, 2005, Docket ID EPA-HQ-OAR-
2005-0047-0003.
---------------------------------------------------------------------------
The engines used in vehicles above and below 14,000 pounds
are the same which makes it easy for industry to use the same OBD
monitors.
The existing OBD requirements for engines used in vehicles
below 14,000 pounds have proven effective; and,
The industry members have more than 10 years experience
complying with the OBD requirements for engines used in vehicles below
14,000 pounds.
As a result, we are proposing requirements that should allow for
OBD system consistency in vehicles under and over 14,000 pounds rather
than proposing requirements that mirror the proposed HD diesel
requirements discussed in section II.B. Nonetheless, the requirements
proposed below are for engine-based OBD monitors only rather than
monitors for the entire powertrain (which would include the
transmission). We are doing this for the same reasons as done for the
proposed diesel OBD requirements in that certification of gasoline
applications over 14,000 pounds, like their diesel counterparts, is
done on an engine basis and not a vehicle basis.
1. Fuel System Monitoring
a. Background
As with diesel engines, the fuel system of a gasoline engine is an
essential component of the engine's emissions control system. Proper
delivery of fuel is essential to maintain stoichiometric operation and
minimize engine out emissions. Proper stoichiometric control is also
critical to maximize catalyst conversion efficiency and reach low
tailpipe emission levels. As such, thorough monitoring of the fuel
system is an essential element in an OBD system.
For gasoline engines, the fuel system generally includes a fuel
pump, fuel pressure regulator, fuel rail, individual injectors for each
cylinder, and a closed-loop feedback control system using oxygen
sensor(s) or air-fuel ratio (A/F) sensor(s). The feedback sensors are
located in the exhaust system and are used to regulate the fuel
injection quantity to achieve a stoichiometric mixture in the exhaust.
If the sensor indicates a rich (or lean) mixture, the system reduces
(or increases) the amount of fuel being injected by applying a short
term correction to the fuel injection quantity calculated for the
current engine operating condition. To account for aging or
deterioration in the system such as reduced injector flow, more
permanent long term corrections are also learned and applied to the
fuel injection quantity for more precise fueling.
For gasoline engines, fuel system monitoring has been implemented
on light-duty vehicles since the 1996 model year and on heavy-duty
vehicles less than 14,000 pounds and the engines used in those vehicles
since the 2004/2005 model year. For heavy-duty gasoline engines used in
vehicles over 14,000 pounds (many of which are the same engine as is
used in vehicles less than 14,000 pounds), the system components and
control strategies are identical to those used in the light-duty and
under 14,000 pound categories. As such, the monitoring requirements
established for engines used in vehicles less than 14,000 pounds can be
directly applied to engines used in vehicles over 14,000 pounds.
b. Fuel System Monitoring Requirements
We are proposing that the fuel system be continuously monitored for
its ability to maintain engine emissions below the applicable emissions
thresholds. Manufacturers would also be required to verify that the
fuel system is in closed-loop operation--e.g., that it is using the
oxygen sensor for feedback control. The individual components of the
fuel system would also be covered by separate monitoring requirements
for oxygen sensors, misfire (for the fuel injectors), and comprehensive
components (in systems such as those with electronically-controlled
variable speed fuel pumps or electronically-controlled fuel pressure
regulators).
i. Fuel System Performance
We are proposing that the OBD system be required to detect a
malfunction of the fuel delivery system (including feedback control
based on a secondary oxygen sensor) when the fuel delivery system is
unable to maintain the engine's emissions at or below the applicable
emissions thresholds for ``Other monitors'' as shown in Table II.C-1.
ii. Fuel System Feedback Control
If the engine is equipped with adaptive feedback control, we are
proposing that the OBD system be required to detect a malfunction when
the adaptive feedback control has used up all of the adjustment allowed
by the manufacturer. However, if the engine is equipped with feedback
control that is based on a secondary oxygen (or equivalent) sensor, the
OBD system would not be required to detect a malfunction of the fuel
system solely when the feedback control based on that secondary oxygen
sensor has used up all of the adjustment allowed by the manufacturer.
For such systems, the OBD system would be required to meet the fuel
system performance requirements presented above.
Additionally, we are proposing that the OBD system be required to
detect a malfunction whenever the fuel control system fails to enter
closed loop operation within a time interval after engine startup. The
manufacturer would be required to submit data and/or engineering
analyses that support their chosen time interval.
Lastly, manufacturers would be allowed to adjust the malfunction
criteria and/or monitoring conditions to compensate for changes in
altitude, temporary introduction of large amounts of purge vapor, or
for other similar identifiable operating conditions when they occur.
c. Fuel System Monitoring Conditions
We are proposing that the OBD system monitor continuously for
malfunctions of the fuel system.
d. Fuel System MIL Illumination and DTC Storage
We are proposing that a pending DTC be stored immediately upon
detecting a malfunction according to the fuel system monitoring
requirements presented in section II.C.1.b (i.e., rather than waiting
until the end of the drive cycle to store the pending DTC). Once a
pending DTC is stored, the OBD system would be required to illuminate
the MIL immediately and store a MIL-on DTC if a malfunction is again
detected during either of the following two events: (1) The drive cycle
immediately following the drive cycle during which the pending DTC was
stored, regardless of the conditions encountered during the drive
cycle; or, (2) on the next drive cycle during which similar conditions
are encountered to those that occurred when the pending DTC was
stored.\35\
---------------------------------------------------------------------------
\35\ ``Similar conditions,'' as used in conjunction with misfire
and fuel system monitoring, means engine conditions having an engine
speed within 375 rpm, load conditions within 20 percent, and the
same warm up status (i.e., cold or hot) as existing during the
applicable previous problem detection. The Administrator may approve
other definitions of similar conditions based on comparable
timeliness and reliability in detecting similar engine operation.
---------------------------------------------------------------------------
We are also proposing that the pending DTC may be erased at the end
of the next drive cycle in which similar conditions have been
encountered without detecting a malfunction according to the fuel
system monitoring requirements. The pending DTC may also be erased if
similar conditions are not encountered during the 80 drive cycles
immediately after the initial
[[Page 3225]]
detection of a malfunction for which the pending DTC was set.
We are proposing some specific requirements with respect to storage
of freeze frame information associated with fuel system malfunctions.
First, the OBD system must store and erase freeze frame information
either in conjunction with storing and erasing a pending DTC or in
conjunction with storing and erasing a MIL-on DTC. Second, if freeze
frame information is already stored for a malfunction other than an
engine misfire or fuel system malfunction at the time that a fuel
system DTC is stored, the preexisting freeze frame information must be
replaced with freeze frame information regarding the fuel system
malfunction.
The OBD system would also be required to store the engine speed,
load, and warm up status present when the first fuel system malfunction
is detected that resulted in the storage of the pending DTC. The MIL
may be extinguished after three sequential drive cycles in which
similar conditions have been encountered without detecting a
malfunction of the fuel system.
2. Engine Misfire Monitoring
a. Background
Detecting engine misfire on a gasoline spark ignition engine is
important for two reasons: Its impact on the emissions performance of
the engine and its impact on the durability of the catalytic converter.
Engine misfire has two primary causes: Lack of spark and poor fuel
metering (delivery). When misfire occurs, unburned fuel and air are
pumped out of the engine and into the exhaust system and into the
catalyst. This can increase dramatically the operating temperature of
the catalyst where temperatures can soar to above 900 degrees Celsius.
This problem is usually most severe under high load/high speed engine
operating conditions and can cause irreversible damage to the catalyst.
Though the durability of catalysts has been improving, most are unable
to sustain continuous operation at such high temperatures. Engine
misfire also contributes to poor emissions performance, especially when
the misfire occurs during engine warm-up and the catalyst itself has
not yet reached its operating temperature.
b. Engine Misfire Monitoring Requirements
We are proposing that the OBD system detect both engine misfire
capable of causing catalyst damage and engine misfire capable of
causing poor emissions performance. Additionally, the OBD system would
be required to identify the specific cylinder in which misfire is
occurring and/or if there exists a condition in which more than one
cylinder is misfiring; when identifying a multiple cylinder misfire
condition, the OBD system would not be required to identify
individually each of the misfiring cylinders. We are proposing an
exception to this whereby if more than 90 percent of the detected
misfires are occurring in a single cylinder, the manufacturer may elect
to consider it a single cylinder misfire condition rather than a
multiple cylinder misfire condition. However, we are proposing that, if
two or more cylinders individually have more than 10 percent of the
total number of detected misfires, the manufacturer must consider it a
multiple cylinder misfire condition.
i. Engine Misfire Capable of Causing Catalyst Damage
We are proposing that the manufacturer be required to detect the
percentage of misfire--evaluated in 200 revolution increments--for each
engine speed and load condition that would result in a temperature
capable of damaging the catalyst. For every engine speed and load
condition at which this percentage is determined to be less than five
percent, the manufacturer may set the malfunction criteria at five
percent. The manufacturer may use a longer interval than a 200
revolution increment but only for determining, on a given drive cycle,
the first misfire exceedance; upon detecting the first such exceedance,
the 200 revolution increment must be used. The manufacturer may use a
longer initial interval by submitting data and/or engineering analyses
that demonstrate that catalyst damage would not occur due to
unacceptably high catalyst temperatures before the interval has
elapsed.
Further, we are proposing that, for the purpose of establishing the
temperature at which catalyst damage would occur, manufacturers not be
allowed to define the catalyst damaging temperature at a temperature
more severe than what the catalyst system could be operated at for 10
consecutive hours and still meet the applicable standards.
ii. Engine Misfire Causing Poor Emissions Performance
We are proposing that the manufacturer be required to detect the
percentage of misfire--evaluated in 1000 revolution increments--that
would cause emissions to exceed the emissions thresholds for ``Other
monitors'' as shown in Table II.C-1 if that percentage of misfire were
present from the beginning of the test procedure. To establish this
percentage of misfire, the manufacturer would be required to use
misfire events occurring at equally spaced, complete engine cycle
intervals, across randomly selected cylinders throughout each 1000
revolution increment. If this percentage of misfire is determined to be
lower than one percent, the manufacturer may set the malfunction
criteria at one percent. The manufacturer may use a different interval
than a 1000 revolution increment. To do so, the manufacturer would be
required to submit data and/or engineering analyses demonstrating that
the strategy would be equally effective and timely at detecting
misfire. A malfunction must be detected if the percentage of misfire is
exceeded regardless of the pattern of misfire events (e.g., random,
equally spaced, continuous).
c. Engine Misfire Monitoring Conditions
We are proposing that the OBD system monitor continuously to detect
engine misfire under all of the following conditions:
From no later than the end of the second crankshaft
revolution after engine start;
During the rise time and settling time as the engine
reaches the desired idle speed immediately following engine start-up
(i.e., ``flare-up'' and ``flare-down''); and,
Under all positive torque conditions except within the
engine operating region bound by lines connecting the following three
points: An engine speed of 3000 rpm with the engine load at the
positive torque line (i.e., engine load with the transmission in
neutral), an engine speed at the redline rpm with the engine load at
the positive torque line, and an engine speed at the redline rpm with
an engine load at which intake manifold vacuum is four inches of
mercury lower than that at the positive torque line (this would be an
engine load somewhat greater than the engine load at the positive
torque line).\36\
---------------------------------------------------------------------------
\36\ ``Redline engine speed'' is actually defined by the
manufacturer as either the recommended maximum engine speed as
normally displayed on instrument panel tachometers or the engine
speed at which fuel shutoff occurs.
---------------------------------------------------------------------------
If a monitoring system cannot detect all misfire patterns under the
required engine speed and load conditions, the manufacturer may request
approval of the system nonetheless. In evaluating the manufacturer's
request, the Administrator would consider:
The magnitude of the region(s) in which misfire detection
is limited;
The degree to which misfire detection is limited in those
region(s)
[[Page 3226]]
(i.e., the probability of detection of misfire events);
The frequency with which said region(s) are expected to be
encountered in-use;
The type of misfire patterns for which misfire detection
is troublesome; and,
Demonstration that the monitoring technology being used is
not inherently incapable of detecting misfire under the required
conditions (i.e., compliance can be achieved by other manufacturers on
their engines).
The Administrator's evaluation would be based on the following
misfire patterns:
Equally spaced misfire occurring on randomly selected
cylinders;
Single cylinder continuous misfire; and,
Paired cylinder (cylinders firing at the same crank angle)
continuous misfire.
Further, a manufacturer may use a monitoring system that has
reduced misfire detection capability during the portion of the first
1000 revolutions after engine start during which a cold start emission
reduction strategy is active that reduces engine torque (e.g., spark
retard strategies). To do so, the manufacturer would be required to
submit data and/or engineering analyses demonstrating that the
probability of detection is greater than or equal to 75 percent during
the worst case condition (i.e., lowest generated torque) for a vehicle
operated continuously at idle (park/neutral idle) on a cold start
between 50 and 86 degrees Fahrenheit and that the technology cannot
reliably detect a higher percentage of the misfire events during these
conditions.
A manufacturer may disable misfire monitoring or use an alternative
malfunction criterion when misfire cannot be distinguished from other
effects. To do so, the manufacturer would be required to submit data
and/or engineering analyses demonstrating that the disablement interval
or period of use of an alternative malfunction criterion is limited
only to that necessary for avoiding a false detection (errors of
commission). Such disablements would be allowed for conditions
involving:
Rough road;
Fuel cut;
Gear changes for manual transmission vehicles;
Traction control or other vehicle stability control
activation such as anti-lock braking or other engine torque
modifications to enhance vehicle stability;
Off-board control or intrusive activation of vehicle
components or diagnostics during service or assembly plant testing;
Portions of intrusive evaporative system or EGR
diagnostics that can significantly affect engine stability (i.e., while
the purge valve is open during the vacuum pull-down of a evaporative
system leak check but not while the purge valve is closed and the
evaporative system is sealed or while an EGR diagnostic causes the EGR
valve to be intrusively cycled on and off during positive torque
conditions); or,
Engine speed, load, or torque transients due to throttle
movements more rapid than occurs over the FTP cycle for the worst case
engine within each engine family.
Additionally, the manufacturer may disable misfire monitoring when
the fuel level is 15 percent or less of the nominal capacity of the
fuel tank, when PTO units are active, or while engine coolant
temperature is below 20 degrees Fahrenheit. For the latter case, the
manufacturer may continue the misfire monitoring disablement until
engine coolant temperature exceeds 70 degrees Fahrenheit provided the
manufacturer can demonstrate that it is necessary.
In general, the Administrator would not approve misfire monitoring
disablement for conditions involving normal air conditioning compressor
cycling from on-to-off or off-to-on, automatic transmission gear shifts
(except for shifts occurring during wide open throttle operation),
transitions from idle to off-idle, normal engine speed or load changes
that occur during the engine speed rise time and settling time (i.e.,
``flare-up'' and ``flare-down'') immediately after engine starting
without any vehicle operator-induced actions (e.g., throttle stabs), or
excess acceleration (except for acceleration rates that exceed the
maximum acceleration rate obtainable at wide open throttle while the
vehicle is in gear due to abnormal conditions such as slipping of a
clutch).
Further, the manufacturer may request approval of other misfire
monitoring disablements or use of alternative malfunction criteria for
any other condition. The Administrator would consider such requests on
a case by case basis and will consider whether or not the manufacturer
has demonstrated that the request is based on an unusual or unforeseen
circumstance and that it is applying the best available computer and
monitoring technology.
For engines with more than eight cylinders that cannot meet the
continuous monitoring and detection requirements listed above, a
manufacturer may use alternative misfire monitoring conditions. Any
manufacturer wishing to use alternative misfire monitoring conditions
must submit data and/or an engineering evaluation that demonstrate that
misfire detection throughout the required operating region cannot be
achieved when using proven monitoring technology (i.e., a technology
that provides for compliance with these requirements on other engines)
and provided misfire is detected to the fullest extent permitted by the
technology. However, the misfire detection system would still be
required to monitor during all positive torque operating conditions
encountered during an FTP transient cycle.
d. Engine Misfire MIL Illumination and DTC Storage
Manufacturers may store a general misfire DTC instead of a cylinder
specific DTC under certain operating conditions. Do so shall depend on
the manufacturer submitting data and/or an engineering evaluation that
demonstrate that the specific misfiring cylinder cannot be reliably
identified when the certain operating conditions occur.
i. Engine Misfire Capable of Causing Catalyst Damage
We are proposing that a pending DTC shall be stored immediately if,
during a single drive cycle, the percentage of misfire determined by
the manufacturer as being capable of causing catalyst damage is
exceeded three times when operating in the positive torque region
encountered during an FTP transient cycle or is exceeded on a single
occasion when operating at any other engine speed and load condition in
the positive torque region defined above. Immediately after a pending
DTC is stored, the MIL shall blink once per second at all times while
misfire is occurring during the drive cycle (i.e., the MIL may be
extinguished during those times when misfire is not occurring during
the drive cycle). If, at the time such a catalyst damaging engine
misfire is occurring, the MIL is already illuminated for a malfunction
other than engine misfire, the MIL shall blink similarly while the
engine misfire is occurring and, if the misfire ceases, the MIL shall
stop blinking but shall remain illuminated as commanded by the other
malfunction.
If a pending DTC is stored as described above, the OBD system shall
immediately store a MIL-on DTC if the percentage of misfire determined
by the manufacturer as being capable of causing catalyst damage is
again exceeded one or more times during either: (a) the drive cycle
immediately
[[Page 3227]]
following the storage of the pending DTC, regardless of the conditions
encountered during the drive cycle; or, (b) on the next drive cycle in
which similar conditions are encountered to those that existed when the
pending DTC was stored.
If, during a previous drive cycle, a pending DTC has been stored
associated with detection of an engine misfire capable of causing poor
emissions performance, the OBD system shall immediately store a MIL-on
DTC if the percentage of misfire determined by the manufacturer as
capable of causing catalyst damage is exceeded, regardless of the
conditions encountered.
Upon storage of a MIL-on DTC associated with engine misfire capable
of causing catalyst damage, the MIL shall blink as described above
while the engine misfire is occurring and then shall remain
continuously illuminated if the engine misfire ceases. This MIL
illumination logic shall continue until the requirements for
extinguishing the MIL are met, as described below.
If the engine misfire is not again detected by the end of the next
drive cycle in which similar conditions are encountered to those that
existed when the pending DTC was stored then the pending DTC shall be
erased. The pending DTC may also be erased if similar conditions are
not encountered during the 80 drive cycles subsequent to the initial
malfunction detection.
We are also proposing that engines with fuel shutoff and default
fuel control--that are used to prevent catalyst damage should engine
misfire capable of causing catalyst damage be detected--shall have some
exemptions from these MIL illumination requirements. Most notably, the
MIL is not required to blink while the catalyst damaging misfire is
occurring. Instead, the MIL may simply illuminate in a steady fashion
while the misfire is occurring provided that the fuel shutoff and
default fuel control are activated as soon as the misfire is detected.
Fuel shutoff and default fuel control may be deactivated only to permit
fueling outside of the misfire range. Manufacturers may also
periodically, but not more than once every 30 seconds, deactivate fuel
shutoff and default fuel control to determine if the catalyst damaging
misfire is still occurring. Normal fueling and fuel control may be
resumed if the catalyst damaging misfire is no longer being detected.
Manufacturers may also use a MIL illumination strategy that
continuously illuminates the MIL in lieu of blinking the MIL during
extreme misfire conditions capable of causing catalyst damage (i.e.,
misfire capable of causing catalyst damage that is occurring at all
engine speeds and loads). Manufacturers would be allowed to use such a
strategy only when catalyst damaging misfire levels cannot be avoided
during reasonable driving conditions and the manufacturer can
demonstrate that the strategy will encourage operation of the vehicle
in conditions that will minimize catalyst damage (e.g., at low engine
speeds and loads).
ii. Engine Misfire Causing Poor Emissions Performance
We are proposing that, for a misfire detected within the first 1000
revolutions after engine start during which misfire detection is
active, a pending DTC shall be stored after the first exceedance of the
percentage of misfire determined by the manufacturer as capable of
causing poor emissions performance. If a pending DTC is stored, the OBD
system shall illuminate the MIL and store a MIL-on DTC within 10
seconds if an exceedance of the percentage of misfire is again detected
in the first 1000 revolutions during any subsequent drive cycle,
regardless of the conditions encountered during the driving cycle. The
pending DTC shall be erased at the end of the next drive cycle in which
similar conditions are encountered to those that existed when the
pending DTC was stored provided the specified percentage of misfire is
not again detected. The pending DTC may also be erased if similar
conditions are not encountered during the 80 drive cycles subsequent to
the initial malfunction detection.
For a misfire detected after the first 1000 revolutions following
engine start, a pending DTC shall be stored no later than after the
fourth exceedance--during a single drive cycle--of the percentage of
misfire determined by the manufacturer as being capable of causing poor
emissions performance. If a pending DTC is stored, the OBD system shall
illuminate the MIL and store a MIL-on DTC within 10 seconds if an
exceedance of the percentage of misfire is again detected four times
during: (a) the drive cycle immediately following the storage of the
pending DTC, regardless of the conditions encountered during the drive
cycle; or, (b) on the next drive cycle in which similar conditions are
encountered to those that existed when the pending DTC was stored. The
pending DTC shall be erased at the end of the next drive cycle in which
similar conditions are encountered to those that existed when the
pending DTC was stored provided the specified percentage of misfire is
not again detected. The pending DTC may also be erased if similar
conditions are not encountered during the 80 drive cycles subsequent to
the initial malfunction detection.
We are proposing some specific items with respect to freeze frame
storage associated with engine misfire. The OBD system shall store and
erase freeze frame conditions either in conjunction with storing and
erasing a pending DTC or in conjunction with storing a MIL-on DTC and
erasing a MIL-on DTC. In addition to those proposed requirements
discussed in section II.A.2, we are proposing that, if freeze frame
conditions are stored for a malfunction other than a misfire
malfunction when a DTC is stored, the previously stored freeze frame
information shall be replaced with freeze frame information regarding
the misfire malfunction (i.e., the misfire's freeze frame information
should take precedence over freeze frames for other malfunctions).
Further, we are proposing that, upon detection of misfire, the OBD
system store the following engine conditions: engine speed, load, and
warm up status of the first misfire event that resulted in the storage
of the pending DTC.
Lastly, we are proposing that the MIL may be extinguished after
three sequential driving cycles in which similar conditions have been
encountered without an exceedance of the specified percentage of
misfire.
3. Exhaust Gas Recirculation (EGR) Monitoring
a. Background
EGR works to reduce NOX emissions the same way in
gasoline engines as described earlier for diesel engines. First, the
recirculated exhaust gases dilute the intake air--i.e., oxygen in the
fresh air is displaced with relatively non-reactive exhaust gases--
which, in turn, results in less oxygen to form NOX. Second,
EGR absorbs heat from the combustion process which reduces combustion
chamber temperatures which, in turn, reduces NOX formation.
The amount of heat absorbed from the combustion process is a function
of EGR flow rate and recirculated gas temperature, both of which are
controlled to minimize NOX emissions. EGR systems can
involve many components to ensure accurate control of EGR flow,
including valves, valve position sensors, and actuators.
b. EGR System Monitoring Requirements
We are proposing that the OBD system monitor the EGR system on
engines so equipped for low and high
[[Page 3228]]
flow rate malfunctions. The individual electronic components (e.g.,
actuators, valves, sensors) that are used in the EGR system must be
monitored in accordance with the comprehensive component requirements
in section II.D.4.
i. EGR Low Flow Malfunctions
We are proposing that the OBD system detect a malfunction prior to
a decrease from the manufacturer's specified EGR flow rate that would
cause an engine's emissions to exceed the emissions thresholds for
``other monitors'' as shown in Table II.C-1. For engines in which no
failure or deterioration of the EGR system that causes a decrease in
flow could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system would have to detect a malfunction
when the system has reached its control limits such that it cannot
increase EGR flow to achieve the commanded flow rate.
ii. EGR High Flow Malfunctions
We are proposing that the OBD system detect a malfunction of the
EGR system, including a leaking EGR valve--i.e., exhaust gas flowing
through the valve when the valve is commanded closed--prior to an
increase from the manufacturer's specified EGR flow rate that would
cause an engine's emissions to exceed the emissions thresholds for
``other monitors'' as shown in Table II.C-1. For engines in which no
failure or deterioration of the EGR system that causes an increase in
flow could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system would have to detect a malfunction
when the system has reached its control limits such that it cannot
reduce EGR flow to achieve the commanded flow rate.
c. EGR System Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for EGR system malfunctions such that the minimum
performance ratio requirements discussed in section II.E would be met.
For purposes of tracking and reporting as required in section II.E, all
monitors used to detect EGR low flow and high flow malfunctions must be
tracked separately but reported as a single set of values as specified
in section II.E.\37\
---------------------------------------------------------------------------
\37\ For specific components or systems that have multiple
monitors that are required to be reported (e.g., exhaust gas sensor
bank 1 may have multiple monitors for sensor response or other
sensor characteristics), the OBD system must separately track
numerators and denominators for each of the specific monitors and
report only the corresponding numerator and denominator for the
specific monitor that has the lowest numerical ratio. If two or more
specific monitors have identical ratios, the corresponding numerator
and denominator for the specific monitor that has the highest
denominator shall be reported for the specific component.
---------------------------------------------------------------------------
Manufacturers may temporarily disable the EGR system monitor under
conditions when monitoring may not be reliable (e.g., when freezing may
affect performance of the system). Such temporary disablement would be
allowed provided the manufacturer has submitted data and/or an
engineering evaluation that demonstrate that the EGR monitor cannot be
done reliably when these specific conditions exist.
d. EGR System MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2.
4. Cold Start Emission Reduction Strategy Monitoring
a. Background
The largest portion of exhaust emissions from gasoline engines is
generated during the brief period following startup before the engine
and catalyst have warmed up to their normal operating temperatures. To
meet increasingly stringent emissions standards, manufacturers are
developing hardware and associated control strategies to reduce these
``cold start'' emissions. Most efforts center on reducing catalyst
warm-up time.
A cold catalyst is heated mainly by two mechanisms: heat
transferred from the exhaust gases to the catalyst; and, heat generated
in the catalyst as a result of the exothermic catalytic reactions. Most
manufacturers use substantial spark retard and/or increased idle speed
following a cold engine start, both of which maximize the heat
available in the exhaust gases which, in turn, increases the heat
transfer to the catalyst. Vehicle drivability and engine idle quality
concerns tend to limit the amount of spark retard and/or increased idle
speed that a manufacturer can use to accelerate catalyst warm up. These
strategies or, more correctly, the systems used to employ these
strategies--the ignition system for spark retard and the idle control
system for control of engine speed--are normally monitored only after
engine warm-up. Therefore, any malfunctions that might occur during the
cold start event may not be detected by the OBD system. This could have
significant emissions consequences due to the unknown loss of emissions
control during the time following engine startup.
This concern is exacerbated by the high cost of precious metals--
the platinum group metals (PGM) platinum, palladium, and rhodium--which
motivates industry to minimize their use in catalysts. To compensate
for the resultant reduction in overall catalyst performance,
manufacturers will likely use increasingly more aggressive cold start
emission reduction strategies in an attempt to further reduce cold
start emissions. These strategies must be successful--and be properly
monitored--to meet the more stringent 2008 emissions standards and to
maintain low emissions in-use.
b. Cold Start Emission Reduction Strategy Monitoring Requirements
We are proposing that, if an engine incorporates an engine control
strategy specifically to reduce cold start emissions, the OBD system
must monitor the key components (e.g., idle air control valve), other
than the secondary air system, while the control strategy is active to
ensure that the control strategy is operating properly. Secondary air
systems would have to be monitored separately as discussed in section
II.C.5.
The OBD system would be required to detect a malfunction prior to
any failure or deterioration of the individual components associated
with the cold start emissions reduction control strategy that would
cause an engine's emissions to exceed the emissions thresholds for
``other monitors'' as shown in Table II.C-1. For components where no
failure or deterioration of the component used by the cold start
emission reduction strategy could result in an engine's emissions
exceeding the applicable emissions thresholds, the individual
components would have to be monitored for proper functional response as
described in section II.D.4 while the control strategy is active.
Manufacturers would be required to establish the appropriate
malfunction criteria based on data from one or more representative
engine(s). Further, manufacturers would be required to provide an
engineering evaluation for establishing the malfunction criteria for
the remainder of the manufacturer's product line. An annual evaluation
of these criteria by the Administrator may not be necessary provided
the manufacturer can demonstrate that any technological changes from
one year to the next do not affect the previously approved malfunction
criteria.
c. Cold Start Emission Reduction Strategy Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for
[[Page 3229]]
malfunctions of the cold start emissions reduction strategy such that
the minimum performance ratio requirements discussed in section II.E
would be met.
d. Cold Start Emission Reduction Strategy MIL Illumination and DTC
Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2.
5. Secondary Air System Monitoring
a. Background
Secondary air systems--expected to be used on gasoline engines
only--are used to reduce cold start emissions of hydrocarbons and
carbon monoxide. Many of today's engines operate near stoichiometry
after a cold engine start. However, the future more stringent emission
standards may require the addition of a secondary air system in
combination with a richer than stoichiometric cold start mixture. Such
an approach could quickly warm up the catalyst for improved cold start
emissions performance.
Secondary air systems typically consist of an electric air pump,
various hoses, and check valves to deliver outside air to the exhaust
system upstream of the catalytic converter(s). This system usually
operates only after a cold engine start and usually for only a brief
period of time. When the electric air pump is operating, fresh air is
delivered into the exhaust where it mixes with and ignites any unburned
fuel. This serves to warm up the catalyst far more rapidly than would
otherwise occur. Any problems that might occur in the field--corroded
check valves, damaged tubing and hoses, malfunctioning air switching
valves--could cause cold start emissions performance to suffer.
Therefore, monitoring is needed given the importance of a properly
functioning secondary air system to emissions performance.
b. Secondary Air System Monitoring Requirements
We are proposing that the OBD system on engines equipped with any
form of secondary air delivery system be required to monitor the proper
functioning of the secondary air delivery system, including all air
switching valve(s). The individual electronic components (e.g.,
actuators, valves, sensors) in the secondary air system would have to
be monitored in accordance with the comprehensive component
requirements discussed in section II.D.4.
i. Secondary Air System Low Flow Malfunctions
We are proposing that the OBD system detect a secondary air system
malfunction prior to a decrease from the manufacturer's specified air
flow during normal operation that would cause an engine's emissions to
exceed the emissions thresholds for ``other monitors'' as shown in
Table II.C-1.\38\ For engines in which no deterioration or failure of
the secondary air system would result in an engine's emissions
exceeding any of the applicable emissions thresholds, the OBD system
would have to detect a malfunction when no detectable amount of air
flow is delivered during normal operation of the secondary air system.
---------------------------------------------------------------------------
\38\ For purposes of secondary air system malfunctions, ``air
flow'' is defined as the air flow delivered by the secondary air
system to the exhaust system. For engines using secondary air
systems with multiple air flow paths/distribution points, the air
flow to each bank (i.e., a group of cylinders that share a common
exhaust manifold, catalyst, and control sensor) must be monitored in
accordance with these malfunction criteria. Also, ``normal
operation'' is defined as the condition where the secondary air
system is activated during catalyst and/or engine warm-up following
engine start. ``Normal operation'' does not include the condition
where the secondary air system is intrusively turned on solely for
the purpose of monitoring.
---------------------------------------------------------------------------
ii. Secondary Air System High Flow Malfunctions
We are proposing that the OBD system detect a secondary air system
malfunction prior to an increase from the manufacturer's specified air
flow during normal operation that would cause an engine's emissions to
exceed the emissions thresholds for ``other monitors'' as shown in
Table II.C-1.\39\ For engines in which no deterioration or failure of
the secondary air system would result in an engine's emissions
exceeding any of the applicable emissions thresholds, the OBD system
would have to detect a malfunction when no detectable amount of air
flow is delivered during normal operation of the secondary air system.
---------------------------------------------------------------------------
\39\ Ibid.
---------------------------------------------------------------------------
c. Secondary Air System Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for malfunctions of the secondary air system such that the
minimum performance ratio requirements discussed in section II.E would
be met. For purposes of tracking and reporting as required in section
II.E, all monitors used to detect malfunctions of the secondary air
system during its normal operation must be tracked separately but
reported as a single set of values as specified in section II.E
d. Secondary Air System MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2.
6. Catalytic Converter Monitoring
a. Background
Three-way catalysts are one of the most important emission-control
components on gasoline engines. They consist of ceramic or metal
substrates coated with the one or more of the platinum group metals
(PGM) platinum, palladium, and rhodium. These PGMs are dispersed within
an alumina washcoat containing ceria, and the substrates are mounted in
a stainless steel container in the vehicle exhaust system. Three-way
catalysts are capable of oxidizing HC emissions, oxidizing CO
emissions, and reducing NOX emissions, hence the term three-
way.
While continuous improvements to catalysts have increased their
durability, their performance still deteriorates, especially when
subjected to very high temperatures. Such high temperatures can be
caused by, among other factors, engine misfire which results in
unburned fuel and air entering and igniting in the catalyst. Exposure
to such high temperatures will result in reduced catalyst conversion
efficiency. Catalyst efficiency can also deteriorate via poisoning if
exposed to lead, phosphorus, or high sulfur levels. Catalysts can also
fail by mechanical means such as excessive vibration. Given its
importance to emissions control and the many factors that can reduce
its effectiveness, the catalyst is one of the most important components
to be monitored.
b. Catalytic Converter Monitoring Requirements
We are proposing that the OBD system monitor the catalyst system
for proper conversion capability. Specifically, the OBD system would be
required to detect a catalyst system malfunction when the catalyst
system's conversion capability decreases to the point that any of the
following occurs:
NMHC and/or NOX emissions exceed the emissions
thresholds for the ``catalytic converter system'' as shown in Table
II.C-1.
For purposes of determining the catalyst system malfunction
criteria the manufacturer would be required to use a catalyst system
deteriorated to the malfunction criteria using methods established by
the manufacturer to
[[Page 3230]]
represent real world catalyst deterioration under normal and
malfunctioning operating conditions. The malfunction criteria must be
established by using a catalyst system with all monitored and
unmonitored catalysts simultaneously deteriorated to the malfunction
criteria.\40\ For engines using fuel shutoff to prevent over-fueling
during misfire conditions (see section II.C.2), the malfunction
criteria could be established using a catalyst system with all
monitored catalysts simultaneously deteriorated to the malfunction
criteria and all unmonitored catalysts deteriorated to the end of the
engine's useful life.
---------------------------------------------------------------------------
\40\ The unmonitored portion of the catalyst system would be
that portion downstream of the sensor(s) used for catalyst
monitoring.
---------------------------------------------------------------------------
c. Catalytic Converter Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for malfunctions of the catalytic converter system such that
the minimum performance ratio requirements discussed in section II.E
would be met. For purposes of tracking and reporting as required in
section II.E, all monitors used to detect malfunctions of the catalytic
converter system during its normal operation must be tracked separately
but reported as a single set of values as specified in section II.E.
d. Catalytic Converter MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2. Note that the monitoring
method for the catalyst(s) would have to be capable of detecting all
instances, except diagnostic self-clearing, when a catalyst DTC has
been cleared but the catalyst has not been replaced (e.g., catalyst
over temperature histogram approaches are not acceptable).
7. Evaporative Emission Control System Monitoring
a. Background
The evaporative emission control system controls HC emissions that
would otherwise evaporate from the vehicle's fuel tank and fuel lines.
Should any leak develop in the evaporative emission control system--
e.g., a disconnected hose--the HC emissions can be quite high and well
over the evaporative emissions standards. Additionally, evaporative
purge system defects--e.g., deteriorated vacuum lines, damaged
canisters, non-functioning purge control valves--may occur which could
also result in very high evaporative emissions.
b. Evaporative System Monitoring Requirements
We are proposing that the OBD system verify purge flow from the
evaporative system and detect any vapor leaks from the complete
evaporative system, excluding the tubing and connections between the
purge valve and the intake manifold. Individual components of the
evaporative system (e.g. valves, sensors) must be monitored in
accordance with the comprehensive components requirements discussed in
section II.D.4.
The OBD system would be required to detect an evaporative system
malfunction when any of the following conditions exist:
No purge flow from the evaporative system to the engine
can be detected by the OBD system (i.e., the ``purge flow''
requirement); or
For the 2010 and later model years, the complete
evaporative system contains a leak or leaks that cumulatively are
greater than or equal to a leak caused by a 0.150 inch diameter orifice
(i.e., the ``system leak'' requirement).\41\
---------------------------------------------------------------------------
\41\ In their HDOBD regulation, 13 CCR 1971.1, CARB defines
``orifice'' as an O'Keefe Controls Co. precision metal ``Type B''
orifice with NPT connections with a diameter of the specified
dimension (e.g., part number B-31-SS for a stainless steel 0.031
inch diameter orifice).
---------------------------------------------------------------------------
If the most reliable monitoring method available cannot reliably
detect a system leak as specified above, a manufacturer may design
their system to detect a larger leak. The manufacturer would be
required to provide data and/or engineering analyses that demonstrate
the inability of the monitor to reliably detect the required leak and
their justification for detecting at their proposed orifice size.
Further, if the manufacturer can demonstrate that leaks of the required
size cannot cause evaporative or running loss emissions to exceed 1.5
times the applicable evaporative emissions standards, the Administrator
would revise upward the required leak size to the size demonstrated by
the manufacturer that would result in emissions exceeding 1.5 times the
standards.
c. Evaporative System Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for both purge flow and system leak malfunctions such that
the minimum performance ratio requirements discussed in section II.E
would be met. For purposes of tracking and reporting as required in
section II.E, all monitors used to detect system leak malfunctions must
be tracked separately but reported as a single set of values as
specified in section II.E.
Manufacturers may disable or abort an evaporative emission control
system monitor when the fuel tank level is over 85 percent of nominal
tank capacity or during a refueling event. Manufacturers may design
their evaporative emission control system monitor such that it executes
only during drive cycles determined by the manufacturer to be cold
starts if such a condition is needed to ensure reliable monitoring. The
manufacturer would have to provide data and/or an engineering
evaluation demonstrating that a reliable check can only be made on
drive cycles when the cold start criteria are satisfied. However, the
manufacturer may not determine a cold start solely on the basis that
ambient temperature is higher than engine coolant temperature at engine
start. Lastly, manufacturers would be allowed to disable temporarily
the evaporative purge system to perform an evaporative system leak
check.
d. Evaporative System MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2, with an exception for leaks
associated with the fuel filler cap. If the OBD system is capable of
discerning that a system leak is being caused by a missing or
improperly secured fuel filler cap, the manufacturer is not required to
illuminate the MIL or store a DTC provided the vehicle is equipped with
an alternative indicator for notifying the vehicle operator of the fuel
filler cap ``malfunction.'' The alternative indicator would have to be
of sufficient illumination and location to be readily visible to the
vehicle operator under all lighting conditions. However, if the vehicle
is not equipped with an alternative indicator and, instead, the MIL is
illuminated to inform the operator of the ``malfunction,'' the MIL may
be extinguished and the corresponding DTC(s) erased once the OBD system
has verified that the fuel filler cap has been securely fastened and
the MIL has not been commanded ON for any other type of malfunction.
The Administrator may approve other strategies provided the
manufacturer was able to demonstrate that the vehicle operator would be
promptly notified of the missing or improperly secured fuel filler cap
and that the notification would reasonably result in corrective action
being undertaken.
[[Page 3231]]
8. Exhaust Gas Sensor Monitoring
a. Background
Exhaust gas sensors (e.g., oxygen sensors, air-fuel ratio (A/F)
sensors) are a critical element of the emissions control system on
gasoline engines. In addition to maintaining a stoichiometric air-fuel
mixture and, thus, helping to achieve the lowest possible emissions,
these sensors are also used for enhancing the performance of several
emission control technologies--e.g., catalysts, EGR systems). Many
modern vehicles control the fuel supply with an oxygen sensor feedback
system to maintain stoichiometry. Oxygen sensors are located typically
in the exhaust system upstream and downstream of the catalytic
converters. The front, or upstream, oxygen sensor is used generally for
fuel control. The rear, or downstream, oxygen sensor is used generally
for adjusting the front oxygen sensor signal as it drifts slightly with
age related deterioration--often referred to as fuel trimming--and for
onboard monitoring the catalyst system. Many vehicles use A/F sensors
in lieu of the more conventional oxygen sensors since A/F sensors
provide a precise reading of the actual air-fuel ratio.
We expect that heavy-duty gasoline manufacturers will use both of
these types of sensors to optimize their emissions control strategies
and to satisfy many of the proposed heavy-duty OBD monitoring
requirements--fuel system monitoring, catalyst monitoring, EGR system
monitoring. Since exhaust gas sensors can be a critical component of an
engine's fuel and emissions control system, their proper performance
needs to be assured to maintain low emissions. Thus, any malfunction
that adversely affects the performance of any of these exhaust gas
sensors should be detected by the OBD system.
b. Exhaust Gas Sensor Monitoring Requirements
We are proposing that the OBD system monitor the output signal,
response rate, and any other parameter that could affect emissions of
all primary (i.e., fuel control) exhaust gas sensors for malfunction.
Both the lean to rich and rich to lean response rates must be
monitored. In addition, we are proposing that the OBD system monitor
all secondary exhaust gas sensors (i.e., those used for fuel trimming
or as a monitoring device for another system) for proper output signal,
activity, and response rate. For engines equipped with heated exhaust
gas sensors, the OBD system would be required to monitor the sensor
heater for proper performance.
i. Primary Exhaust Gas Sensors
We are proposing that the OBD system detect a malfunction prior to
any failure or deterioration of the exhaust gas sensor output voltage,
resistance, impedance, current, response rate, amplitude, offset, or
other characteristic(s) (including drift or bias corrected for by
secondary sensors) that would cause an engine's emissions to exceed the
emissions thresholds for ``other monitors'' as shown in Table II.C-1.
The OBD system would also be required to detect the following exhaust
gas sensor malfunctions:
Those caused by either a lack of circuit continuity or
out-of-range values.
Those where a sensor failure or deterioration causes the
fuel system to stop using that sensor as a feedback input (e.g., causes
default or open-loop operation).
Those where the sensor output voltage, resistance,
impedance, current, amplitude, activity, or other characteristics are
no longer sufficient for use as an OBD system monitoring device (e.g.,
for catalyst monitoring).
ii. Secondary Exhaust Gas Sensors
We are proposing that the OBD system detect a malfunction prior to
any failure or deterioration of the exhaust gas sensor voltage,
resistance, impedance, current, response rate, amplitude, offset, or
other characteristic(s) that would cause an engine's emissions to
exceed the emissions thresholds for ``other monitors'' as shown in
Table II.C-1. The OBD system would also be required to detect the
following exhaust gas sensor malfunctions:
Those caused by either a lack of circuit continuity or
out-of-range values.
Those where a sensor failure or deterioration causes the
fuel system to stop using that sensor as a feedback input (e.g., causes
default or open-loop operation).
Those where the sensor output voltage, resistance,
impedance, current, amplitude, activity, or other characteristics are
no longer sufficient for use as an OBD system monitoring device (e.g.,
for catalyst monitoring).
iii. Exhaust Gas Sensor Heaters
We are proposing that the OBD system detect a malfunction of the
sensor heater performance when the current or voltage drop in the
heater circuit is no longer within the manufacturer's specified limits
for normal operation (i.e., within the criteria required by the
component vendor for heater circuit performance at high mileage). The
manufacturer may use other malfunction criteria for heater performance
malfunctions. To do so, the manufacturer would be required to submit
data and/or engineering analyses that demonstrate that the monitoring
reliability and timeliness would be equivalent to the criteria stated
here.
In addition, the OBD system would be required to detect
malfunctions of the heater circuit including open or short circuits
that conflict with the commanded state of the heater (e.g., shorted to
12 Volts when commanded to 0 Volts (ground)).
c. Exhaust Gas Sensor Monitoring Conditions
i. Primary Exhaust Gas Sensors
We are proposing that manufacturers define the monitoring
conditions for primary exhaust gas sensor malfunctions causing
exceedance of the applicable thresholds and/or inability to perform as
an OBD monitoring device such that the minimum performance ratio
requirements discussed in section II.E would be met. For purposes of
tracking and reporting as required in section II.E, all such monitors
must be tracked separately but reported as a single set of values as
specified in section II.E.
Monitoring for primary exhaust gas sensor malfunctions related to
circuit continuity, out-of-range, and open-loop operation must be done
continuously with the exception that manufacturers may disable
continuous exhaust gas sensor monitoring when an exhaust gas sensor
malfunction cannot be distinguished from other effects. As an example,
a manufacturer may disable monitoring for out-of-range on the low side
during conditions where fuel has been cut (i.e., shut off temporarily).
To do so, the manufacturer would have to submit data and/or engineering
analyses that demonstrate that a properly functioning sensor cannot be
distinguished from a malfunctioning sensor and that the disablement
interval is limited only to that necessary for avoiding a false
detection.
ii. Secondary Exhaust Gas Sensors
We are proposing that manufacturers define the monitoring
conditions for secondary exhaust gas sensor malfunctions causing
exceedance of the applicable emissions thresholds, lack of circuit
continuity, and/or inability to perform as an OBD monitoring device
such that the minimum performance ratio requirements discussed in
section II.E would be met.
Monitoring for secondary exhaust gas sensor malfunctions related to
out-of-
[[Page 3232]]
range and open loop operation must be done continuously with the
exception that manufacturers may disable continuous exhaust gas sensor
monitoring when an exhaust gas sensor malfunction cannot be
distinguished from other effects. As an example, a manufacturer may
disable monitoring for out-of-range on the low side during conditions
where fuel has been cut (i.e., shut off temporarily). To do so, the
manufacturer would have to submit data and/or engineering analyses that
demonstrate that a properly functioning sensor cannot be distinguished
from a malfunctioning sensor and that the disablement interval is
limited only to that necessary for avoiding a false detection.
iii. Sensor Heaters
We are proposing that manufacturers define monitoring conditions
for sensor heater performance malfunctions such that the minimum
performance ratio requirements discussed in section II.E would be met.
Monitoring for sensor heater circuit malfunctions must be done
continuously.
d. Exhaust Gas Sensor MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2.
D. Monitoring Requirements and Timelines for Other Diesel and Gasoline
Systems
1. Variable Valve Timing and/or Control (VVT) System Monitoring
a. Background
Variable valve timing (VVT) and/or control systems are used
primarily to optimize engine performance and have many advantages over
conventional valve control. Instead of opening and closing the valves
by fixed amounts and at fixed times, VVT controls can vary the timing
of valve opening/closing and vary the effective size of the valve
opening itself (in some systems) depending on the driving conditions
(e.g., high engine speed and load). This feature permits a better
compromise between performance, driveability, and emissions than
conventional systems. With more stringent NOX emission
standards being phased in, more vehicles are anticipated to use VVT. By
doing so, some exhaust gas can be retained in the combustion chamber
thereby reducing peak combustion temperatures and, hence,
NOX emissions (known as ``internal EGR'').
b. VVT and/or Control System Monitoring Requirements
We are proposing that the OBD system monitor the VVT system on
engines so equipped for target error and slow response malfunctions.
The individual electronic components (e.g., actuators, valves, sensors)
that are used in the VVT system must be monitored in accordance with
the comprehensive components requirements in section II.D.4.
i. VVT Target Error Malfunctions
We are proposing that the OBD system detect a malfunction prior to
any failure or deterioration in the capability of the VVT system to
achieve the commanded valve timing and/or control within a crank angle
and/or lift tolerance that would cause an engine's emissions to exceed
the emissions thresholds for ``other monitors'' as shown in Table II.B-
1 for diesel engines or Table II.C-1 for gasoline engines. For engines
in which no failure or deterioration of the VVT system could result in
an engine's emissions exceeding the applicable emissions thresholds,
the OBD system would have to detect a malfunction of the VVT system
when proper functional response of the system to computer commands does
not occur.
ii. VVT Slow Response Malfunctions
We are proposing that the OBD system detect a malfunction prior to
any failure or deterioration in the capability of the VVT system to
achieve the commanded valve timing and/or control within a
manufacturer-specified time that would cause an engine's emissions to
exceed the emissions thresholds for ``other monitors'' as shown in
Table II.B-1 for diesel engines or Table II.C-1 for gasoline engines.
For engines in which no failure or deterioration of the VVT system
could result in an engine's emissions exceeding the applicable
emissions thresholds, the OBD system would have to detect a malfunction
of the VVT system when proper functional response of the system to
computer commands does not occur.
c. VVT and/or Control System Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for VVT target error or slow response malfunctions such that
the minimum performance ratio requirements discussed in section II.E
would be met with the exception that monitoring shall occur every time
the monitoring conditions are met during the driving cycle rather than
once per driving cycle as required for most monitors. For purposes of
tracking and reporting as required in section II.E, all monitors used
to detect all VVT related malfunctions would have to be tracked
separately but reported as a single set of values as specified in
section II.E.\42\
---------------------------------------------------------------------------
\42\ For specific components or systems that have multiple
monitors that are required to be reported (e.g., exhaust gas sensor
bank 1 may have multiple monitors for sensor response or other
sensor characteristics), the OBD system must separately track
numerators and denominators for each of the specific monitors and
report only the corresponding numerator and denominator for the
specific monitor that has the lowest numerical ratio. If two or more
specific monitors have identical ratios, the corresponding numerator
and denominator for the specific monitor that has the highest
denominator shall be reported for the specific component.
---------------------------------------------------------------------------
d. VVT and/or Control System MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2.
2. Engine Cooling System Monitoring
a. Background
We are concerned about two elements of the engine cooling system.
These elements are the thermostat and the engine coolant temperature
sensor. Manufacturers typically use a thermostat to control the flow of
coolant through the radiator and around the engine. During a cold
engine start, the thermostat is closed typically which prevents the
flow of coolant and serves to promote more rapid warm-up of the engine.
As the coolant approaches a specific temperature, the thermostat begins
to open allowing circulation of coolant through the radiator and around
the engine. The thermostat then acts to regulate the coolant to the
specified temperature. If the temperature rises above the regulated
temperature, the thermostat opens further to allow more coolant to
circulate, thus reducing the temperature. If the temperature drops
below the regulated temperature, the thermostat partially closes to
reduce the amount of coolant circulating, thereby increasing the
temperature. If a thermostat malfunctions in such a manner that it does
not adequately restrict coolant flow during vehicle warm-up, an
increase in emissions could occur due to prolonged operation of the
vehicle at temperatures below the stabilized, warmed-up value. This is
particularly true at lower ambient temperatures--50 degrees Fahrenheit
and below--but not so low that they are rare in the U.S. Equally
important is that the engine coolant temperature is often used as an
enable criterion for many OBD monitors. If the engine's coolant
temperature does not reach the
[[Page 3233]]
manufacturer-specified warmed-up value, such monitors would be
effectively disabled, perhaps indefinitely, and would, therefore, never
detect malfunctions.
Closely linked with the thermostat is the engine coolant
temperature (ECT) sensor. Manufacturers typically use an ECT sensor as
an input for many of the emission-related engine control systems. For
gasoline engines, the ECT sensor is often one of the most important
factors in determining when to begin closed-loop fuel control. If the
engine coolant does not warm-up sufficiently, closed-loop fuel control
is usually not engaged and the vehicle remains in open-loop fuel
control. Since open-loop fuel control does not provide the precision of
closed-loop control, the result is increased emissions levels. For
diesel engines, the ECT sensor is often used to engage closed-loop
control of the EGR system. Similar to closed-loop fuel control on
gasoline engines, if the coolant temperature does not warm up, closed-
loop control of the EGR system would not engage which would result in
increased emissions levels. In addition, for both gasoline and diesel
engines, the ECT sensor may be used to enable many of the monitors that
are being proposed. Such monitors would be effectively disabled and
incapable of detecting malfunctions should the ECT sensor itself
malfunction.
b. Engine Cooling System Monitoring Requirements
We are proposing that the OBD system monitor the thermostat on
engines so equipped for proper operation. We are also proposing that
the OBD system monitor the ECT sensor for circuit continuity, out-of-
range values, and rationality faults. For engines that use an approach
other than the cooling system and ECT sensor--e.g., oil temperature,
cylinder head temperature--for an indication of engine operating
temperature for emission control purposes (e.g., to modify spark or
fuel injection timing or quantity), the manufacturer may forego cooling
system monitoring in favor of monitoring the components or systems used
in their approach. To do so, the manufacturer would be required to
submit data and/or engineering analyses that demonstrate that their
monitoring plan is as reliable and effective as the monitoring required
for the engine cooling system.
i. Thermostat Monitoring Requirements
We are proposing that the OBD system detect a thermostat
malfunction if, within the manufacturer specified time interval
following engine start, any of the following conditions occur:
The coolant temperature does not reach the highest
temperature required by the OBD system to enable other diagnostics;
The coolant temperature does not reach a warmed-up
temperature within 20 degrees Fahrenheit of the manufacturer's nominal
thermostat regulating temperature. The manufacturer may use a lower
temperature for this criterion provided the manufacturer can
demonstrate that the fuel, spark timing, and/or other coolant
temperature-based modification to the engine control strategies would
not cause an emissions increase greater than or equal to 50 percent of
any of the applicable emissions standards.
The time interval specified by the manufacturer would have to be
supported by the manufacturer via data and/or engineering analyses
demonstrating that it provides robust monitoring and minimizes the
likelihood of other OBD monitors being disabled. The manufacturer may
use alternative malfunction criteria that are a function of temperature
at engine start on engines that do not reach the temperatures specified
in the malfunction criteria when the thermostat is functioning
properly. To do so, the manufacturer would be required to submit data
and/or engineering analyses that demonstrate that a properly operating
system does not reach the specified temperatures and that the
possibility is minimized for cooling system malfunctions to go
undetected and disable other OBD monitors. In some cases, a
manufacturer may forgo thermostat monitoring if the manufacturer can
demonstrate that a malfunctioning thermostat cannot cause a measurable
increase in emissions during any reasonable driving condition nor cause
any disablement of other OBD monitors.
ii. Engine Coolant Temperature Sensor Monitoring Requirements
We are proposing that the OBD system detect an ECT sensor
malfunction when a lack of circuit continuity or an out-of-range value
occurs. We are also proposing that the OBD system detect if, within the
manufacturer specified time interval following engine start, the ECT
sensor does not achieve the highest stabilized minimum temperature that
is needed to initiate closed-loop/feedback control of all affected
emission control systems (e.g., fuel system, EGR system). The
manufacturer specified time interval would have to be a function of the
engine coolant temperature and/or intake air temperature at startup.
The manufacturer time interval would also have to be supported by the
manufacturer via data and/or engineering analyses demonstrating that it
provides robust monitoring and minimizes the likelihood of other OBD
monitors being disabled. Manufacturers may forego the requirement to
detect the ``time to closed loop/feedback enable temperature''
malfunction if the manufacturer does not use engine coolant temperature
or the ECT sensor to enable closed-loop/feedback control of any
emission control systems.
We are also proposing that, to the extent feasible when using all
available information, the OBD system must detect a malfunction if the
ECT sensor inappropriately indicates a temperature below the highest
minimum enable temperature required by the OBD system to enable other
monitors. For example, an OBD system that requires an engine coolant
temperature greater than 140 degrees Fahrenheit prior to enabling an
OBD monitor must detect malfunctions that cause the ECT sensor to
indicate inappropriately a temperature below 140 degrees Fahrenheit.
Manufacturers may forego such monitoring within temperature regions in
which the thermostat monitor or the ECT sensor ``time to reach closed-
loop/feedback enable temperature'' monitor would detect this ``stuck in
a range below the highest minimum enable temperature'' ECT sensor
malfunction.
Lastly, we are proposing that, to the extent feasible when using
all available information, the OBD system must detect a malfunction if
the ECT sensor inappropriately indicates a temperature above the lowest
maximum enable temperature required by the OBD system to enable other
monitors. For example, an OBD system that requires an engine coolant
temperature less than 90 degrees Fahrenheit at startup prior to
enabling an OBD monitor must detect malfunctions that cause the ECT
sensor to indicate inappropriately a temperature above 90 degrees
Fahrenheit. Manufacturers may forego such monitoring within temperature
regions in which the thermostat monitor, the ECT sensor ``time to reach
closed-loop/feedback enable temperature'' monitor, or the ECT sensor
``stuck in a range below the highest minimum enable temperature''
monitor would detect this ECT sensor ``stuck in a range above the
lowest maximum enable temperature'' ECT sensor malfunction. The
manufacturer may also forego such monitoring if the MIL would be
illuminated for entering a ``limp home'' or default mode of
[[Page 3234]]
operation--e.g., for an over temperature protection strategy--as
discussed in section II.A.2. Manufacturers may also forego this
monitoring within temperature regions where the temperature gauge
indicates a temperature in the engine overheating ``red zone'' should
the vehicle have a temperature gauge on the instrument panel that
displays the same temperature information as used by the OBD system
(note that a temperature gauge would be required, not a temperature
warning light).
c. Engine Cooling System Monitoring Conditions
i. Thermostat Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for thermostat malfunctions in accordance with the general
monitoring conditions for all engines described in section II.A.3.
Additionally, monitoring for thermostat malfunctions would have to be
done once per drive cycle on every drive cycle in which the ECT sensor
indicates, at engine start, a temperature lower than the temperature
established as the malfunction criteria in section II.D.2.b.i.
Manufacturers would be allowed to disable thermostat monitoring at
ambient engine start temperatures below 20 degrees Fahrenheit.
Manufacturers may suspend or disable thermostat monitoring if the
engine is subjected to conditions that could lead to false diagnosis
(e.g., engine operation at idle for more than 50 percent of the warm-up
time and/or hot restart conditions). To do so, the manufacturer must
submit data and/or engineering analyses that demonstrate that the
suspension or disablement is necessary. In general, the manufacturer
would not be allowed to suspend or disable the thermostat monitor on
engine starts where the engine coolant temperature at engine start is
more than 35 degrees Fahrenheit lower than the thermostat malfunction
threshold temperature.
ii. Engine Coolant Temperature Sensor Monitoring Conditions
We are proposing that monitoring for ECT sensor circuit continuity
and out-of-range malfunctions be done continuously. Manufacturers would
be allowed to disable continuous ECT sensor monitoring when an ECT
sensor malfunction cannot be distinguished from other effects. To do
so, the manufacturer would have to submit test data and/or engineering
evaluation that demonstrate that a properly functioning sensor cannot
be distinguished from a malfunctioning sensor and that the disablement
interval is limited only to that necessary for avoiding false
detection.
We are also proposing that manufacturers define the monitoring
conditions for ``time to reach closed-loop/feedback enable
temperature'' malfunctions in accordance with the general monitoring
conditions for all engines described in section II.A.3. Additionally,
monitoring for ``time to reach closed-loop/feedback enable
temperature'' malfunctions would have to be conducted once per drive
cycle on every drive cycle in which the ECT sensor at engine start
indicates a temperature lower than the closed-loop enable temperature
(i.e., all engine start temperatures greater than the ECT sensor out-
of-range low temperature and less than the closed-loop enable
temperature). Manufacturers would be allowed to suspend or delay the
``time to reach closed-loop/feedback enable temperature'' monitor if
the engine is subjected to conditions that could lead to false
diagnosis (e.g., vehicle operation at idle for more than 50 to 75
percent of the warm-up time).
We are also proposing that manufacturers define the monitoring
conditions for ECT sensor ``stuck in a range below the highest minimum
enable temperature'' and ``stuck in a range above the lowest maximum
enable temperature'' malfunctions in accordance with the general
monitoring conditions for all engines described in section II.A.3 and
in accordance with the minimum performance ratio requirements discussed
in section II.E.
d. Engine Cooling System MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2.
3. Crankcase Ventilation System Monitoring
a. Background
Crankcase emissions are the pollutants emitted in the gases that
are vented from an engine's crankcase. These gases are also referred to
as ``blowby gases'' because they result from engine exhaust from the
combustion chamber ``blowing by'' the piston rings into the crankcase.
These gases are vented to prevent high pressures from occurring in the
crankcase. Our emission standards have historically prohibited
crankcase emissions from all highway engines except turbocharged heavy-
duty diesel engines. The most common way to eliminate crankcase
emissions has been to vent the blowby gases into the engine air intake
system, so that the gases can be recombusted. We made the exception for
turbocharged heavy-duty diesel engines in the past because of concerns
about fouling that could occur by routing the diesel particulates
(including engine oil) into the turbocharger and aftercooler. Newly
developed closed crankcase filtration systems specifically designed for
turbocharged heavy-duty diesel engines now allow the crankcase gases to
be captured.
In general, the crankcase ventilation system consists of a fresh
air inlet hose, a crankcase vapor outlet hose, and a crankcase
ventilation valve to control the flow through the system. Fresh air is
introduced to the crankcase via the inlet (typically a connection from
the intake air cleaner assembly). On the opposite side of the
crankcase, vapors are vented from the crankcase through the valve by
way of the outlet hose and then to the intake manifold. On gasoline
engines, the intake manifold provides the vacuum that is needed to
accomplish the circulation while the engine is running.
For gasoline engines, the valve is used to regulate the amount of
flow based on engine speed. During low engine load operation (e.g.,
idle), the valve is nearly closed allowing only a small portion of air
to flow through the system. With open throttle conditions, the valve
opens to allow more air into the system. At high engine load operation
(i.e., hard accelerations), the valve begins to close again, limiting
air flow to a small amount. For most systems, a mechanical valve is all
that is necessary to adequately regulate crankcase ventilation system
air flow. The crankcase ventilation system on diesel engines, while
slightly different than that for gasoline engines, has essentially the
same purpose and function.
We do not believe that failures involving cracked or deteriorated
hoses have a significant impact on crankcase emissions because vapors
are drawn into the engine by intake manifold vacuum which suggests that
fresh air would be drawn into the cracked hose rather than dirty
exhaust being blown out of the cracked hose. The more likely cause of
crankcase ventilation system malfunctions and excess emissions is
improper service or tampering of the system. Such failures include
misrouted or disconnected hoses and missing valves. Of these failures,
hose disconnections on the vapor vent side of the system and/or missing
valves can cause harmful crankcase emissions to be vented directly to
the atmosphere.
[[Page 3235]]
b. Crankcase Ventilation System Monitoring Requirements
We are proposing that the OBD system monitor the crankcase
ventilation system on engines so equipped for system integrity. Engines
not equipped with crankcase ventilation systems would be exempt from
monitoring the crankcase ventilation system.
Specifically for diesel engines, the manufacturer would be required
to submit a plan for the monitoring strategy, malfunction criteria, and
monitoring conditions prior to OBD certification. The plan would have
to demonstrate the effectiveness of the strategy to monitor the
performance of the crankcase ventilation system to the extent feasible
with respect to the malfunction criteria below and the monitoring
conditions required by the monitor.
We are proposing that the OBD system detect a malfunction of the
crankcase ventilation system when a disconnection of the system occurs
between either the crankcase and the crankcase ventilation valve, or
between the crankcase ventilation valve and the intake manifold.
Manufacturers may forego detecting a disconnection between the
crankcase and the crankcase ventilation valve provided the manufacturer
can demonstrate that the crankcase ventilation system is designed such
that the crankcase ventilation valve is fastened directly to the
crankcase in a manner that makes it significantly more difficult to
remove the valve from the crankcase than to disconnect the line between
the valve and the intake manifold (aging effects must be taken into
consideration). Manufacturers may also forego detecting a disconnection
between the crankcase and the crankcase ventilation valve for system
designs that use tubing between the valve and the crankcase provided
the manufacturer can demonstrate that the connections between the valve
and the crankcase are: (1) Resistant to deterioration or accidental
disconnection; (2) significantly more difficult to disconnect than the
line between the valve and the intake manifold; and, (3) not subject to
disconnection per the manufacturer's repair procedures for non-
crankcase ventilation system repair work. Lastly, manufacturers may
forego detecting a disconnection between the crankcase ventilation
valve and the intake manifold upon determining that the disconnection:
(1) Causes the vehicle to stall immediately during idle operation; or,
(2) is unlikely to occur due to a crankcase ventilation system design
that is integral to the induction system (e.g., machined passages
rather than tubing or hoses).
c. Crankcase Ventilation System Monitoring Conditions
We are proposing that manufacturers define the monitoring
conditions for crankcase ventilation system malfunctions in accordance
with the general monitoring conditions for all engines described in
section II.A.3, and the minimum performance ratio requirements
discussed in section II.E.
d. Crankcase Ventilation System MIL Illumination and DTC Storage
We are proposing the general requirements for MIL illumination and
DTC storage as discussed in section II.A.2. The stored DTC need not
specifically identify the crankcase ventilation system (e.g., a DTC for
idle speed control or fuel system monitoring can be stored) if the
manufacturer can demonstrate that additional monitoring hardware would
be necessary to make this identification, and provided the
manufacturer's diagnostic and repair procedures for the detected
malfunction include directions to check the integrity of the crankcase
ventilation system.
4. Comprehensive Component Monitors
a. Background
Comprehensive components is a term meant to capture essentially
every other emissions related component not discussed above.
Specifically, it covers all other electronic engine components or
systems not mentioned above that either can affect vehicle emissions or
are used as part of the OBD diagnostic strategy for another monitored
component or system. Comprehensive components are generally identified
as input components--i.e., those that provide input directly or
indirectly to the onboard computer--or as output components and/or
systems--i.e., those that receive commands from the onboard computer.
Typical examples of input components include temperature sensors and
pressure sensors, while examples of output components and/or systems
include the idle control system, glow plugs, and wait-to-start lamps.
While a malfunctioning comprehensive component may not have as much
impact on emissions as a malfunctioning major emissions-related
component, it still could result in a measurable increase in emissions.
The proper performance of these components can be critical to both the
proper functioning of major emissions-related components, and to the
accurate monitoring of those components or systems. Malfunctions of
comprehensive components that go undetected by the OBD system may
disable or adversely affect the robustness of other OBD monitors
without any awareness by the operator that a problem exists. Due to the
vital role these components play, monitoring them properly is extremely
important.
b. Comprehensive Component Monitoring Requirements
We are proposing that the OBD system monitor for malfunction any
electronic engine components/systems not otherwise described in
sections above that either provides input to (directly or indirectly)
or receives commands from the onboard computer(s), and: (1) Can affect
emissions during any reasonable in-use driving condition; or, (2) is
used as part of the diagnostic strategy for any other monitored system
or component.\43\
---------------------------------------------------------------------------
\43\ When referring to ``comprehensive components'' and their
monitors, ``electronic engine components/systems'' is not meant to
include components/systems that are driven by the engine yet are not
related to the control of the fueling, air handling, or emissions of
the engine (e.g., PTO components, air conditioning system
components, and power steering components are not included).
---------------------------------------------------------------------------
Input components required to be monitored may include the crank
angle sensor, knock sensor, throttle position sensor, cam position
sensor, intake air temperature sensor, boost pressure sensor, manifold
pressure sensor, mass air flow sensor, exhaust temperature sensor,
exhaust pressure sensor, fuel pressure sensor, and fuel composition
sensor (e.g., flexible fuel vehicles). Output components/systems
required to be monitored may include the idle speed control system,
glow plug system, variable length intake manifold runner systems,
supercharger or turbocharger electronic components, heated fuel
preparation systems, the wait-to-start lamp on diesel applications, and
the MIL. The manufacturer would be responsible for determining which
input and output components/systems could affect emissions during any
reasonable in-use driving condition. The manufacturer would be allowed
to make this determination based on data or engineering judgment.
However, if the Administrator reasonably believes that a manufacturer
has incorrectly determined that a component/system cannot affect
emissions, the manufacturer may be required to provide emissions data
showing that the component/system, when malfunctioning and installed in
a suitable test engine, does not have an emissions effect. Such
emissions data may be requested for any reasonable driving condition.
[[Page 3236]]
i. Input Components
We are proposing that the OBD system detect malfunctions of input
components caused by a lack of circuit continuity, out-of-range values,
and, where feasible, improper rationality. To the extent feasible, the
rationality diagnostics should verify that a sensor's input to the
onboard computer is neither inappropriately high nor inappropriately
low (i.e., ``two-sided'' diagnostics should be used). Also to the
extent feasible, the OBD system should detect and store different DTCs
that distinguish rationality malfunctions from lack of circuit
continuity malfunctions and out-of-range values. For lack of circuit
continuity malfunctions and out-of-range values, the OBD system should
detect and store different DTCs for each distinct malfunction (e.g.,
out-of-range low, out-of-range high, open circuit). The OBD system is
not required to store separate DTCs for lack of circuit continuity
malfunctions that cannot be distinguished from malfunctions associated
with out-of-range values.
For input components that are used to activate alternative
strategies that can affect emissions (e.g., AECDs, engine shutdown
systems), the OBD system would be required to detect rationality
malfunctions that cause the system to erroneously activate or
deactivate the alternative strategy. To the extent feasible when using
all available information, the rationality diagnostics should detect a
malfunction if the input component inappropriately indicates a value
that activates or deactivates the alternative strategy. For example, if
an alternative strategy requires an intake air temperature greater than
120 degrees Fahrenheit prior to activating, the OBD system should
detect malfunctions that cause the intake air temperature sensor to
inappropriately indicate a temperature above 120 degrees Fahrenheit.
For engines that require precise alignment between the camshaft and
the crankshaft, the OBD system would be required to monitor the
crankshaft position sensor(s) and camshaft position sensor(s) to verify
proper alignment between the camshaft and crankshaft. The OBD system
would also have to monitor the sensors for circuit continuity and
rationality malfunctions. Such monitoring for proper alignment between
a camshaft and a crankshaft would only be required in cases where both
are equipped with position sensors.
For engines equipped with VVT systems and a timing belt or chain,
the OBD system must detect a malfunction if the alignment between the
camshaft and crankshaft is off by one or more cam/crank sprocket cogs
(e.g., the timing belt/chain has slipped by one or more teeth/cogs). If
a manufacturer demonstrates that a single tooth/cog misalignment cannot
cause a measurable increase in emissions during any reasonable driving
condition, the OBD system would be required to detect a malfunction
when the minimum number of teeth/cogs misalignment needed to cause a
measurable emission increase has occurred.
ii. Output Components/Systems
We are proposing that the OBD system detect a malfunction of an
output component/system when proper functional response of the
component/system to computer commands does not occur. If a functional
check is not feasible, the OBD system would be required to detect
malfunctions caused by a lack of circuit continuity (e.g., short to
ground or high voltage). For output component malfunctions associated
with the lack of circuit continuity, the OBD system is not required to
store different DTCs for each distinct malfunction (e.g., open circuit,
shorted low). Further, manufacturers would not be required to activate
an output component/system when it would not normally be active for the
exclusive purpose of performing functional monitoring of output
components/systems.
Additionally, the idle control system would have to be monitored
for proper functional response to computer commands. For gasoline
engines that use monitoring strategies based on deviation from target
idle speed, a malfunction would have to be detected when either of the
following conditions occur: (a) The idle speed control system cannot
achieve the target idle speed within 200 revolutions per minute (rpm)
above the target speed or 100 rpm below the target speed--the OBD
system could use larger engine speed tolerances provided the
manufacturer is able to demonstrate via data and/or engineering
analyses that the tolerances can be exceeded without a malfunction
being present; or, (b) the idle speed control system cannot achieve the
target idle speed within the smallest engine speed tolerance range
required by the OBD system to enable any other OBD monitors. For diesel
engines, a malfunction would have to be detected when either of the
following conditions occur: (a) The idle fuel control system cannot
achieve the target idle speed or fuel injection quantity within +/-50
percent of the manufacturer-specified fuel quantity and engine speed
tolerances; or, (b) the idle fuel control system cannot achieve the
target idle speed or fueling quantity within the smallest engine speed
or fueling quantity tolerance range required by the OBD system to
enable any other OBD monitors.
Glow plugs and intake air heater systems would also have to be
monitored for proper functional response to computer commands and for
malfunctions associated with circuit continuity. The glow plug and
intake air heater circuit(s) would have to be monitored for proper
current and voltage drop. The manufacturer may use other monitoring
strategies by submitting data and/or engineering analyses that
demonstrate that the strategy provides equally reliable and timely
detection of malfunctions. In general, the OBD system would have to
detect a malfunction when a single glow plug no longer operates within
the manufacturer's specified limits for normal operation. If a
manufacturer demonstrates that a single glow plug malfunction cannot
cause a measurable increase in emissions during any reasonable driving
condition, the OBD system must detect a malfunction for the minimum
number of glow plugs needed to cause an emissions increase. Further, to
the extent feasible without adding additional hardware for this
purpose, the stored DTC must identify the specific malfunctioning glow
plug(s).
Lastly, the wait-to-start lamp circuit and the MIL circuit would
have to be monitored for malfunctions that cause either lamp to fail to
illuminate when commanded on (e.g., burned out bulb).
c. Comprehensive Component Monitoring Conditions
i. Input Components
We are proposing that input components be monitored continuously
for circuit continuity and for providing values within the proper
range. For rationality monitoring, where applicable, manufacturers
would define the monitoring conditions for detecting malfunctions in
accordance with the general monitoring conditions for all engines
described in section II.A.3 and the minimum performance ratio
requirements described in section II.E except that rationality
monitoring would have to occur every time the monitoring conditions are
met during the drive cycle rather than once per drive cycle as required
in section II.A.3.
A manufacturer may disable continuous monitoring for circuit
continuity, and for providing values within the proper range, when a
[[Page 3237]]
malfunction cannot be distinguished from other effects. To do so, the
manufacturer would have to submit data and/or engineering analyses that
demonstrate that a properly functioning input component cannot be
distinguished from a malfunctioning input component and that the
disablement interval is limited only to that necessary for avoiding
false detection.
ii. Output Components/Systems
We are proposing that output components/systems be monitored
continuously for circuit continuity. For functional monitoring,
manufacturers would define the monitoring conditions for detecting
malfunctions in accordance with the general monitoring conditions for
all engines described in section II.A.3 and the minimum performance
ratio requirements described in section II.E.
For the idle control system, we are proposing that manufacturers
define the monitoring conditions for functional monitoring in
accordance with the general monitoring conditions for all engines
described in section II.A.3 and the minimum performance ratio
requirements described in section II.E except that functional
monitoring would have to occur every time the monitoring conditions are
met during the drive cycle rather than once per drive cycle as required
in section II.A.3.
A manufacturer may disable continuous monitoring for circuit
continuity when a malfunction cannot be distinguished from other
effects. To do so, the manufacturer would have to submit data and/or
engineering analyses that demonstrate that a properly functioning
output component cannot be distinguished from a malfunctioning output
component and that the disablement interval is limited only to that
necessary for avoiding false detection.
d. Comprehensive Component MIL Illumination and DTC Storage
With a couple of exceptions, we are proposing the general
requirements for MIL illumination and DTC storage as discussed in
section II.A.2. The exceptions to this being that MIL illumination
would not be required in conjunction with storing a MIL-on DTC for any
comprehensive component if: (a) The component or system, when
malfunctioning, could not cause engine emissions to increase by 15
percent or more of the FTP standard during any reasonable driving
condition; and, (b) the component or system is not used as part of the
diagnostic strategy for any other monitored system or component. MIL
illumination is also not required if a malfunction has been detected in
the MIL circuit that prevents the MIL from illuminating (e.g., burned
out bulb or light emitting diode (LED)). However, the electronic MIL
status must be reported as ``commanded on'' and a MIL-on DTC would have
to be stored.
5. Other Emissions Control System Monitoring
a. Background
As noted above, the primary purpose of OBD is to detect
malfunctions in the engine and/or emissions control system. Therefore,
we are proposing that manufacturers be required to submit to the
Administrator a monitoring plan for any new engine and/or emissions
control technology not otherwise described above. Such technology might
include hydrocarbon traps or homogeneous charge compression ignition
(HCCI) systems. This would allow manufacturers and EPA to evaluate the
new technology and determine an appropriate level of monitoring that
would be both technologically feasible and consistent with the
monitoring requirements for the other emissions control devices
described above.
As proposed, the Administrator would provide guidance as to what
type of components would fall under the ``other emissions control
system'' requirements and which would fall under the comprehensive
component requirements. Specifically, we are concerned that uncertainty
may arise for those emission control components or systems that also
meet the definition of electronic engine components. As such, the
proposal would delineate the two by requiring components/systems that
fit both definitions but are not corrected or compensated for by the
adaptive fuel control system to be monitored as ``other emissions
control devices'' rather than as comprehensive components. A typical
device that would fall under this category instead of the comprehensive
components category because of this delineation would be a swirl
control valve system. Such delineation is necessary because such
emissions control components generally require more thorough monitoring
than comprehensive components to ensure low emissions levels throughout
an engine's life. Further, emissions control components that are not
compensated for by the fuel control system as they age or deteriorate
can have a larger impact on tailpipe emissions than is typical of
comprehensive components that are corrected for by the fuel control
system as they deteriorate.
Note that the Administrator does not foresee any outcome where a
promising new emissions control technology would be prohibited based
solely on the lack of an OBD monitoring strategy for it. Instead, we
want to instill in manufacturers the need to consider OBD monitoring
when developing any new emissions control technology. Further, we want
to instill in manufacturers the sense that an OBD monitoring strategy
will, one day, be necessary so a plan for such should exist prior to
introducing the technology on new products.
b. Other Emissions Control System Monitoring Requirements/Conditions
We are proposing that, for other emission control systems that are:
(1) Not identified or addressed in sections II.B through II.D.4--e.g.,
hydrocarbon traps, HCCI control systems; or, (2) identified or
addressed in section II.D.4 but not corrected or compensated for by an
adaptive control system--e.g., swirl control valves, manufacturers
would be required to submit a plan for Administrator approval of the
monitoring strategy, the malfunction criteria, and the monitoring
conditions prior to introduction on a production engine. Administrator
approval of the plan would be based on the effectiveness of the
monitoring strategy, the robustness of the malfunction criteria, and
the frequency of meeting the necessary monitoring conditions.
We are also proposing that, for engines that use emissions control
systems that alter intake air flow or cylinder charge characteristics
by actuating valve(s), flap(s), etc., in the intake air delivery system
(e.g., swirl control valve systems), the manufacturers, in addition to
meeting the requirements above, may elect to have the OBD system
monitor the shaft to which all valves in one intake bank are physically
attached rather than monitoring the intake air flow, cylinder charge,
or individual valve(s)/flap(s) for proper functional response. For non-
metal shafts or segmented shafts, the monitor must verify all shaft
segments for proper functional response (e.g., by verifying the segment
or portion of the shaft furthest from the actuator functions properly).
For systems that have more than one shaft to operate valves in multiple
intake banks, manufacturers are not required to add more than one set
of detection hardware (e.g., sensor, switch) per intake bank to meet
this requirement.
[[Page 3238]]
6. Exceptions to Monitoring Requirements
a. Background
Under some conditions, the reliability of specific monitors may be
diminished significantly. Therefore, we are proposing to allow
manufacturers to disable the affected monitors when these conditions
are encountered in-use. These include situations of extreme conditions
(e.g., very low ambient temperatures, high altitudes) and of periods
where default modes of operation are active (e.g., when a tire pressure
problem is detected). In some of these cases, we may allow
manufacturers to revise the emission malfunction threshold to ensure
the most reliable monitoring performance.
b. Requirements for Exceptions to Monitoring
The Administrator may revise the emission threshold for any
monitor, or revise the PM filtering performance malfunction criteria
for DPFs to exclude detection of specific failure modes such as
partially melted substrates, if the most reliable monitoring method
developed requires a higher threshold or, in the case of PM filtering
performance, the exclusion of specific failure modes, to prevent
significant errors of commission in detecting a malfunction. The
Administrator would notify the industry of any such revisions to ensure
that all manufacturers would be able to implement OBD on an equal
basis. In other words, we would not allow one manufacturer to revise a
specific monitoring threshold upwards while insisting that another meet
the proposed threshold.
Manufacturers may disable an OBD system monitor at ambient engine
start temperatures below 20 degrees Fahrenheit (low ambient temperature
conditions may be determined based on intake air or engine coolant
temperature at engine start) or at elevations higher than 8000 feet
above sea level. To do so, the manufacturer would have to submit data
and/or engineering analyses that demonstrate that monitoring would be
unreliable during the disable conditions. A manufacturer may request
that an OBD system monitor be disabled at other ambient engine start
temperatures by submitting data and/or engineering analyses
demonstrating that misdiagnosis would occur at the given ambient
temperatures due to their effect on the component itself (e.g.,
component freezing).
Manufacturers may disable an OBD system monitor when the fuel level
is 15 percent or less of the nominal fuel tank capacity for those
monitors that can be affected by low fuel level or running out of fuel
(e.g., misfire detection). To do so, the manufacturer would have to
submit data and/or engineering analyses that demonstrate that both
monitoring at the given fuel levels would be unreliable, and the OBD
system is still able to detect a malfunction if the component(s) used
to determine fuel level indicates erroneously a fuel level that causes
the disablement.
Manufacturers may disable OBD monitors that can be affected by
vehicle battery or system voltage levels. For an OBD monitor affected
by low vehicle battery or system voltages, manufacturers may disable
monitoring when the battery or system voltage is below 11.0 Volts.
Manufacturers may use a voltage threshold higher than 11.0 Volts to
disable monitors but would have to submit data and/or engineering
analyses that demonstrate that monitoring at those voltages would be
unreliable and that either operation of a vehicle below the disablement
criteria for extended periods of time is unlikely or the OBD system
monitors the battery or system voltage and would detect a malfunction
at the voltage used to disable other monitors.
For monitoring systems affected by high vehicle battery or system
voltages, manufacturers may disable monitoring when the battery or
system voltage exceeds a manufacturer-defined voltage. To do so, the
manufacturer would have to submit data and/or engineering analyses that
demonstrate that monitoring above the manufacturer-defined voltage
would be unreliable and that either the electrical charging system/
alternator warning light would be illuminated (or voltage gauge would
be in the ``red zone'') or the OBD system monitors the battery or
system voltage and would detect a malfunction at the voltage used to
disable other monitors.
A manufacturer may also disable affected OBD monitors in vehicles
designed to accommodate the installation of power take off (PTO) units
provided disablement occurs only while the PTO unit is active and the
OBD readiness status is cleared by the onboard computer (i.e., all
monitors set to indicate ``not complete'') while the PTO unit is
activated (see section II.F.4 below). If the disablement occurs, the
readiness status may be restored, when the disablement ends, to its
state prior to PTO activation.
E. A Standardized Method To Measure Real World Monitoring Performance
As was noted in section II.A.3, manufacturers determine the most
appropriate times to run the non-continuous OBD monitors. This way,
they are able to make their OBD evaluation either at the operating
condition when an emissions control system is active and its
operational status can best be evaluated, and/or at the operating
condition when the most accurate evaluation can be made (e.g., highly
transient conditions or extreme conditions can make evaluation
difficult). Importantly, manufacturers are prohibited from using a
monitoring strategy that is so restrictive such that it rarely or never
runs. To help protect against monitors that rarely run, we are
proposing an ``in-use monitor performance ratio'' requirement as
described here.
The set of operating conditions that must be met so that an OBD
monitor can run are called the ``enable criteria'' for that given
monitor. These enable criteria are often different for different
monitors and may well be different for different types of engines. A
large diesel engine intended for use in a Class 8 truck would be
expected to see long periods of relatively steady-state operation while
a smaller engine intended for use in an urban delivery truck would be
expected to see a lot of transient operation. Manufacturers will need
to balance between a rather loose set of enable criteria for their
engines and vehicles given the very broad range of operation HD highway
engines see and a tight set of enable criteria given the desire for
greater monitor accuracy. Manufacturers would be required to design
these enable criteria so that the monitor:
Is robust (i.e., accurate at making pass/fail decisions);
Runs frequently in the real world; and,
In general, also runs during the FTP heavy-duty transient
cycle.
If designed incorrectly, these enable criteria may be either too
broad and result in inaccurate monitors, or overly restrictive thereby
preventing the monitor from executing frequently in the real world.
Since the primary purpose of an OBD system is to monitor for and
detect emission-related malfunctions while the engine is operating in
the real world, a standardized methodology for quantifying real world
performance would be beneficial to both EPA and manufacturers.
Generally, in determining whether a manufacturer's monitoring
conditions are sufficient, a manufacturer would discuss the proposed
monitoring conditions with EPA staff. The finalized conditions would be
included in the certification applications and submitted to EPA staff
who would review the conditions and make determinations on a case-by-
case
[[Page 3239]]
basis based on the engineering judgment of the staff. In cases where we
are concerned that the documented conditions may not be met during
reasonable in-use driving conditions, we would most likely ask the
manufacturer for data or other engineering analyses used by the
manufacturer to determine that the conditions would occur in-use. In
proposing a standardized methodology for quantifying real world
performance, we believe this review process can be done more
efficiently than would occur otherwise. Furthermore, it would serve to
ensure that all manufacturers are held to the same standard for real
world performance. Lastly, we want review procedures that will ensure
that monitors operate properly and frequently in the field.
Therefore, we are proposing that all manufacturers be required to
use a standardized method for determining real world monitoring
performance and to hold manufacturers liable if monitoring occurs less
frequently than a minimum acceptable level, expressed as minimum
acceptable in-use performance ratio. We are also proposing that
manufacturers be required to implement software in the onboard computer
to track how often several of the major monitors (e.g., catalyst, EGR,
CDPF, other diesel aftertreatment devices) execute during real world
driving. The onboard computer would keep track of how many times each
of these monitors has executed and how much the engine has been
operated. By measuring both of these values, the ratio of monitor
operation relative to engine operation can be calculated to determine
monitoring frequency.
The proposed minimum acceptable frequency requirement would apply
to many but not all of the OBD monitors. We are proposing that monitors
be required to operate either continuously, once per drive cycle, or,
in a few cases, multiple times per drive cycle (i.e., whenever the
proper monitoring conditions are present). For components or systems
that are more likely to experience intermittent failures or failures
that can routinely happen in distinct portions of an engine's operating
range (e.g., only at high engine speed and load, only when the engine
is cold or hot), monitors would be required to operate continuously.
Examples of continuous monitors include the fuel system monitor and
most electrical/circuit continuity monitors. For components or systems
that are less likely to experience intermittent failures or failures
that only occur in specific vehicle operating regions or for components
or systems where accurate monitoring can only be performed under
limited operating conditions, monitors would be required to run once
per drive cycle. Examples of once per drive cycle monitors typically
include gasoline catalyst monitors, evaporative system leak detection
monitors, and output comprehensive component functional monitors. For
components or systems that are routinely used to perform functions that
are crucial to maintaining low emissions but may still require
monitoring under fairly limited conditions, monitors would be required
to run each and every time the manufacturer-defined enable conditions
are present. Examples of multiple times per drive cycle monitors
typically include input comprehensive component rationality monitors
and some exhaust aftertreatment monitors.
Monitors required to run continuously, by definition, would always
be running, thereby making a minimum frequency requirement moot. The
new frequency requirement would essentially apply only to those
monitors that are designated as once per drive cycle or multiple times
per drive cycle monitors. For all of these monitors, manufacturers
would be required to define monitoring conditions that ensure adequate
frequency in-use. Specifically, the monitors would need to run often
enough so that the measured monitor frequency on in-use engines would
exceed the minimum acceptable frequency. However, even though the
minimum frequency requirement would apply to nearly all once per drive
cycle and multiple times per drive cycle monitors, manufacturers would
only be required to implement software to track and report the in-use
frequency for a few of the major monitors. These few monitors generally
represent the major emissions control components and the ones with the
most limited enable criteria.
We believe that OBD monitors should run frequently to ensure early
detection of emissions-related malfunctions and, consequently, to
maintain low emissions. Allowing malfunctions to continue undetected
and unrepaired for long periods of time allows emissions to increase
unnecessarily. Frequent monitoring can also help to ensure detection of
intermittent emissions-related malfunctions (i.e., those that are not
continuously present but occur sporadically for days and even weeks at
a time). The nature of mechanical and electrical systems is that
intermittent malfunctions can and do occur. The less frequent the
monitoring, the less likely these malfunctions will be detected and
repaired. Additionally, for both intermittent and continuous
malfunctions, earlier detection is equivalent to preventative
maintenance in that the original malfunction can be detected and
repaired prior to it causing subsequent damage to other components.
This can help vehicle operators avoid more costly repairs that could
have resulted had the first malfunction gone undetected.
Infrequent monitoring can also have an impact on the service and
repair industry. Specifically, monitors that have unreasonable or
overly restrictive enable conditions could hinder vehicle repair
services. In general, upon completing an OBD-related repair to an
engine, a technician will attempt to verify that the repair has indeed
fixed the problem. Ideally, a technician will operate the vehicle in a
manner that will exercise the appropriate OBD monitor and allow the OBD
system to confirm that the malfunction is no longer present. This
affords a technician the highest level of assurance that the repair was
indeed successful. However, OBD monitors that operate infrequently are
difficult to exercise and, therefore, technicians may not be able (or
may not be likely) to perform such post-repair evaluations. Despite the
service information availability requirements we are proposing--
requirements that manufacturers make all of their service and repair
information available to all technicians, including the information
necessary to exercise OBD monitors--technicians would still find it
difficult to exercise monitors that require infrequently encountered
engine operating conditions (e.g., abnormally steady constant speed
operation for an extended period of time). Additionally, to execute OBD
monitors in an expeditious manner or to execute monitors that would
require unusual or infrequently encountered conditions, technicians may
be required to operate the vehicle in an unsafe manner (e.g., at
freeway speeds on residential streets or during heavy traffic). If
unsuccessful in executing these monitors, technicians may even take
shortcuts in attempting to validate the repair while maintaining a
reasonable cost for customers. These shortcuts would likely not be as
thorough in verifying repairs and could increase the chance that
improperly repaired engines would be returned to the vehicle owner or
additional repairs would be performed just to ensure the problem is
fixed. In the end, monitors that operate less frequently can result in
unnecessary costs and inconvenience to both vehicle owners and
technicians.
[[Page 3240]]
1. Description of Software Counters to Track Real World Performance
As stated above, manufacturers would be required to track monitor
peformance by comparing the number of monitoring events (i.e., how
often each monitor has run) to the number of driving events (i.e., how
often has the vehicle been operated). The ratio of these two numbers
would give an indication of how often the monitor is operating relative
to vehicle operation. In equation form, this can be stated as:
[GRAPHIC] [TIFF OMITTED] TP24JA07.004
To ensure that all manufacturers are tracking in-use performance in
the same manner, we are proposing very detailed requirements for
defining and incrementing both the numerator and denominator of this
ratio. Manufacturers would be required to keep track of separate
numerators and denominators for each of the major monitors, and to
ensure that the data are saved every time the engine is shut off. The
numerators and denominators would be reset to zero only in extreme
circumstances when the non-volatile memory has been cleared (e.g., when
the onboard computer has been reprogrammed in the field or when the
onboard computer memory has been corrupted). The values would not be
reset to zero during normal occurrences such as clearing of stored DTCs
or performing routine service or maintenance.
Further, the numerator and denominator would be structured such
that their maximum values would be 65,535 which is the maximum number
that can be stored in a 2-byte location. This would ensure that
manufacturers allocate sufficient and consistent memory space in the
onboard computer. If either the numerator or denominator for a
particular monitor reaches the maximum value, both values for that
particular monitor would be divided by two before counting resumes. In
general, the numerator and denominator would only be allowed to
increment a maximum of once per drive cycle because most of the major
monitors are designed to operate only once per drive cycle.
Additionally, incrementing of both the numerator and denominator for a
particular monitor would be disabled (i.e., paused but the stored
values would not be erased or reset) only when a problem has been
detected (i.e., a pending or MIL-on DTC has been stored) that prevents
the monitor from executing. Once the problem is no longer detected and
any stored DTCs associated with the problem have been erased, either
through the allowable self-clearing process or upon command by a
technician via a scan tool, incrementing of both the numerator and
denominator would resume.
SAE has developed standards for storing and reporting the data to a
generic scan tool. This would help ensure that all manufacturers report
the data in an identical manner which should ease data collection in
the field.
a. Number of Monitoring Events (``Numerator'')
For the numerator, manufacturers would be required to keep a
separate numeric count of how often each of the particular monitors has
operated. More specifically, manufacturers would have to implement a
software counter that increments by one every time the particular
monitor meets all of the enable/monitoring conditions for a long enough
period of time such that a malfunctioning component would have been
detected. For example, if a manufacturer requires a vehicle to be
warmed-up and at idle for 20 seconds continuously to detect a
malfunctioning catalyst, the catalyst monitor numerator could only be
incremented if the vehicle actually operates simultaneously in all of
those conditions. If the vehicle is operated in some but not all of the
conditions (e.g., at idle but not warmed-up), the numerator would not
be allowed to increment because the monitor would not have been able to
detect a malfunctioning catalyst since all of the conditions were not
satisfied simultaneously.
Another complication is the difference between a monitor reaching a
``pass'' or ``fail'' decision. At first glance, it would appear that a
manufacturer should simply increment the numerator anytime the
particular monitor reaches a decision, be it ``pass'' or ``fail''.
However, monitoring strategies may have a different set of criteria
that must be met to reach a ``pass'' decision versus a ``fail''
decision. As a simple example, a manufacturer may appropriately require
only 10 seconds of operation at idle to reach a ``pass'' decision but
require 30 seconds of operation at idle to reach a ``fail'' decision.
Manufacturers would not be allowed to increment the numerator if the
vehicle had idled for 10 seconds and reached a ``pass'' decision since
insufficient time had passed to allow for a possible ``fail'' decision.
This is necessary because the primary function of OBD systems is to
detect malfunctions (i.e., to correctly reach ``fail'' decisions, not
``pass'' decisions) and, thus, the real world ability of the monitors
to detect malfunctions is the parameter we want most to measure.
Therefore, monitors with different criteria to reach a ``pass''
decision versus a ``fail'' decision would not be allowed to increment
the numerator solely upon satisfying the ``pass'' criteria.
The correct implementation of the numerator counters by
manufacturers is imperative to ensure a reliable measure for
determining real world performance. ``Overcounting'' would falsely
indicate the monitor is executing more often than it really is, while
``undercounting'' would make it appear as if the monitor is not running
as often as it really is. Manufacturers would be required to describe
their numerator incrementing strategy in their certification
documentation and to verify the proper performance of their strategy
during production vehicle evaluation testing.
b. Number of Driving Events (``Denominator'')
We are also proposing that manufacturers separately track how often
the engine is operated. Basically, the denominator would be a counter
that increments by one each time the engine is operated. We are
proposing that the denominator counter be incremented by one only if
several criteria are satisfied during a single drive cycle. This allows
very short trips or trips during extreme conditions such as very cold
temperatures or very high altitude to be filtered out and excluded from
the count. This is appropriate because these are also conditions where
most OBD monitors are neither expected nor required to operate.
Specifically, the denominator would be incremented if, on a single
key start, the following criteria were satisfied while ambient
temperature remained above 20 degrees Fahrenheit and altitude remained
below 8,000 feet:
Minimum engine run time of 10 minutes;
[[Page 3241]]
Minimum of 5 minutes, cumulatively, of operation at
vehicle speeds greater than 25 miles-per-hour for gasoline engines or
calculated load greater than 15 percent for diesel engines; and
At least one continuous idle for a minimum of 30 seconds
encountered.
We intend to work with industry to collect data during the first
few years of implementation and make any adjustments, if necessary, to
the criteria used to increment the denominator to ensure that the in-
use performance ratio provides a meaningful measure of in-use
monitoring performance.
2. Proposed Performance Tracking Requirements
a. In-use Monitoring Performance Ratio Definition
For monitors required to meet the in-use performance tracking
requirements,\44\ we are proposing that the incrementing of numerators
and denominators and the calculation of the in-use performance ratio be
done in accordance with the following specifications.
---------------------------------------------------------------------------
\44\ These monitors, as presented in section II.A.3, are, for
diesel engines: the NMHC catalyst, the CDPF system, the
NOX adsorber system, the NOX converting
catalyst system, and the boost system; and, for gasoline engines:
the catalyst, the evaporative system, and the secondary air system;
and, for all engines, the exhaust gas sensors, the EGR system, and
the VVT system.
---------------------------------------------------------------------------
The numerator(s) would be defined as a measure of the number of
times a vehicle has been operated such that all monitoring conditions
necessary for a specific monitor to detect a malfunction have been
encountered. Except for systems using alternative statistical MIL
illumination protocols, the numerator is to be incremented by an
integer of one. The numerator(s) may not be incremented more than once
per drive cycle. The numerator(s) for a specific monitor would be
incremented within 10 seconds if and only if the following criteria are
satisfied on a single drive cycle:
Every monitoring condition necessary for the monitor of
the specific component to detect a malfunction and store a pending DTC
has been satisfied, including enable criteria, presence or absence of
related DTCs, sufficient length of monitoring time, and diagnostic
executive priority assignments (e.g., diagnostic ``A'' must execute
prior to diagnostic ``B''). For the purpose of incrementing the
numerator, satisfying all the monitoring conditions necessary for a
monitor to determine that the component is passing may not, by itself,
be sufficient to meet this criteria.
For monitors that require multiple stages or events in a
single drive cycle to detect a malfunction, every monitoring condition
necessary for all events to have completed must be satisfied.
For monitors that require intrusive operation of
components to detect a malfunction, a manufacturer would be required to
request Administrator approval of the strategy used to determine that,
had a malfunction been present, the monitor would have detected the
malfunction. Administrator approval of the request would be based on
the equivalence of the strategy to actual intrusive operation and the
ability of the strategy to determine accurately if every monitoring
condition was satisfied as necessary for the intrusive event to occur.
For the secondary air system monitor, the three criteria
above are satisfied during normal operation of the secondary air
system. Monitoring during intrusive operation of the secondary air
system later in the same drive cycle solely for the purpose of
monitoring may not, by itself, be sufficient to meet these criteria.
The third bullet item above requires explanation. There may be
monitors, and there have been monitors in light-duty, designed to use
what could be termed a two stage or two step process. The first step is
usually a passive and/or short evaluation that can be used to ``pass''
a properly working component where ``pass'' refers to evaluating the
component and determining that it is not malfunctioning. The second
step is usually an intrusive and/or longer evaluation that is necessary
to ``fail'' a malfunctioning component or ``pass'' a component nearing
the point of failure. An example of such an approach might be an
evaporative leak detection monitor that uses an intrusive vacuum pull-
down/bleed-up evaluation during highway cruise conditions. If the
evaporative system is sealed tight, the monitor ``passes'' and is done
with testing for the given drive cycle. If the monitor senses a leak
close to the required detection limit, the monitor does not ``pass''
and an internal flag is stored that will trigger the second stage of
the test during the next cold start when a more accurate evaluation can
be conducted. On the next cold start, provided the internal flag is
set, an intrusive vacuum pull-down/bleed up monitor might be conducted
during engine idle a very short time after the cold start. This second
evaluation stage, being at idle and cold, gives a more accurate
indication of the evaporative system's integrity and provides for a
more accurate decision regarding the presence and size of a leak.
In this example, the second stage of this monitor would run less
frequently in real use than the first stage since it is activated only
on those occasions where the first stage suggests that a leak may be
present (which most cars will not have). The rate-based tracking
requirements are meant to give a measure of how often a monitor could
detect a malfunction. To know the right answer, we need to know how
often the first stage is running and could ``fail'', thus triggering
the second stage, and then how often the second stage is completing. If
we track only the first stage, we would get a false indication of how
often the monitor could really detect a leak. But, if we track only the
second stage, most cars would never increment the counter since most
cars do not have leaks and would not trigger stage two.
In considering this, we see two possible solutions: (1) Always
activate the second stage evaluation in which case there would be an
intrusive monitor being performed that does not really need to be
performed; or, (2) implement a ``ghost'' monitor that pretends that the
first stage evaluation triggers the second stage evaluation and then
also looks for when the second stage evaluation could have completed
had it been necessary. The third bullet item in the list above requires
that, if a manufacturer intends to implement a two stage monitor and
intends to implement such a ``ghost'' monitor as described here for
rate based tracking, approval must be sought for doing so to make sure
we agree that you are doing it correctly and properly.
For monitors that can generate results in a ``gray zone'' or ``non-
detection zone'' (i.e., results that indicate neither a passing system
nor a malfunctioning system) or in a ``non-decision zone'' (e.g.,
monitors that increment and decrement counters until a pass or fail
threshold is reached), the manufacturer would be responsible for
incrementing the numerator appropriately. In general, the numerator
should not be incremented when the monitor indicates a result in the
``non-detection zone'' or prior to the monitor reaching a decision.
When necessary, the Administrator would consider data and/or
engineering analyses submitted by the manufacturer demonstrating the
expected frequency of results in the ``non-detection zone'' and the
ability of the monitor to determine accurately, had an actual
malfunction been present, whether or not the monitor would have
detected a malfunction instead of a result in the ``non-detection
zone.''
[[Page 3242]]
For monitors that run or complete their evaluation with the engine
off, the numerator must be incremented either within 10 seconds of the
monitor completing its evaluation in the engine off state, or during
the first 10 seconds of engine start on the subsequent drive cycle.
Manufacturers using alternative statistical MIL illumination
protocols for any of the monitors that require a numerator would be
required to increment the numerator(s) appropriately. The manufacturer
may be required to provide supporting data and/or engineering analyses
demonstrating both the equivalence of their incrementing approach to
the incrementing specified above for monitors using the standard MIL
illumination protocol, and the overall equivalence of their
incrementing approach in determining that the minimum acceptable in-use
performance ratio has been satisfied.
Regarding the denominator(s), defined as a measure of the number of
times a vehicle has been operated, we are proposing that it also be
incremented by an integer of one. The denominator(s) may not be
incremented more than once per drive cycle. The general denominator and
the denominators for each monitor would be incremented within 10
seconds if and only if the following criteria are satisfied on a single
drive cycle during which ambient temperature remained at or above 20
degrees Fahrenheit and altitude remained below 8,000 feet:
Cumulative time since the start of the drive cycle is
greater than or equal to 600 seconds (10 minutes);
Cumulative gasoline engine operation at or above 25 miles
per hour or diesel engine operation at or above 15 percent calculated
load, either of which occurs for greater than or equal to 300 seconds
(5 minutes); and
Continuous engine operation at idle (e.g., accelerator
pedal released by driver and vehicle speed less than or equal to one
mile per hour) for greater than or equal to 30 seconds.
In addition to the requirements above, the evaporative system
monitor denominator(s) must be incremented if and only if:
Cumulative time since the start of the drive cycle is
greater than or equal to 600 seconds (10 minutes) while at an ambient
temperature of greater than or equal to 40 degrees Fahrenheit but less
than or equal to 95 degrees Fahrenheit; and
Engine cold start occurs with engine coolant temperature
at engine start greater than or equal to 40 degrees Fahrenheit but less
than or equal to 95 degrees Fahrenheit and less than or equal to 12
degrees Fahrenheit higher than ambient temperature at engine start.
In addition to the requirements above, the denominator(s) for the
following monitors must be incremented if and only if the component or
strategy is commanded ``on'' for a time greater than or equal to 10
seconds:
Gasoline secondary air system;
Cold start emission reduction strategy;
Components or systems that operate only at engine start-up
(e.g., glow plugs, intake air heaters) and are subject to monitoring
under ``other emission control systems'' (section II.D.5) or
comprehensive component output components (see section II.D.4).
For purposes of determining this commanded ``on'' time, the OBD
system may not include time during intrusive operation of any of the
components or strategies later in the same drive cycle solely for the
purposes of monitoring.
In addition to the requirements above, the denominator(s) for the
monitors of the following output components (except those operated only
at engine start-up as outlined above) must be incremented if and only
if the component is commanded to function (e.g., commanded ``on'',
``open'', ``closed'', ``locked'') two or more times during the drive
cycle or for a time greater than or equal to 10 seconds, whichever
occurs first:
Variable valve timing and/or control system
``Other emission control systems''
Comprehensive component (output component only, e.g.,
turbocharger waste-gates, variable length manifold runners)
For monitors of the following components, the manufacturer may use
alternative or additional criteria to that set forth above for
incrementing the denominator. To do so, the manufacturer would need to
be able to demonstrate that the criteria would be equivalent to the
criteria outlined above at measuring the frequency of monitor operation
relative to the amount of engine operation:
Engine cooling system input components (section II.D.2)
``Other emission control systems'' (section II.D.5)
Comprehensive component input components that require
extended monitoring evaluation (section II.D.4, e.g., stuck fuel level
sensor rationality)
For monitors of the following components or other emission controls
that experience infrequent regeneration events, the manufacturer may
use alternative or additional criteria to that set forth above for
incrementing the denominator. To do so, the manufacturer would need to
demonstrate that the criteria would be equivalent to the criteria
outlined above at measuring the frequency of monitor operation relative
to the amount of engine operation:
Oxidation catalysts
Diesel particulate filters
For hybrid engine systems, engines that employ alternative engine
start hardware or strategies (e.g., integrated starter and generators),
or alternative fueled engines (e.g., dedicated, bi-fuel, or dual-fuel
applications), the manufacturer may request Administrator approval to
use alternative criteria to that set forth above for incrementing the
denominator. In general, approval would not be given for alternative
criteria that only employ engine shut off at or near idle/vehicle
stationary conditions. Approval of the alternative criteria would be
based on the equivalence of the alternative criteria at determining the
amount of engine operation relative to the measure of conventional
engine operation in accordance with the criteria above.
The numerators and denominators may need to be disabled at some
times. To do this, within 10 seconds of a malfunction being detected
(i.e., a pending, MIL-on, or active DTC being stored) that disables a
monitor required to meet the performance tracking requirements,\45\ the
OBD system must disable further incrementing of the corresponding
numerator and denominator for each monitor that is disabled. When the
malfunction is no longer detected (e.g., the pending DTC is erased
through self-clearing or through a scan tool command), incrementing of
all corresponding numerators and denominators should resume within 10
seconds. Also, within 10 seconds of the start of a power takeoff unit
(PTO) that disables a monitor required to meet the performance tracking
requirements, the OBD system should disable further incrementing of the
corresponding numerator and denominator for each monitor that is
disabled. When the PTO operation ends, incrementing of all
corresponding numerators and denominators should resume within 10
seconds. The OBD system must disable further incrementing of all
numerators
[[Page 3243]]
and denominators within 10 seconds if a malfunction has been detected
in any component used to determine if: vehicle speed/calculated load;
ambient temperature; elevation; idle operation; engine cold start; or,
time of operation has been satisfied, and the corresponding pending DTC
has been stored. Incrementing of all numerators and denominators should
resume within 10 seconds when the malfunction is no longer present
(e.g., pending DTC erased through self-clearing or by a scan tool
command).
---------------------------------------------------------------------------
\45\ These monitors, as presented in section II.A.3, are, for
diesel engines: the NMHC catalyst, the CDPF system, the
NOX adsorber system, the NOX converting
catalyst system, and the boost system; and, for gasoline engines:
the catalyst, the evaporative system, and the secondary air system;
and, for all engines, the exhaust gas sensors, the EGR system, and
the VVT system.
---------------------------------------------------------------------------
The in-use performance monitoring ratio itself is defined as the
numerator for the given monitor divided by the denominator for that
monitor.
b. Standardized Tracking and Reporting of Monitor Performance
We are proposing that the OBD system separately report an in-use
monitor performance numerator and denominator for each of the following
components:
For diesel engines: NMHC catalyst bank 1, NMHC catalyst
bank 2, NOX catalyst bank 1, NOX catalyst bank 2,
exhaust gas sensor bank 1, exhaust gas sensor bank 2, EGR/VVT system,
DPF system, turbo boost control system, and the NOX
adsorber. The OBD system must also report a general denominator and an
ignition cycle counter in the standardized format discussed below and
in section II.F.5.
For gasoline engines: catalyst bank 1, catalyst bank 2,
oxygen sensor bank 1, oxygen sensor bank 2, evaporative leak detection
system, EGR/VVT system, and secondary air system. The OBD system must
also report a general denominator and an ignition cycle counter in the
standardized format specified below and in section II.F.5.
The OBD system would be required to report a separate numerator for
each of the components listed in the above bullet lists. For specific
components or systems that have multiple monitors that are required to
be reported under section II.B--e.g., exhaust gas sensor bank 1 may
have multiple monitors for sensor response or other sensor
characteristics--the OBD system should separately track numerators and
denominators for each of the specific monitors and report only the
corresponding numerator and denominator for the specific monitor that
has the lowest numerical ratio. If two or more specific monitors have
identical ratios, the corresponding numerator and denominator for the
specific monitor that has the highest denominator should be reported
for the specific component. The numerator(s) must be reported in
accordance with the specifications in section II.F.5.
The OBD system would also be required to report a separate
denominator for each of the components listed in the above bullet
lists. The denominator(s) must be reported in accordance with the
specifications in section II.F.5.
Similarly, for the in-use performance ratio, determining which
corresponding numerator and denominator to report as required for
specific components or systems that have multiple monitors that are
required to be reported--e.g., exhaust gas sensor bank 1 may have
multiple monitors for sensor response or other sensor
characteristics'the ratio should be calculated in accordance with the
specifications in section II.F.5.
The ignition cycle counter is defined as a counter that indicates
the number of ignition cycles a vehicle has experienced. The ignition
cycle counter must also be reported in accordance with the
specifications in section II.F.5. The ignition cycle counter, when
incremented, should be incremented by an integer of one. The ignition
cycle counter may not be incremented more than once per ignition cycle.
The ignition cycle counter should be incremented within 10 seconds if
and only if the engine exceeds an engine speed of 50 to 150 rpm below
the normal, warmed-up idle speed (as determined in the drive position
for vehicles equipped with an automatic transmission) for at least two
seconds plus or minus one second. The OBD system should disable further
incrementing of the ignition cycle counter within 10 seconds if a
malfunction has been detected in any component used to determine if
engine speed or time of operation has been satisfied and the
corresponding pending DTC has been stored. The ignition cycle counter
may not be disabled from incrementing for any other condition.
Incrementing of the ignition cycle counter should resume within 10
seconds after the malfunction is no longer present (e.g., pending DTC
erased through self-clearing or by a scan tool command).
F. Standardization Requirements
The heavy-duty OBD regulation would include requirements for
manufacturers to standardize certain features of the OBD system.
Effective standardization assists all repair technicians in diagnosing
and repairing malfunctions by providing equal access to essential
repair information, and requires structuring the information in a
common format from manufacturer to manufacturer. Additionally, the
standardization would help to facilitate the potential use of OBD
checks in heavy-duty inspection and maintenance programs.
Among the features that would be standardized under the proposed
heavy-duty OBD regulation include:
The diagnostic connector, the computer communication
protocol;
The hardware and software specifications for tools used by
service technicians;
The information communicated by the onboard computer and
the methods for accessing that information;
The numeric designation of the DTCs stored when a
malfunction is detected; and,
The terminology used by manufacturers in their service
manuals.
Our proposal would require that only a certain minimum set of
emissions-related information be made available through the
standardized format, protocol, and connector. We are not limiting
engine manufacturers as to what protocol they use for engine control,
communication between onboard computers, or communication to
manufacturer-specific scan tools or test equipment. Further, we are not
prohibiting engine manufacturers from equipping the vehicle with
additional diagnostic connectors or protocols as required by other
suppliers or purchasers. For example, fleets that use data logging or
other equipment that requires the use of SAE J1587 communication and
connectors could still be installed and supported by the engine and
vehicle manufacturers. The OBD rules would only require that engine
manufacturers also equip their vehicles with a specific connector and
communication protocol that meet the standardized requirements to
communicate a minimum set of emissions-related diagnostic, service and,
potentially, inspection information.
Additionally, our proposal includes a phase-in of one engine family
meeting the requirements of OBD in the model years 2010 through 2012.
Because non-compliant engines would not require the proposed
standardization features, truck and coach builders could be faced with
several integration issues when building product in 2010 through 2012.
Specifically, they could be faced with designing their vehicles to
accommodate a standardized MIL, diagnostic connector, and communication
protocol when using a compliant engine yet to not accommodate those
features when using a non-compliant engine. This outcome could easily
arise since only one engine-family per manufacturer would be compliant
and, therefore, a given truck
[[Page 3244]]
designed to accommodate several engines from several engine
manufacturers would very likely need to accommodate a compliant engine
from manufacturer A and a non-compliant engine from manufacturer B. It
should be noted that engine choices are typically driven by the end
user--the truck buyer--and not by the truck or coach builder. For that
reason, the truck builder must accommodate all possible engines for the
truck size and cannot necessarily demand from the engine manufacturer a
compliant versus a non-compliant engine.
As a result, rather than force truck and coach builders to
accommodate two different systems and risk incompatibilities, we are
proposing to exempt the 2010 through 2012 model year engines from
meeting certain standardization requirements of OBD. This should allow
truck and coach builders to integrate engines in the same manner as
done currently and then to switch over to integrating a single system
in 2013 when all engines are required to meet all of the
standardization requirements of OBD. The proposed implementation
schedule for standardization features is shown in Table II.G-2.
1. Reference Documents
We are proposing that OBD systems comply with the following
provisions laid out in the following Society of Automotive Engineers
(SAE) and/or International Organization of Standards (ISO) documents
that are or would be incorporated by reference (IBR) into federal
regulation:
Table II.F--1. Reference Documents for Over 14,000 Pound OBD
----------------------------------------------------------------------------------------------------------------
Document No. Document title Date Comment
----------------------------------------------------------------------------------------------------------------
SAE J1962................. ``Diagnostic Connector--Equivalent April 2002.......... Updated IBR.
to ISO/DIS 15031-3: December 14,
2001''.
SAE J1930................. ``Electrical/Electronic Systems April 2002.......... Updated IBR.
Diagnostic Terms, Definitions,
Abbreviations, and Acronyms--
Equivalent to ISO/TR 15031-2:
April 30, 2002''.
SAE J1978................. ``OBD II Scan Tool--Equivalent to April 2002.......... Updated IBR.
ISO/DIS 15031-4: December 14,
2001''.
SAE J1979................. ``E/E Diagnostic Test Modes-- April 2002.......... Updated IBR.
Equivalent to ISO/DIS 15031-5:
April 30, 2002''.
SAE J2012................. ``Diagnostic Trouble Code April 2002.......... Updated IBR.
Definitions--Equivalent to ISO/DIS
15031-6: April 30, 2002''.
SAE J1939................. ``Recommended Practice for a Serial 2005 Edition, March Updated IBR.
Control and Communications Vehicle 2005.
Network,'' and the associated
subparts included in SAE HS-1939,
``Truck and Bus Control and
Communications Network Standards
Manual''.
SAE J2403................. ``Medium/Heavy-Duty E/E Systems August 2004......... New IBR.
Diagnosis Nomenclature''.
SAE J2534................. ``Recommended Practice for Pass- February 2002....... New IBR.
Thru Vehicle Reprogramming''.
ISO 15765-4:2001.......... ``Road Vehicles--Diagnostics on December 2001....... New IBR.
Controller Area Network (CAN)--
Part 4: Requirements for emission-
related systems''.
----------------------------------------------------------------------------------------------------------------
Copies of these SAE materials may be obtained from Society of
Automotive Engineers International, 400 Commonwealth Dr., Warrendale,
PA, 15096-0001. Copies of these ISO materials may be obtained from the
International Organization for Standardization, Case Postale 56, CH-
1211 Geneva 20, Switzerland.
2. Diagnostic Connector Requirements
We are proposing that a standard data link connector conforming to
either SAE J1962 or SAE J1939-13 specifications (except as noted below)
would have to be included in each vehicle. The connector would have to
be located in the driver's side foot-well region of the vehicle
interior in the area bound by the driver's side of the vehicle and the
driver's side edge of the center console (or the vehicle centerline if
the vehicle does not have a center console) and at a location no higher
than the bottom of the steering wheel when in the lowest adjustable
position. The Administrator would not allow the connector to be located
on or in the center console (i.e., neither on the horizontal faces near
the floor-mounted gear selector, parking brake lever, or cup-holders,
nor on the vertical faces near the car stereo, climate system, or
navigation system controls). The location of the connector must be
easily identifiable and accessed (e.g., to connect an off-board tool).
For vehicles equipped with a driver's side door, the connector would
have to be easily identified and accessed by someone standing (or
``crouched'') on the ground outside the driver's side of the vehicle
with the driver's side door open.
If a manufacturer wants to cover the connector, the cover must be
removable by hand without the use of any tools and be labeled ``OBD''
to aid technicians in identifying the location of the connector. Access
to the diagnostic connector could not require opening or removing any
storage accessory (e.g., ashtray, coinbox). The label would have to
clearly identify that the connector is located behind the cover and is
consistent with language and/or symbols commonly used in the automobile
and/or heavy truck industry.
If the ISO 15765-4 protocol (see section II.F.3) is used for the
required OBD standardized functions, the connector would have to meet
the ``Type A'' specifications of SAE J1962. Any pins in the connector
that provide electrical power must be properly fused to protect the
integrity and usefulness of the connector for diagnostic purposes and
may not exceed 20.0 Volts DC regardless of the nominal vehicle system
or battery voltage (e.g., 12V, 24V, 42V).
If the SAE J1939 protocol (see section II.F.3)) is used for the
required OBD standardized functions, the connector must meet the
specifications of SAE J1939-13. Any pins in the connector that provide
electrical power must be properly fused to protect the integrity and
usefulness of the connector for diagnostic purposes.
Manufacturers would be allowed to equip engines/vehicles with
additional diagnostic connectors for manufacturer-specific purposes
(i.e., purposes other than the required OBD functions). However, if the
additional connector conforms to the ``Type A'' specifications of SAE
J1962 or the specifications of SAE J1939-13 and is located in the
vehicle interior near the required connector as described above, the
connector(s) must be clearly labeled to identify which connector is
used to access the standardized OBD information proposed below.
[[Page 3245]]
3. Communications to a Scan Tool
a. Background
In light-duty OBD, manufacturers are allowed to use one of four
protocols for communication between a generic scan tool and the
vehicle's onboard computer. A generic scan tool automatically cycles
through each of the allowable protocols until it hits upon the proper
one with which to establish communication with the particular onboard
computer. While this has generally worked successfully in the field,
some communication problems have arisen.
In an effort to address these problems, CARB has made recent
changes to their light-duty OBD II regulation that require all light-
duty vehicle manufacturers to use only one communication protocol by
the 2008 model year. In making these changes, CARB staff argued that
their experience with standardization under the OBD II regulation
showed that having a single set of standards used by all vehicles would
be desirable. CARB staff argued that a single protocol offers a
tremendous benefit to both scan tool designers and service technicians.
Scan tool designers could focus on added feature content and could
expend much less time and money validating basic functionality of their
product on all the various permutations of protocol interpretations
that are implemented. In turn, technicians would likely get a scan tool
that works properly on all vehicles without the need for repeated
software updates that incorporate ``work-arounds'' or other patches to
fix bugs or adapt the tool to accommodate slight variances in how the
multiple protocols interact with each other or are implemented by
various manufacturers. Further, a single protocol should also be
beneficial to fleet operators that use add-on equipment such as data
loggers, and for vehicle manufacturers that integrate parts from
various engine and component suppliers all of which must work together.
Based on our similar experiences at the federal level with
communication protocols giving rise to service and inspection/
maintenance program issues, we initially wanted to propose a single
communication protocol for engines used in over 14,000 pound vehicles.
However, the affected industry has been divided over which single
protocol should be required and has strongly argued for more than one
protocol to be allowed. Therefore, for vehicles with diesel engines, we
are proposing that manufacturers be required to use either the
standards set forth in SAE J1939, or those set forth in the 500 kbps
baud rate version of ISO 15765. For vehicles with gasoline engines, we
are proposing that manufacturers be required to use the 500 kbps baud
rate version of ISO 15765. Manufacturers would be required to use only
one standard to meet all the standardization requirements on a single
vehicle; that is, a vehicle must use only one protocol for all OBD
modules on the vehicle.
Several in the heavy-duty industry have argued for options that
would allow the use of more than these two protocols on heavy-duty
engines. Some have even argued for combinations of these protocols--
e.g., diagnostic connector and messages of ISO 15765 on an SAE J1939
physical layer network. However, as described above, experience from
multiple protocols and multiple variants within the protocols has
unnecessarily caused a significant number of problems with engine and
vehicle related computer communications.
b. Requirements for Communications to a Scan Tool
We are proposing that all OBD control modules--e.g., engine,
auxiliary emission control module--on a single vehicle be required to
use the same protocol for communication of required emissions-related
messages from onboard to off-board network communications to a scan
tool meeting SAE J1978 specifications or designed to communicate with a
SAE J1939 network. Engine manufacturers would not be allowed to alter
normal operation of the engine emissions control system due to the
presence of off-board test equipment accessing the OBD information
proposed below. The OBD system would be required to use one of the
following standardized protocols:
ISO 15765-4 and all required emission-related messages
using this protocol would have to use a 500 kbps baud rate.
SAE J1939 which may only be used on vehicles with diesel
engines.
4. Required Emissions Related Functions
Most of the proposed emissions related functions are elements that
exist in our light-duty OBD requirements. We are proposing several
required functions, these are:
Readiness status
Distance and number of warm-up cycles since DTC clear
Permanent DTC storage
Real time indication of monitor status
Communicating readiness status to the vehicle operator
Diagnostic trouble codes (DTC)
Data stream
Freeze frame
Test results
Software calibration identification
Software calibration verification number
Vehicle identification number (VIN)
i. Readiness Status
The main intent of readiness status is to ensure that a vehicle is
ready for an OBD-based inspection--by indicating that monitors have run
and operational status of the emissions-control system has been fully
evaluated--and to prevent fraudulent testing in inspection programs. In
general, for OBD-based inspections, technicians ``fail'' a vehicle with
an illuminated MIL since this would indicate the presence of an
emissions control system malfunction. Without the readiness status
indicators, technicians would not have a clear indication from the OBD
system that it had sufficiently evaluated the emissions control system
prior to the inspection. Since the potential exists for OBD checks to
be used as part of a heavy truck inspection program, we believe that
having readiness status indicators as part of this proposal is
important--waiting for a subsequent OBD-I/M rulemaking to require such
indicators would unnecessarily delay implementation of such OBD-I/M
programs.
Absent such OBD-I/M programs, we still believe that readiness
indicators are an important OBD tool. Technicians would be expected to
use the readiness status to verify OBD-related repairs. Specifically,
technicians would clear the computer memory after repairing an OBD-
detected fault in order to erase the DTC, extinguish the MIL, and reset
the readiness status to ``incomplete.'' Then the vehicle could be
operated in such a manner that the monitor of the repaired component
would run (i.e., the readiness status of the monitor would be set to
``complete''). The absence of any DTCs or MIL illumination upon
readiness status indicating ``complete'' would indicate a successful
repair.
Therefore, we are proposing that manufacturers be required to
indicate the readiness status of the OBD monitors. This would serve to
indicate whether or not engine operation has been sufficient to allow
certain OBD monitors to perform their system evaluations. The OBD
system would be required to report a readiness status of either
``complete'' if the monitor has run a sufficient number of times to
detect a malfunction since computer memory was last cleared,
``incomplete'' if the monitor has not yet run a sufficient number of
times since the memory was last cleared, or ``not applicable'' if the
[[Page 3246]]
monitor is not present or if the specific monitored component is not
equipped on the vehicle. The readiness status of monitors that are
required to run continuously would always indicate ``complete.'' The
details of the proposal discussed below clarify that the readiness
status would be set to ``incomplete'' whenever memory is cleared either
by a battery disconnect or by a scan tool but not after a normal
vehicle shutdown (i.e., key-off).
ii. Distance Traveled and Number of Warm-Up Cycles Since DTC Clear
As originally envisioned in our OBD-I/M rulemaking (61 FR 40940),
we intended to require that all readiness status indicators be set to
``complete'' prior to accepting a vehicle for I/M inspection. However,
it became clear that some vehicles were being rejected from inspection
for reasons beyond the driver's control. For example, a vehicle driven
in extreme ambient conditions would prohibit monitors from running and
setting readiness status indicators to ``complete.'' Also, a vehicle
repaired just prior to arriving at the inspection station may not have
been operated sufficiently to set the readiness status of the monitor
for the recently repaired component to ``complete.'' The driver of such
a vehicle would, in essence, be punished unintentionally for having
taken the time and expense to repair the vehicle just prior to the
inspection. As a result, we issued guidance (cite) to state inspectors
recommending that vehicles be accepted for I/M inspection provided two
or fewer readiness status indicators are ``incomplete.'' Note that most
light-duty gasoline vehicles--the bulk of the vehicle fleet facing OBD-
I/M checks--have only four monitors for which the readiness status
indicator is meaningful (all of their other monitors being continuous
monitors). However, there exists evidence that this policy is perhaps
accepting vehicles for I/M inspection that should not be accepted due
to unscrupulous clearing of DTCs and readiness status by people that
understand how to do so and then operate their vehicles just enough to
set the required minimum number of readiness indicators to
``complete.''
As a result, we are proposing some additional features that should
better differentiate between vehicles that have been repaired recently
or have ``incomplete'' readiness indicators through circumstances
outside the driver's control, and those vehicles operated by drivers
that are attempting to fraudulently get through an OBD-based
inspection. We are proposing that the OBD system make available data
that would report the distance traveled or engine run time for those
engines that do not use vehicle speed information, and the number of
warm-up cycles since the fault memory was last cleared.\46\ By
combining these data with the readiness data, technicians or inspectors
would better be able to determine if ``incomplete'' readiness status
indicators or an extinguished MIL are due to unscrupulous memory
clearing or circumstances beyond the driver's control. For example, a
vehicle with several ``incomplete'' readiness indicators but with a
high distance traveled/engine run time and a high number of warm-up
cycles since the last clearing of fault memory would be unlikely to
have undergone a recent fault memory clearing for the purpose of
extinguishing the MIL prior to inspection. On the other hand, a vehicle
with only one or two ``incomplete'' readiness indicators and a very low
distance traveled/engine run time and a low number of warm-up cycles
since fault memory clearing should probably be rejected or failed at an
inspection. This would better allow an inspection program to be set up
to reject only those vehicles with recently cleared memories while
minimizing the chances of rejecting vehicles that driven such that
monitors rarely run whether by unique driver behaviors or extreme
ambient conditions.
---------------------------------------------------------------------------
\46\ The fault memory being any DTCs, readiness status
indicators, freeze frame information, etc.
---------------------------------------------------------------------------
iii. Permanent Diagnostic Trouble Code Storage
Consistent with the proposal for distance traveled/engine run time
and number of warm-up cycles, we are proposing a requirement to make it
much more difficult for a vehicle owner or technician to clear the
fault memory and erase all traces of a previously detected malfunction.
Current OBD systems on under 14,000 pound vehicles allow a technician
or vehicle owner to erase all DTCs and extinguish the MIL by issuing a
command from a generic scan tool or, in many cases, simply by
disconnecting the vehicle battery. This would set to ``incomplete'' the
readiness status indicators for all monitors and would remove all
record of the malfunction that had been detected.
We are proposing that manufacturers be required to store in non-
volatile memory random access memory (NVRAM) a minimum of four MIL-on
DTCs that are, at present, commanding the MIL-on. These ``permanent''
DTCs would have to be stored in NVRAM at the end of every key cycle. By
requiring these permanent DTCs to be stored in NVRAM, one would not be
able to erase them simply by disconnecting the battery. Further,
manufacturers would not be allowed to design their OBD systems such
that these permanent DTCs could be erased by any generic or
manufacturer-specific scan tool command. Instead, the permanent DTCs
could be erased only via an OBD system self-clearing--i.e., upon
evaluating the component or system for which the permanent DTC has been
stored and detecting on sufficient drive cycles that the malfunction is
no longer present, the OBD system would erase the fault memory as
discussed in section II.A.2. Once this has occurred, the permanent DTC
stored in NVRAM would be erased also.
The permanent DTCs should help if states choose to implement OBD-
based I/M programs for heavy trucks. A truck with readiness status
indicators for EGR and boost control set to ``incomplete'' and with
permanent DTCs stored for both EGR and boost control would quite
probably be a truck that should be rejected from inspection. The OBD
system on such a truck has almost certainly had its fault memory
cleared--via scan tool command or battery disconnect--which would set
the readiness indicators to ``incomplete'' and erase all MIL-on DTCs
but would still have permanent DTCs stored (only the OBD system itself
can erase permanent DTCs). Likewise, a truck with the same readiness
indicators set to ``incomplete'' and no permanent DTCs for those
monitors should almost certainly be accepted for inspection since the
lack of readiness is almost certainly due to circumstances outside the
driver's control.
We believe that the permanent DTCs also provide advantages to
technicians attempting to repair a malfunction and prepare it for
subsequent inspection or proof of correction. The permanent DTC would
identify the specific monitor that would need to be exercised after
repair and prior to inspection to be sure that the malfunction has been
repaired. By combining this information with the vehicle manufacturer's
service information, technicians could identify the exact conditions
necessary to exercise the particular monitor. As such, technicians
could more effectively verify that the specific monitor (that monitor
having illuminated the MIL for which the repair has been done) has run
and confirmed that the malfunction no longer exists and the repair has
been made correctly. This should also reduce vehicle owner ``come-
backs'' for incomplete or ineffective repairs.
[[Page 3247]]
iv. Real Time Indication of Monitor Status
We are also proposing provisions to make it easier for technicians
to prepare a vehicle for an inspection following a repair. These
provisions would require that the OBD system provide real time data
that indicate whether the necessary conditions are present currently to
set all of the readiness indicators to ``complete.'' These data would
indicate whether a particular monitor may still have an opportunity to
run on the current drive cycle or whether a condition has been
encountered that has disabled the monitor for the rest of the drive
cycle regardless of the driving conditions that might be encountered.
While these data would not provide technicians with the exact
conditions necessary to exercise the monitors (only service information
would provide such information), the date in combination with the
service information should assist technicians in verifying repairs and/
or preparing a vehicle for inspection. Technicians would be able to use
this information to identify when specific monitors have indeed
completed or to identify situations where they have overlooked one or
more of the enable criteria and need to check the service information
and try again.
v. Communicating Readiness Status to the Vehicle Operator
As mentioned above, substantial feedback has been received from
OBD-based I/M programs throughout the U.S. Much of this feedback
pertains to the effect on vehicle owners caused by being rejected from
I/M inspection due to ``incomplete'' readiness status indicators. To
address this, some light-duty vehicle manufacturers requested that they
be allowed to communicate the vehicle's readiness status to the vehicle
owner directly without need of a scan tool. This would provide
assurance to the vehicle owner that their vehicle is ready for
inspection prior to taking the vehicle to the I/M station. We are
proposing that heavy-duty engine manufacturers be allowed to do the
same thing (this is a proposed option, not a proposed requirement). If
a manufacturer chooses to implement this option, though, they would be
required to do so in a standardized manner. On engines equipped with
this option, the owner would be able to initiate a self-check of the
readiness status, thereby greatly reducing the possibility of being
rejected at a roadside inspection.
vi. Diagnostic Trouble Codes (DTC)
Malfunctions are reported by the OBD system and displayed on a scan
tool for service technicians in the form of diagnostic trouble codes
(DTCs). We are proposing that manufacturers be required to report all
emissions-related DTCs using a standardized format and to make them
accessible to all service technicians, including the independent
service industry. The reference document standards selected by the
manufacturer would define many generic DTCs to be used by all
manufacturers. In the rare circumstances that a manufacturer cannot
find within the reference documents a suitable DTC, a unique
``manufacturer-specific'' DTC could be used. However, such
manufacturer-specific DTCs are not as easily interpreted by the
independent service industry. Excessive use of manufacturer-specific
DTCs may increase the time and cost for vehicle repairs. Thus, we are
proposing to restrict the use of manufacturer-specific DTCs. If a
generic DTC suitable for a given malfunction cannot be found, the
manufacturer would be expected to pursue approval and addition of
appropriate generic DTCs into the reference documents; the intent being
to standardize as much information as possible.
Additionally, we are proposing that the OBD system store DTCs that
are as specific as possible to identify the nature of the malfunction.
The intent being to provide service technicians with as detailed
information as possible to diagnose and repair vehicles in an efficient
manner. In other words, manufacturers should use separate DTCs for
every monitor where the monitor and repair procedure, or likely cause
of the failure, is different. Generally, a manufacturer would design an
OBD monitor that detects different root causes (e.g., sensor shorted to
ground or battery) for a malfunctioning component or system. We would
expect manufacturers to store a specific DTC such as ``sensor circuit
high input'' or ``sensor circuit low input'' rather than a general code
such as ``sensor circuit malfunction.'' Further, we expect
manufacturers to store different DTCs that distinguish circuit
malfunctions from rationality and functional malfunctions since the
root cause for each is different and, thus, the repair procedures may
be different.
We are also proposing specific provisions for storage of pending
and MIL-on DTCs. These proposed provisions were discussed in section
II.A.2.
We are also proposing requirements that would help to distinguish
between DTCs stored for malfunctions that are currently present and for
malfunctions that are no longer present. These requirements would apply
only to those engines using ISO 15765-4 as the communication protocol.
As described in section II.A.2, the OBD system would generally
extinguish the MIL if the malfunction responsible for the MIL
illumination has not been detected (i.e., the monitor runs and
determines that the malfunction no longer exists) on three subsequent
sequential drive cycles. However, a manufacturer would not be allowed
to erase the associated MIL-on DTC until 40 engine warm-up cycles have
occurred without again detecting the malfunction. So even though the
malfunction is no longer present and a MIL-on is not being commanded,
the DTC would still remain (termed a ``history'' code in the ISO
standard). Consequently, if another unrelated malfunction occurs and
results in a MIL-on, a new DTC would be stored along with the history
DTC. When trying to diagnose the OBD problem, technicians accessing DTC
information may have trouble distinguishing which DTC is responsible
for illuminating the MIL (i.e., which malfunction is present
currently), and thus could have trouble determining what exactly must
be repaired. Therefore, we are proposing this requirement for ISO
engines to help distinguish between DTCs stored for malfunctions that
are present and those that were present. Note that, for engines using
SAE J1939 as the communication protocol, such a distinction is already
provided for.
Permanent DTCs would also need to be separately identified from the
other types of DTCs. Additionally, as described above, manufacturers
would be required to develop additional software routines to store and
erase permanent DTCs in NVRAM and to prevent erasure from any battery
disconnect or scan tool command.
vii. Data Stream/Freeze Frame/Test Results
An important aspect of OBD is the ability of technicians to access
critical information from the onboard computer to diagnose and repair
emissions-related malfunctions. We believe that having access through
the diagnostic connector to real-time electronic information regarding
certain emissions critical components and systems would provide
valuable assistance for repairing vehicles properly. The availability
of real-time information would also provide assistance to technicians
[[Page 3248]]
responding to drivability complaints since the vehicle could be
operated within the necessary operating conditions and the technician
could see how various sensors and systems were acting. Similarly, fuel
economy complaints, loss of performance complaints, intermittent
problems, and others issues could also be addressed.
We are proposing a number of data parameters that the OBD system
would be required to report to a generic scan tool. These parameters,
which would include information such as engine speed and exhaust gas
sensor readings, would allow technicians to understand how the vehicle
engine control system is functioning, either as the vehicle operates in
a service bay or during actual driving. They would also help
technicians diagnose and repair emission-related malfunctions by
allowing them to watch instantaneous changes in the values while
operating the vehicle.
Some of the data parameters we are proposing are intended to assist
us in performing in-use testing of heavy-duty engines for compliance
with emissions standards. One of the parameters that manufacturers
would be required to report is the real-time status of the
NOX and PM ``not-to-exceed'' (NTE) control areas. The NTE
standards define a wide range of engine operating points where a
manufacturer must design the engine to be below a maximum emission
level. In theory, whenever the engine is operated within the speed and
load region defined as the NTE zone, emissions will be below the
required standards. However, within the NTE zone, manufacturers are
allowed, if justified on a case-by-case basis, to either modify the
time frame in which the standard must be met, and in the second case to
be exempted from the emission standards under specific conditions
(e.g., an NTE deficiency). Manufacturers can request two types of
modifications: first, a five percent limited testing region within
which no more than five percent of in-use operation is expected to
occur and, thus, no more than five percent of NTE emissions sampling
within that region can be compared to the NTE standard for a given
sampling event; and second, NTE deficiencies which are precisely
defined exemption conditions where compliance cannot be met due to
technical reasons or for engine protection. These regions and
conditions can be defined by directly measured signals or, in some
cases, by complicated modeled values calculated internally in the
engine computer. When conducting emissions testing of these engines,
knowing if the engine is inside the NTE zone--and subject to the NTE
standards--or is outside of the NTE zone or, perhaps, in an NTE limited
testing region or covered by an NTE deficiency is imperative. As our
in-use testing program requirements are written currently, we must post
process data to determine which data points were generated within a
compliance zone and which were generated within an exempted zone. Such
post processing, while possible, is inefficient, time consuming, and
resource intensive. Having the NTE zone data broadcast in real-time
over the engine's network would allow for a much more efficient use of
our resources.
The specific parameters we are proposing for inclusion in the data
stream are, for gasoline engines: calculated load value, engine coolant
temperature, engine speed, vehicle speed, time elapsed since engine
start, absolute load, fuel level (if used to enable or disable any
other monitors), barometric pressure (directly measured or estimated),
engine control module system voltage, commanded equivalence ratio,
number of stored MIL-on DTCs, catalyst temperature (if directly
measured or estimated for purposes of enabling the catalyst
monitor(s)), monitor status (i.e., disabled for the rest of this drive
cycle, complete this drive cycle, or not complete this drive cycle)
since last engine shut-off for each monitor used for readiness status,
distance traveled/engine run time with a commanded MIL-on, distance
traveled/engine run time since fault memory last cleared, number of
warm-up cycles since fault memory last cleared, OBD requirements to
which the engine is certified (e.g., California OBD, EPA OBD, non-OBD)
and MIL status (i.e., commanded-on or commanded-off). And, for diesel
engines: calculated load (engine torque as a percentage of maximum
torque available at the current engine speed),\47\ driver's demand
engine torque (as a percentage of maximum engine torque), actual engine
torque (as a percentage of maximum engine torque), reference engine
maximum torque, reference maximum engine torque as a function of engine
speed (suspect parameter numbers (SPN) 539 through 543 defined in SAE
J1939 within parameter group number (PGN) 65251 for engine
configuration), engine coolant temperature, engine oil temperature (if
used for emission control or any OBD monitors), engine speed, time
elapsed since engine start, fuel level (if used to enable or disable
any other diagnostics), vehicle speed (if used for emission control or
any OBD monitors), barometric pressure (directly measured or
estimated), engine control module system voltage, number of stored MIL-
on DTCs, monitor status (i.e., disabled for the rest of this drive
cycle, complete this drive cycle, or not complete this drive cycle)
since last engine shut-off for each monitor used for readiness status,
distance traveled/engine run time with a commanded MIL-on, distance
traveled/engine run time since fault memory last cleared, number of
warm-up cycles since DTC memory last cleared, OBD requirements to which
the engine is certified (e.g., EPA OBD parent rating, EPA OBD child
rating, non-OBD), and MIL status (i.e., commanded-on or commanded-off).
Also for diesel engines, as discussed above, separate NOX
and PM NTE control area status (i.e., inside control area, outside
control area, inside manufacturer-specific NTE carve-out area, or
deficiency active area). Also, for all engines so equipped (and only
those so equipped): absolute throttle position, relative throttle
position, fuel control system status (e.g., open loop, closed loop),
fuel trim, fuel pressure, ignition timing advance, fuel injection
timing, intake air/manifold temperature, engine intercooler
(aftercooler) temperature, manifold absolute pressure, air flow rate
from mass air flow sensor, secondary air status (upstream, downstream,
or atmosphere), ambient air temperature, commanded purge valve duty
cycle/position, commanded EGR valve duty cycle/position, actual EGR
valve duty cycle/position, EGR error between actual and commanded, PTO
status (active or not active), redundant absolute throttle position
(for electronic throttle or other systems that utilize two or more
sensors), absolute pedal position, redundant absolute pedal position,
commanded throttle motor position, fuel rate, boost pressure,
commanded/target boost pressure, turbo inlet air temperature, fuel rail
pressure, commanded fuel rail pressure, DPF inlet pressure, DPF inlet
temperature, DPF outlet pressure, DPF outlet temperature, DPF delta
pressure, exhaust pressure sensor output, exhaust gas temperature
sensor output, injection control pressure, commanded injection control
pressure, turbocharger/turbine speed,
[[Page 3249]]
variable geometry turbo position, commanded variable geometry turbo
position, turbocharger compressor inlet temperature, turbocharger
compressor inlet pressure, turbocharger turbine inlet temperature,
turbocharger turbine outlet temperature, wastegate valve position, glow
plug lamp status, oxygen sensor output, air/fuel ratio sensor output,
NOX sensor output, and evaporative system vapor pressure.
---------------------------------------------------------------------------
\47\ Note that, for purposes of the calculated load and torque
parameters for diesel engines, manufacturers would be required to
report the most accurate values that are calculated within the
applicable electronic control unit (e.g., the engine control
computer). ``Most accurate values,'' in this context, would be those
of sufficient accuracy, resolution, and filtering that they could be
used for the purpose of in-use emissions testing with the engine
still in a vehicle (e.g., using portable emissions measurement
equipment).
---------------------------------------------------------------------------
We are also proposing requirements for storage of ``freeze frame''
information at the time a malfunction is detected and a DTC is stored.
The freeze frame provides the operating conditions of the vehicle at
the time of malfunction detection and the DTC associated with the data.
The parameters we are proposing for inclusion in the freeze frame are a
subset of the parameters listed above for the data stream. Note that
storage of only one freeze frame would be required. Manufacturers may
choose to store additional frames, provided that the required frame can
be read using a scan tool meeting SAE J1978 specifications or designed
to communicate with an SAE J1939 network.
We are also proposing that the OBD system store the most recent
monitoring results for most of the major monitors. Manufacturers would
be required to store and make available to the scan tool certain test
information--i.e., the minimum and maximum values that should occur
during proper operation along with the actual test value--of the most
recent monitoring event. ``Passing'' systems would store test results
that are within the test limits, while ``failing'' systems would store
test results that are outside the test limits. The storage of test
results would assist technicians in diagnosing and repairing
malfunctions and would help distinguish between components that are
performing well below the malfunction thresholds from those that are
passing the malfunction thresholds marginally.
viii. Identification Numbers
We are also proposing that manufacturers be required to report two
identification numbers related to the software and specific calibration
values in the onboard computer. The first item, Calibration
Identification Number (CAL ID), would identify the software version
installed in the onboard computer. Software is often changed following
production of the engine. These software changes often make changes to
the emissions control system or the OBD system. We are proposing that
these changes include a new CAL ID and that it be communicated via the
diagnostic connector to the scan tool. The second item, Calibration
Verification Number (CVN), would help to ensure that the current
software has not been corrupted, modified inappropriately, or otherwise
tampered with. Both CAL ID and CVN help ensure the integrity of the OBD
system. The CVN proposal would require manufacturers to develop
sophisticated software algorithms that would essentially be a self-
check calculation of all of the emissions-related software and
calibration values in the onboard computer and would return the result
of the calculation to a scan tool. If the calculated result did not
equal the expected result for that CAL ID, one would know that the
software had been corrupted or otherwise modified. The CVN result would
have to be made available at all times to a generic scan tool.
We are also proposing that the Vehicle Identification Number (VIN)
be communicated via the diagnostic connector to a generic scan tool in
a standardized format. The VIN would be a unique number assigned by the
vehicle manufacturer to every vehicle built. The VIN is commonly used
for purposes of ownership and registration to uniquely identify every
vehicle. By requiring the VIN to be stored in the onboard computer and
available electronically to a generic scan tool, the possibility of a
fraudulent inspection (e.g., by plugging into a different vehicle than
an inspection citation was issued originally to generate a proof of
correction) would be minimized. Electronic access to this number would
also simplify the inspection process and reduce transcription errors
from manual data entry.
We are proposing that the VIN be electronically stored in a control
module on the vehicle, but not that it necessarily be stored in the
engine control module. As long as the VIN is reported correctly and
according to the selected reference document standards, we consider it
irrelevant as to which control module (e.g., engine controller,
instrument cluster controller) contains the information. Further, we
are proposing that the ultimate responsibility would lie with the
engine manufacturer to ensure that every vehicle manufactured with one
of its engines satisfies this requirement. However, we would expect
that the physical task of implementing this requirement would likely be
passed from the engine manufacturer to the vehicle manufacturer via an
additional build specification. Thus, analogous to how the engine
manufacturer currently provides engine purchasers with detailed
specifications regarding engine cooling requirements, additional sensor
inputs, physical mounting specifications, weight limitations, etc., the
engine manufacturer would likely include an additional specification
dictating the need for the VIN to be made available electronically. It
would be left to each engine manufacturer to determine the most
effective method to achieve this, as long as the VIN requirement is
met. Some manufacturers may find it most effective to provide the
capability in the engine control module delivered with the engine
coupled with a mechanism for the vehicle manufacturer to program the
module with the VIN upon installation of the engine into an actual
vehicle. Others may find it more effective to require the vehicle
manufacturer to have the capability built into other modules installed
on the vehicle such as instrument cluster modules, etc. We are aware of
several current vehicles with engines from three different engine
manufacturers that already have the VIN available through engine-
manufacturer specific scan tools; this indicates that such arrangements
already exist in one form or another and that they are working.
5. In-Use Performance Ratio Tracking Requirements
To separately report an in-use performance ratio for each
applicable monitor as discussed in sections II.B through II.D, we are
proposing that manufacturers be required to implement software
algorithms to report a numerator and denominator in the standardized
format specified below and in accordance with the specifications of the
reference documents listed in section II.F.1.
For the numerator, denominator, general denominator, and ignition
cycle counter:
Each number must have a minimum value of zero and a
maximum value of 65,535 with a resolution of one.
Each number must be reset to zero only when a non-volatile
random access memory (NVRAM) reset occurs (e.g., reprogramming event)
or, if the numbers are stored in keep-alive memory (KAM), when KAM is
lost due to an interruption in electrical power to the control module
(e.g., battery disconnect). Numbers may not be reset to zero under any
other circumstances including when commanded to do so via a scan tool
command to clear DTCs or reset KAM.
If either the numerator or denominator for a specific
component reaches the maximum value of 65,535 2, both
numbers should be divided by two before either is incremented again to
avoid overflow problems.
[[Page 3250]]
If the ignition cycle counter reaches the maximum value of
65,535 2, the ignition cycle counter should rollover and
increment to zero on the next ignition cycle to avoid overflow
problems.
If the general denominator reaches the maximum value of
65,535 2, the general denominator should rollover and
increment to zero on the next drive cycle that meets the general
denominator definition to avoid overflow problems.
If an engine is not equipped with a component (e.g.,
oxygen sensor bank 2, secondary air system), the corresponding
numerator and denominator for that specific component should always be
reported as zero.
For the in-use performance ratio:
The ratio should have a minimum value of zero and a
maximum value of 7.99527 with a resolution of 0.000122.
A ratio for a specific component should be considered to
be zero whenever the corresponding numerator is equal to zero and the
corresponding denominator is not zero.
A ratio for a specific component should be considered to
be the maximum value of 7.99527 if the corresponding denominator is
zero or if the actual value of the numerator divided by the denominator
exceeds the maximum value of 7.99527.
For engine run time tracking on all gasoline and diesel engines,
manufacturers would be required to implement software algorithms to
individually track and report in a standardized format the engine run
time while being operated in the following conditions:
Total engine run time
Total idle run time (with ``idle'' defined as accelerator
pedal released by driver, vehicle speed less than or equal to one mile
per hour, and PTO not active);
Total run time with PTO active.
Each of the above engine run time counters would have the following
numerical value specifications:
Each numerical counter must be a four-byte value with a
minimum value of zero at a resolution of one minute per bit.
Each numerical counter must be reset to zero only when a
nonvolatile memory reset occurs (e.g., a reprogramming event).
Numerical counters cannot be reset to zero under any other
circumstances including a scan tool (generic or enhanced) command to
clear DTCs or reset KAM.
When any of the individual numerical counters reaches its
maximum value, all counters must be divided by two before any are
incremented again. This is meant to avoid overflow problems.
6. Exceptions to Standardization Requirements
For alternative-fueled engines derived from a diesel-cycle engine,
we are proposing that the manufacturer be allowed to meet the
standardized requirements discussed in this section that are applicable
to diesel engines rather than meeting the requirements applicable to
gasoline engines.
G. Implementation Schedule, In-Use Liability, and In-Use Enforcement
1. Implementation Schedule and In-Use Liability Provisions
Table II.G-1 summarizes the proposed implementation schedule for
the OBD monitoring requirements--i.e., the proposed certification
requirements and in-use liabilities. More detail regarding the
implementation schedule and liabilities can be found in the sections
that follow.
Table II.G-1.--OBD Certification Requirements and In-use Liability for
Diesel Fueled and Gasoline Fueled Engines over 14,000 Pounds: Monitoring
Requirements
------------------------------------------------------------------------
Certification
Model year Applicability requirement In-use liability
------------------------------------------------------------------------
2010-2012......... Parent rating Full liability Full liability
within 1 to thresholds to 2x
compliant according to thresholds. \c\
engine family. certification
\a\ demonstration
procedures. \b\
Child ratings Certification Liability to
within the documentation monitor and
compliant only (i.e., no detect as noted
engine family. certification in
demonstration); certification
no liability to documentation.
thresholds.
All other engine None............ None.
families and
ratings.
2013-2015......... Parent rating Full liability Full liability
from 2010-2012 to thresholds to 2x
and parent according to thresholds.
rating within 1- certification
2 additional demonstration
engine families. procedures.
Child ratings Full liability Full liability
from 2010-2012 to thresholds to 2x
and parent but thresholds.
ratings from certification
any remaining documentation
engine families only.
or OBD
groups.\d\
Additional Certification Liability to
engine ratings. documentation monitor and
only; no detect as noted
liability to in
thresholds. certification
demonstration.
2016-2018........ One rating from Full liability Full liability
1-3 engine to thresholds to thresholds.
families and/or according to
OBD groups. certification
demonstration
procedures.
Remaining Full liability Full liability
ratings. to thresholds to 2x
but thresholds.
certification
documentation
only.
2019+............. One rating from Full liability Full liability
1-3 engine to thresholds to thresholds.
families and/or according to
OBD groups. certification
demonstration
procedures.
Remaining Full liability Full liability
ratings. to thresholds to thresholds.
but
certification
documentation
only.
------------------------------------------------------------------------
Notes: (a) Parent and child ratings are defined in section II.G; which
rating(s) serves as the parent rating and which engine families must
comply is not left to the manufacturer, as discussed in section II.G.
(b) The certification demonstration procedures and the certification
documentation requirements are discussed in section VIII.B. (c) Where
in-use liability to thresholds and 2x thresholds is noted,
manufacturer liability to monitor and detect as noted in their
certification documentation is implied. (d) OBD groups are groupings
of engine families that use similar OBD strategies and/or similar
emissions control systems, as described in the text.
For the 2010 through 2012 model years, manufacturers would be
required to implement OBD on one engine family. All other 2010 through
2012 engine families would not be subject to any OBD requirements
unless otherwise required to do so (e.g., to demonstrate that SCR
equipped vehicles will not be operated without urea). For 2013,
[[Page 3251]]
manufacturers would be required to implement OBD on all engine
families.
We are proposing this implementation schedule for several reasons.
First, industry has made credible arguments that their resources are
stretched to the limit developing and testing strategies for compliance
with the 2007/2010 heavy-duty highway emissions standards. We do not
want to jeopardize their success toward that goal by being too
aggressive with our OBD program. Second, OBD is a complex and difficult
regulation with which to comply. We believe that our implementation
schedule would give industry the opportunity to introduce OBD systems
on a limited number of engines giving them and us very valuable
learning experience. Should mistakes or errors in regulatory
interpretation occur, the ramifications would be limited to only a
subset of the new vehicle fleet rather than the entire new vehicle
fleet. Lastly, the proposed OBD requirements outlined above, and the
production vehicle evaluation provisions discussed in Section VIII,
reflect 10 to 20 years of learning by EPA, CARB, and industry
(primarily the light-duty gasoline industry) as to what works and what
does not work. This is, perhaps, especially true for those OBD elements
that involve the interface between the OBD system and service and I/M
inspection personnel. Gasoline manufacturers have had the ability to
evolve their OBD systems along with this learning process. However,
diesel engine manufacturers have not really been involved in this
learning process and, as a result, 100 percent implementation in 2010
would be analogous to implementing 10 to 20 years of OBD learning in
one implementation step. We believe that implementing in two or three
gradual steps rather than one big step will benefit everyone involved.
Table II.G-1 makes reference to ``parent'' and ``child'' ratings.
In general, engine manufacturers certify an engine family that consists
of several ratings having slightly different horsepower and/or torque
characteristics but no differences large enough to require a different
engine family designation. For emissions certification, the parent
rating--i.e., the rating for which emissions data are submitted to EPA
for the purpose of demonstrating emissions compliance--is defined as
the ``worst case'' rating. This worst case rating is the rating
considered as having the worst emissions performance and, therefore,
its compliance demonstrates that all other ratings within the family
must comply. For OBD purposes, we wanted to limit the burden on
industry--hence the proposal for only one compliant engine family in
2010--yet maximize the impact of the OBD system. Therefore, for model
years 2010 through 2012, we are defining the OBD parent rating as the
rating having the highest weighted projected sales within the engine
family having the highest weighted projected sales, with sales being
weighted by the useful life of the engine rating. Table II.G-2 presents
a hypothetical example for how this would work. Using this approach,
the OBD compliant engine family in 2010 would be the engine family
projected to produce the most in-use emissions (based on sales weighted
by expected miles driven). Likewise, the fully liable parent OBD rating
would be the rating within that family projected to produce the most
in-use emissions.
Table II.G-2.--Hypothetical Example of How the OBD Parent and Child Ratings Would Be Determined
--------------------------------------------------------------------------------------------------------------------------------------------------------
OBD weighting-- OBD weighting--
Projected Certified engine rating \a\ engine family \b\
OBD group Engine family Rating sales useful life (billions) (billions)
--------------------------------------------------------------------------------------------------------------------------------------------------------
I............................................ A 1 10,000 285,000 2.85 14.25
........................ 2 40,000 285,000 11.4 .................
B 1 10,000 435,000 4.35 21.60
........................ 2 20,000 435,000 8.70 .................
........................ 3 30,000 285,000 8.55 .................
II........................................... C 1 20,000 110,000 2.20 7.70
........................ 2 50,000 110,000 5.50 .................
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: (a) For engine family A, rating 1, 10,000 x 285,000 / 1 billion = 2.85.
(b) For engine family A, 2.85 + 11.4 = 14.25.
In the example shown in Table II.G-2, the compliant engine family
in 2010 would be engine family B and the parent OBD rating within that
family would be rating 2. The other OBD compliant ratings within engine
family B would be dubbed the ``child'' ratings. For model years 2013
through 2015, the parent ratings would be those ratings having the
highest weighted projected sales within each of the one to three engine
families having the highest weighted projected sales, with sales being
weighted by the useful life of the engine rating. In the example shown
in Table II.G-2, the parent ratings would be rating 2 of engine family
A, rating 2 of engine family B, and rating 2 of engine family C (Note
that this is only for illustration purposes since our proposal would
not require that a manufacturer with only three engine families have
three parent ratings and instead would require only one).
The manufacturer would not need to submit test data demonstrating
compliance with the emissions thresholds for the child ratings. We
would fully expect these child ratings to use OBD calibrations--i.e.,
malfunction trigger points--that are identical or nearly so to those
used on the parent rating. However, we would allow manufacturers to
revise the calibrations on their child ratings where necessary so as to
avoid unnecessary or inappropriate MIL illumination. Such revisions to
OBD calibrations have been termed ``extrapolated'' OBD calibrations
and/or systems. The revisions to the calibrations on child ratings and
the rationale for them would need to be very clearly described in the
certification documentation.
For the 2013 and later model years, we are proposing that
manufacturers certify one to three parent ratings. The actual number of
parent ratings would depend upon the manufacturer's fleet and would be
based on both the emissions control system architectures present in
their fleet and the similarities/differences of the engine families in
their fleet. For example, a manufacturer that uses a DPF with
NOX adsorber on each of the engines would have only one
system architecture. Another manufacturer that uses a DPF with
NOX adsorber on some engines and a DPF with SCR on others
would have at least two architectures. We would expect that
manufacturers would group similar architectures and similar engine
[[Page 3252]]
families into so called ``OBD groups.'' These OBD groups would consist
of a combination of engines, engine families, or engine ratings that
use the same OBD strategies and similar calibrations. The manufacturer
would be required to submit details regarding their OBD groups as part
of their certification documentation that shows the engine families and
engine ratings within each OBD group for the coming model year. While a
manufacturer may end up with more than three OBD groups, we do not
intend to require a parent rating for more than three OBD groups.
Therefore, in the example shown in Table II.G-2, rather than submitting
test data for the three parent ratings as suggested above, the OBD
grouping would result in the parent ratings being rating 2 of engine
family B and rating 2 of engine family C. These parents would represent
OBD groups I and II, and the manufacturer's product line. For 2013
through 2015, we intend to allow the 2010 parent to again act as a
parent rating and, provided no significant changes had been made to the
engine or its emissions control system, complete carryover would be
possible. However, for model years 2016 and beyond, we would work
closely with CARB staff and the manufacturer to determine the parent
ratings so that the same ratings are not acting as the parents every
year. In other words, our definitions for the OBD parent ratings as
discussed here apply only during the years 2010 through 2012 and again
for the years 2013 through 2015. We request comment on this approach.
In addition to this gradual certification implementation schedule,
we are proposing some relaxations for in-use liability during the 2010
through 2018 model years. The first such relaxation is higher interim
in-use compliance standards for those OBD monitors calibrated to
specific emissions thresholds. For the 2010 through 2015 model years,
an OBD monitor on an in-use engine would not be considered non-
compliant (i.e., subject to enforcement action) unless emissions
exceeded twice the OBD threshold without detection of a malfunction.
For example, for an EGR monitor on an engine with a NOX FEL
of 0.2 g/bhp-hr and an OBD threshold of 0.5 g/bhp-hr (i.e., the
NOX FEL+0.3), a manufacturer would not be subject to
enforcement action unless emissions exceeded 1.0 g/bhp-hr
NOX without a malfunction being detected. For the model
years 2016 through 2018, parent ratings would be liable to the
certification emissions thresholds, but child ratings and other ratings
would remain liable to twice the certification thresholds. Beginning in
the 2019 model year, all families and all ratings would be liable to
the certification thresholds.
The second in-use relaxation is a limitation in the number of
engines that would be liable for in-use compliance with the OBD
emissions thresholds. For 2010 through 2012, we are proposing that
manufacturers be fully liable in-use to twice the thresholds for only
the OBD parent rating. The child ratings within the compliant engine
family would have liability for monitoring in the manner described in
the certification documentation, but would not have liability for
detecting a malfunction at the specified emissions thresholds. For
example, a child rating's DPF monitor designed to operate under
conditions X, Y, and Z and calibrated to detect a backpressure within
the range A to B would be expected to do exactly that during in-use
operation. However, if the tailpipe emissions of the child engine were
to exceed the applicable OBD in-use thresholds (i.e., 2x the
certification thresholds during 2010-2015), despite having a
backpressure within range A to B under conditions X, Y, and Z, there
would be no in-use OBD failure nor cause for enforcement action. In
fact, we would expect the OBD monitor to determine that the DPF was
functioning properly since its backpressure was in the acceptable
range. For model years 2013 through 2015, this same in-use relaxation
would apply to those engine families that do not lie within an engine
family for which a parent rating has been certified. For 2016 and later
model years, all engines would have some in-use liability to
thresholds, either the certification thresholds or twice those
thresholds.
These in-use relaxations are meant to provide ample time for
manufacturers to gain experience without an excessive level of risk for
mistakes. They would also allow manufacturers to fine-tune their
calibration techniques over a six to ten year period.
We are also proposing some a specific implementation schedule for
the standardization requirements discussed in section II.F. We
initially intended to require that any compliant OBD engine family
would be required to implement all of the standardization requirements.
However, we became concerned that, during model years 2010 through
2012, we could have a situation where OBD compliant engines from
manufacturer A might be competing against non-OBD engines from
manufacturer B for sales in the same truck. In such a case, the truck
builder would be placed in a difficult position of needing to design
their truck to accommodate OBD compliant engines--along with a
standardized MIL, a specific diagnostic connector location
specification, etc.--and non-OBD engines. After consideration of this
almost certain outcome, we have decided to limit the standardization
requirements that must be met during the 2010 through 2012 model years.
Beginning in 2013, all engines will be OBD compliant and this would
become a moot issue. Table II.G-3 shows the proposed implementation
schedule for standardization requirements.
Table II.G-3.--OBD Standardization Requirements for Diesel Fueled and
Gasoline Fueled Engines Over 14,000 Pounds
------------------------------------------------------------------------
Required Waived
Model year Applicability standardization standardization
features features
------------------------------------------------------------------------
2010-2012......... Parent and Child Emissions Standardized
ratings within related connector
1 compliant (II.F.4) except (II.F.2).
engine family. for the Dedicated
\a\ requirement to (i.e.,
make the data regulated OBD-
available in a only) MIL.
standardized Communication
format or in protocols
accordance with (II.F.3).
SAE J1979/1939 Emissions
specifications) related
. MIL functions
activation and (II.F.4) with
deactivation.\b respect to the
\ Performance requirement to
tracking--calcu make the data
lation of available in a
numerators, standardized
denominators, format or in
ratios. accordance with
SAE J1979/1939
specifications)
Other engine None............ All.
families.
2013+............. All engine All............. None.
families and
ratings.
------------------------------------------------------------------------
Notes: (a) Parent and child ratings are defined in section II.G; which
rating serves as the parent rating and which engine families must
comply is not left to the manufacturer, as discussed in section II.G.
(b) There would be no requirement for a dedicated MIL and no
requirement to use a specific MIL symbol, only that a MIL be used and
that it use the proposed activation/deactivation logic.
[[Page 3253]]
2. In-Use Enforcement
When conducting our in-use enforcement investigations into OBD
systems, we intend to use all tools we have available to analyze the
effectiveness and compliance of the system. These tools may include on-
vehicle emission testing systems such as the portable emissions
measurement systems (PEMS). We would also use scan tools and data
loggers to analyze the data stream information to compare real world
operation to the documentation provided at certification.
Importantly, we would not intend to pursue enforcement action
against a manufacturer for not detecting a failure mode that could not
have been reasonably predicted or otherwise detected using monitoring
methods known at the time of certification. For example, we are
proposing a challenging set of requirements for monitoring of DPF
systems. As of today, engine manufacturers are reasonably confident in
their ability to detect certain DPF failure modes at or near the
proposed thresholds--e.g., a leaking DPF resulting from a cracked
substrate--but are not confident in their ability to detect some other
DPF failure modes--e.g., a leaking DPF resulting from a partially
melted substrate. If a partially melted substrate indeed cannot be
detected and this is known during the certification process, we cannot
expect such a failure to be detected on an in-use vehicle.
We also want to make it clear who would be the responsible party
should we pursue any in-use enforcement action with respect to OBD. We
are very familiar with the heavy-duty industry and its tendency toward
separate engine and component suppliers. This contrasts with the light-
duty industry which tends toward a more vertically integrated
structure. The non-vertically integrated nature of the heavy-duty
industry can present unique difficulties for OBD implementation and for
OBD enforcement. With the complexity of OBD systems, especially those
meeting the requirements being proposed today, we would expect the
interactions between the various parties involved--engine manufacturer,
transmission manufacturer, vehicle manufacturer, etc.--to be further
complicated. Nonetheless, in the end the vast majority of the proposed
OBD requirements would apply directly to the engine and its associated
emission controls, and the engine manufacturer would have complete
responsibility to ensure that the OBD system performs properly in-use.
Given the central role the engine and engine control unit would play in
the OBD system, we are proposing that the party certifying the engine
and OBD system (typically, the engine manufacturer) be the responsible
party for in-use compliance and enforcement actions. In this role, the
certifying party would be our sole point of contact for potential
noncompliances identified during in-use or enforcement testing. We
would leave it to the engine manufacturer to determine the ultimate
party responsible for the potential noncompliance (e.g., the engine
manufacturer, the vehicle manufacturer, or some other supplier). In
cases where remedial action such as an engine recall would be required,
the certifying party would take on the responsibility of arranging to
bring the engines or OBD systems back into compliance. Given that
heavy-duty engines are already subject to various emission requirements
including engine emission standards, labels, and certification, engine
manufacturers currently impose restrictions via signed agreements with
engine purchasers to ensure that their engines do not deviate from
their certified configuration when installed. We would expect the OBD
system's installation to be part of such agreements in the future.
H. Proposed Changes to the Existing 8,500 to 14,000 Pound Diesel OBD
Requirements
We are also proposing changes to our OBD requirements for diesel
engines used in heavy-duty vehicles under 14,000 pounds (see 40 CFR
86.005-17 for engine-based requirements and 40 CFR 86.1806-05 for
vehicle or chassis-based requirements). Table II.H-1 summarizes the
proposed changes to under 14,000 pound heavy-duty diesel emissions
thresholds at which point a component or system has failed to the point
of requiring an illuminated MIL and a stored DTC. Table II.H-2
summarizes the proposed changes for diesel engines used in heavy-duty
applications under 14,000 pounds. The proposed changes are meant to
maintain consistency with the diesel OBD requirements we are proposing
for over 14,000 pound applications.
Table II.H-1.--Proposed New, or Proposed Changes to Existing, Emissions Thresholds for Diesel Fueled CI Heavy-
duty Vehicles Under 14,000 Pounds (g/mi)
----------------------------------------------------------------------------------------------------------------
Component/monitor MY NMHC CO NOX PM
----------------------------------------------------------------------------------------------------------------
NMHC catalyst system......... 2010-2012..... 2.5x.
2013+......... 2x.
NOX catalyst system.......... 2007-2009..... .............. .............. 3x............
2010+......... .............. .............. +0.3.
DPF system................... 2010-2012..... 2.5x.......... .............. .............. 4x.
2013+......... 2x............ .............. .............. +0.04.
Air-fuel ratio sensors 2007-2009..... 2.5x.......... 2.5x.......... 3x............ 4x.
upstream.
2010-2012..... 2.5x.......... 2.5x.......... +0.3.......... +0.02.
2013+......... 2x............ 2x............ +0.3.......... +0.02.
Air-fuel ratio sensors 2007-2009..... 2.5x.......... .............. 3x............ 4x.
downstream.
2010-2012..... 2.5x.......... .............. +0.3.......... 4x.
2013+......... 2x............ .............. +0.3.......... +0.04.
NOX sensors.................. 2007-2009..... .............. .............. 4x............ 5x.
2010-2012..... .............. .............. +0.3.......... 4x.
2013+......... .............. .............. +0.3.......... +0.04.
``Other monitors'' with 2007-2009..... 2.5x.......... 2.5x.......... 3x............ 4x.
emissions thresholds.
2010-2012..... 2.5x.......... 2.5x.......... +0.3.......... 4x.
2013+......... 2x............ 2x............ +0.3.......... +0.02.
----------------------------------------------------------------------------------------------------------------
Notes: MY=Model Year; 2.5x means a multiple of 2.5 times the applicable emissions standard; +0.3 means the
standard plus 0.3; not all proposed monitors have emissions thresholds but instead rely on functionality and
rationality checks as described in section II.D.4.
[[Page 3254]]
Table II.H-2.--Proposed New, or Proposed Changes to Existing, Emissions Thresholds for Diesel Fueled CI Engines Used in Heavy-duty Vehicles Under 14,000
Pounds (g/bhp-hr)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Component/Monitor MY Std/FEL NMHC CO NOX PM
--------------------------------------------------------------------------------------------------------------------------------------------------------
NMHC catalyst system............. 2010-2012......... All............... 2.5x.
2013+............. All............... 2x.
NOX catalyst system.............. 2007-2009......... >0.5 NOX.......... ................. ................. 1.75x.
2007-2009......... <=0.5 NOX......... ................. ................. +0.5.
2010+............. All............... ................. ................. +0.3.
DPF system....................... 2010-2012......... All............... 2.5x............. ................. ................. 0.05/+0.04.
2013+............. All............... 2x............... ................. ................. 0.05/+0.04.
Air-fuel ratio sensors upstream.. 2007-2009......... >0.5 NOX.......... 2.5x............. 2.5x............. 1.75x............ 0.05/+0.04.
2007-2009......... <=0.5 NOX......... 2.5x............. 2.5x............. +0.5............. 0.05/+0.04.
2010-2012......... All............... 2.5x............. 2.5x............. +0.3............. 0.03/+0.02.
2013+............. All............... 2x............... 2x............... +0.3............. 0.03/+0.02.
Air-fuel ratio sensors downstream 2007-2009......... >0.5 NOX.......... 2.5x............. ................. 1.75x............ 0.05/+0.04.
2007-2009......... <=0.5 NOX......... 2.5x............. ................. +0.5............. 0.05/+0.04.
2010-2012......... All............... 2.5x............. ................. +0.3............. 0.05/+0.04.
2013+............. All............... 2x............... ................. +0.3............. 0.05/+0.04.
NOX sensors...................... 2007-2009......... >0.5 NOX.......... ................. ................. 1.75x............ 0.05/+0.04.
2007-2009......... <=0.5 NOX......... ................. ................. +0.5............. 0.05/+0.04.
2010+............. All............... ................. ................. +0.3............. 0.05/+0.04.
``Other monitors'' with emissions 2007-2009......... >0.5 NOX.......... 2.5x............. 2.5x............. 1.75x............ 0.05/+0.04.
thresholds.
2007-2009......... <=0.5 NOX......... 2.5x............. 2.5x............. +0.5............. 0.05/+0.04.
2010-2012......... All............... 2.5x............. 2.5x............. +0.3............. 0.03/+0.02.
2013+............. All............... 2x............... 2x............... +0.3............. 0.03/+0.02.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: MY=Model Year; 2.5x means a multiple of 2.5 times the applicable emissions standard or family emissions limit (FEL); +0.3 means the standard or
FEL plus 0.3; 0.05/+0.04 means an absolute level of 0.05 or an additive level of the standard or FEL plus 0.04, whichever level is higher; not all
proposed monitors have emissions thresholds but instead rely on functionality and rationality checks as described in section II.D.4.
1. Selective Catalytic Reduction and Lean NOX Catalyst
Monitoring
We are proposing that the 8,500 to 14,000 pound SCR and lean
NOX catalyst monitoring requirements mirror those discussed
in section II.B.6. The current regulations require detection of a
NOX catalyst malfunction before emissions exceed 1.5x the
emissions standards. We no longer believe that such a tight threshold
level is appropriate for diesel SCR and lean NOX catalyst
systems. We believe that such a tight threshold could result in too
many false failure indications. The required monitoring conditions with
respect to performance tracking (discussed in section II.B.6.c) would
not apply for under 14,000 pound heavy-duty applications since we do
not have performance tracking requirements for under 14,000 pound
applications. We are proposing this change for the 2007 model year.
2. NOX Adsorber System Monitoring
We are proposing that the 8,500 to 14,000 pound NOX
adsorber monitoring requirements mirror those discussed in section
II.B.7. The current regulations require detection of a NOX
adsorber malfunction before emissions exceed 1.5x the emissions
standards. We no longer believe that such a tight threshold level is
appropriate for diesel NOX adsorber systems. We believe that
such a tight threshold could result in too many false failure
indications. The required monitoring conditions with respect to
performance tracking (discussed in section II.B.7.c) would not apply
for under 14,000 pound heavy-duty applications since we do not have
performance tracking requirements for under 14,000 pound applications.
We are proposing this change for the 2007 model year.
3. Diesel Particulate Filter System Monitoring
We are proposing that the 8,500 to 14,000 pound DPF monitoring
requirements mirror those discussed in section II.B.8. Our current
regulations require detection of a catastrophic failure only. The
proposed monitoring requirements discussed in section II.B.8 would be
far more comprehensive and protective of the environment than would a
catastrophic failure monitor. The required monitoring conditions with
respect to performance tracking (discussed in section II.B.8.c) would
not apply for under 14,000 pound heavy-duty applications since we do
not have performance tracking requirements for under 14,000 pound
applications. We are proposing no changes to the DPF monitoring
requirements in the 2007 to 2009 model years because there is not
sufficient lead time for manufacturers to develop a new monitor. The
new, more stringent monitoring requirements would begin in the 2010
model year, with a further tightening of the DPF NMHC threshold in the
2013 model year as is also proposed for over 14,000 pound applications.
4. NMHC Converting Catalyst Monitoring
We are proposing that the 8,500 to 14,000 pound NMHC converting
catalyst monitoring requirements mirror those discussed in section
II.B.5. Our current regulations do not require the monitoring of NMHC
catalysts on diesel applications. The proposed monitoring requirements
discussed in section II.B.5 would be far more comprehensive and
protective of the environment than the current lack of any requirement.
The required monitoring conditions with respect to performance tracking
(discussed in section II.B.8.c) would not apply for under 14,000 pound
heavy-duty applications since we do not have performance tracking
requirements for under 14,000 pound applications. We are not proposing
this new threshold for the 2007 to 2009 model years because there is
not sufficient lead time for manufacturers to develop a new monitor.
The new, more stringent monitoring requirements would begin in the 2010
model year, with a further tightening of the NMHC threshold in the 2013
model year as is also proposed for over 14,000 pound applications.
5. Other Monitors
We are also proposing changes to the emissions thresholds for all
other diesel monitors in the 8,500 to 14,000 pound range (e.g.,
NOX sensors, air fuel ratio
[[Page 3255]]
sensors, etc.). These proposed changes are meant to maintain
consistency with the proposed changes for over 14,000 pound
applications. We believe that these proposed thresholds are far more
appropriate for diesel applications than the thresholds we have in our
current OBD requirements which are, generally, 1.5 times the applicable
standards. None of the proposed thresholds represents a new threshold
where none currently exists. Instead, they represent different
thresholds that would require, in most cases, malfunction detection at
different emissions levels than would be required by our current OBD
requirements.
6. CARB OBDII Compliance Option and Deficiencies
We are also proposing some changes to our deficiency provisions for
vehicles and engines meant for vehicles under 14,000 pounds. We have
included specific mention of air-fuel ratio sensors and NOX
sensors where we had long referred only to oxygen sensors. We have also
updated the referenced CARB OBDII document that can be used to satisfy
the federal OBD requirements.\48\
---------------------------------------------------------------------------
\48\ See 13 CCR 1968.2, released August 11, 2006, Docket
ID EPA-HQ-OAR-2005-0047-0005.
---------------------------------------------------------------------------
I. How Do the Proposed Requirements Compare to California's?
The California Air Resources Board (CARB) has its own OBD
regulations for engines used in vehicles over 14,000 pounds GVWR.\49\
(13 CCR 1971.1) In August of 2004, EPA and CARB signed a memorandum of
agreement to work together to develop a single, nationwide OBD program
for engines used in vehicles over 14,000 pounds.\50\ We believe that,
for the most part, we have been successful in doing so at least for the
early years of implementation. Nonetheless, there are differences in
some of the details contained within each regulation. These differences
are summarized here and we request comment on all of these differences.
---------------------------------------------------------------------------
\49\ 13 CCR 1971.1, Docket ID EPA-HQ-OAR-2005-0047-
0006.
\50\ ``Memorandum of Agreement: On-road Heavy-duty Diagnostic
Regulation Development,'' signed by Chet France, U.S. EPA, and Tom
Cackette, California ARB, August 11, 2004, Docket ID EPA-
HQ-OAR-2005-0047-0002.
---------------------------------------------------------------------------
The first difference is that the CARB regulation contains some more
stringent thresholds beginning in the 2013 timeframe for some engines
and 2016 for all engines. Specifically, CARB's PM threshold for diesel
particulate filters (DPF) and exhaust gas sensors downstream of
aftertreatment devices, and their NOX threshold for
NOX aftertreatment devices and exhaust gas sensors
downstream of aftertreatment devices, become more stringent in 2013 for
some engines and 2016 for all. We are not proposing these more
stringent thresholds--our proposed thresholds are shown in Table II.B-
1. At this time, EPA is not in a position to propose these more
stringent OBD thresholds for the national program. The industry
believes that CARB's more stringent NOX and PM thresholds
for 2013 and 2016 are not technically feasible. EPA is reviewing these
longer term OBD thresholds, but at this time we have not made a
decision regarding the feasibility and the appropriateness of these
longer term thresholds. Because these thresholds do not take effect
until model year 2013 at the earliest, we do not believe it is
necessary to make such a determination in this rulemaking. It would be
our intention to monitor the progress made towards complying with the
2010 thresholds contained in today's proposal and potentially revisit
the appropriateness of more stringent OBD thresholds for model year
2013 and later in the future. CARB has made commitments to review their
HD OBD program every two years and they can consider making changes to
their long-term program during this biennial review process. EPA's
regulatory development process does not lend itself to making updates
every two years because the Federal rulemaking process tends to be
lengthier than CARB's. As mentioned above, we intend to monitor the
CARB long-term thresholds during the coming years, and if we determine
that more stringent thresholds are appropriate, we would consider
changing our thresholds to include the more stringent thresholds
through a notice and comment rulemaking process.
CARB also has some slightly different certification demonstration
requirements in the 2011 and 2012 model years. They are requiring
demonstration testing of the child ratings from the 2010 model year
certified engine family for 2011 and 2012 model year certification. As
Table II.B-1 shows, we are not requiring such demonstration testing in
the 2011 and 2012 model years provided the child ratings meet the
requirements of certification carry-over. Further, CARB is requiring
that one engine rating from one to three engine families undergo full
certification demonstration testing in the 2013 model year and every
model year thereafter. In contrast, EPA is requiring that one to three
engine ratings be fully demonstrated in the 2013 model year and then
carry-over through the 2015 model year (again, provided the engine
ratings meet the requirements of certification carry-over). In 2016 and
subsequent model years, EPA would require that one to three engine
ratings be fully demonstrated on an ``as needed'' basis. In the same
vein, our evaluation protocol associated with certification
demonstration testing, as discussed in section VIII.C, requires less
testing than is required in CARB's regulation.
Our OBD requirements for over 14,000 pounds do not contain any
provisions to monitor control strategies associated with idle emission
control strategies because EPA does not have currently any regulatory
requirements that specifically target idle emissions control
strategies.\51\ We are not proposing a provision to charge fees
associated with OBD deficiencies as CARB does. We are also not
proposing provisions for ``retroactive deficiencies'' as CARB has. Our
deficiency provisions along with our misbuild and other in-use
enforcement programs accomplish the same thing. Deficiencies are
discussed in section VIII.D.\52\
---------------------------------------------------------------------------
\51\ Note that, by idle emission control strategies we mean
strategies that, for example, shut down the engine after 10 minutes
of constant idle. We do not mean strategies that control emissions
during engine idles that occur at stop lights or in congested
traffic.
\52\ See also proposed Sec. 86.010-18(n).
---------------------------------------------------------------------------
For diesel engines used in heavy-duty vehicles under 14,000 pounds,
our proposed OBD requirements are in line with those recently proposed
by CARB.\53\ Our proposed requirements are also in line--both the
technical aspects and the implementation timing aspects--with our
proposed requirements for over 14,000 pound diesel applications. We are
also proposing diesel vehicle-based OBD requirements in line with the
proposed diesel engine-based requirements. In contrast, CARB does not
have diesel thresholds in terms of ``grams per mile'' specified in
their regulation for the 8,500 to 14,000 pound range.
---------------------------------------------------------------------------
\53\ See 13 CCR 1968.2, released August 11, 2006, Docket
ID EPA-HQ-OAR-2005-0047-0005.
---------------------------------------------------------------------------
Specifically for gasoline engines meant for applications over
14,000 pounds, our proposal differs from CARB's in that we are not
requiring detection of catalysts that are less than 50 percent
effective at converting emissions.\54\ We are not requiring this
because we are relying on the emissions threshold of 1.75 times the
applicable standard as a means of defining a catalyst system
malfunction. We are also proposing some differences with respect to
misfire monitoring. Most notably, we are not proposing a provision
analogous
[[Page 3256]]
to CARB's provision that allows the Executive Officer to approve
misfire monitor disablement or alternative malfunction criteria on a
case by case basis.\55\ In general, we prefer to avoid having
regulatory provisions that are implemented on a case by case basis. For
similar reasons, we are also not proposing a provision analogous to
CARB's provision that allows the Executive Officer to revise the
orifice for evaporative leak detection if the most reliable monitoring
strategy cannot detect the required orifice.\56\
---------------------------------------------------------------------------
\54\ See 13 CCR 1971.1(f)(6.2.1)(B) and compare to proposed
Sec. 86.010-18(h)(6)(ii).
\55\ See 13 CCR 1971.1(f)(2.3.4)(D) and compare to proposed
Sec. 86.010-18(h)(2)(iii)(D).
\56\ See 13 CCR 1971.1(f)(7.2.3) and compare to proposed Sec.
86.010-18(h)(7)(ii)(B) and (C).
---------------------------------------------------------------------------
III. Are the Proposed Monitoring Requirements Feasible?
Some of the OBD monitoring strategies discussed here would be
intrusive monitors that would result in very brief emissions increases,
or spikes, for the sake of determining if certain emissions control
components/systems are working properly during the remaining 99 percent
or more of the engine's operation. While these emissions spikes are
brief, and their levels cannot be meaningfully predicted or estimated,
we are concerned about strategies that might give little concern to
emissions during such spikes in favor of an easier monitor. We request
comment on this issue--should such strategies be allowed or should such
strategies be prohibited? If a commenter has the latter opinion, then
suggestions should be provided for how the monitoring requirements
should be changed to allow for a non-intrusive monitor--i.e., one that
could run during normal operation or operation ``on the cycle''--that
may not provide the monitoring capability nor the control expected by
the requirements we are proposing.
A. Feasibility of the Monitoring Requirements for Diesel/Compression-
Ignition Engines
1. Fuel System Monitoring
a. Fuel Pressure Monitoring
Manufacturers control fuel pressure by using a closed-loop feedback
algorithm that allows them to increase or decrease fuel pressure until
the fuel pressure sensor indicates they have achieved the desired fuel
pressure. For the common-rail OBD systems certified in the under 14,000
pound category, the manufacturers are monitoring the actual fuel system
pressure sensed by a fuel rail pressure sensor, comparing it to the
target fuel system pressure stored in a software table or calculated by
an algorithm inside the onboard computer, and indicating a malfunction
if the magnitude of the difference between these two exceeds an
acceptable level. The error limits are established by engine
dynamometer emission tests to ensure that a malfunction would be
detected before emissions exceed the applicable thresholds.
In cases where no fuel pressure error can generate a large enough
emission increase to exceed the applicable thresholds, manufacturers
are required to set the malfunction trigger at their fuel pressure
control limits (e.g., when they reach a point where they can no longer
increase or decrease fuel pressure to achieve the desired fuel
pressure). This monitoring requirement has been demonstrated as
technically feasible given that several under 14,000 pound diesels
already meet this requirement. Further, the nature of a closed-loop
algorithm is that such a system is inherently capable of being
monitored because it simply requires analysis of the same closed-loop
feedback parameter being used by the system for control purposes.
Another promising technology is a pressure sensing glow plug. The
glow plug is an electronic device in the cylinder of most diesel
engines used to facilitate combustion during cold engine starting
conditions. Glow plugs are being developed that incorporate a pressure
sensor capable of detecting the quality of combustion within the
cylinder.\57\ Pressure-sensing glow plugs provide feedback to the
engine-management system that controls the timing and quantity of fuel
injected into the cylinder. This feedback allows the engine electronics
to adjust the injection characteristics so the engine avoids fuel-
mixture combinations that generate high levels of NOX. In
this sense, a feedback loop is available that works like the oxygen
sensor in a gasoline engine exhaust system. By measuring the quality of
combustion, a determination can also be made about the quality of the
fuel injection event--the pressure of fuel delivered, quantity of fuel
delivered, timing of fuel delivered.
---------------------------------------------------------------------------
\57\ ``Spotlight on Technology: Smart glowplugs may make Clean
Diesels cost-effective Pressure-sensing units could let designers
cut NOX aftertreatment,'' Tony Lewin, Automotive News,
February 6, 2006.
---------------------------------------------------------------------------
b. Fuel Injection Quantity Monitoring
Absent combustion sensors and/or pressure sensing glow plugs
mentioned above, there is currently no feedback sensor indicating that
the proper quantity of fuel has been injected. Therefore, injection
quantity monitoring will be more difficult than pressure monitoring.
Nonetheless, a manufacturer has identified a strategy currently being
used that verifies the injection quantity under very specific engine
operating conditions and appears to be capable of determining that the
system is accurately delivering the desired fuel quantity. This
strategy entails intrusive operation of the fuel injection system
during a deceleration event where fuel injection is normally shut off
(e.g., coasting or braking from a higher vehicle speed down to a low
speed or a stop). During the deceleration, fuel injection to a single
cylinder is turned back on to deliver a very small amount of fuel.
Typically, the amount of fuel would be smaller than, or perhaps
comparable to, the amount of fuel injected during a pilot or pre-
injection. If the fuel injection system is working correctly, that
known injected fuel quantity will generate a known increase in
fluctuations (accelerations) of the crankshaft that can be measured by
the crankshaft position sensor. If too little fuel is delivered, the
measured crankshaft acceleration will be smaller than expected. If too
much fuel is delivered, the measured crankshaft acceleration will be
larger than expected. This process can even be used to ``balance'' out
each cylinder or correct for system tolerances or deterioration by
modifying the commanded injection quantity until it produces the
desired crankshaft acceleration and applying a correction or adaptive
term to that cylinder's future injections. Each cylinder can, in turn,
be cycled through this process and a separate analysis can be made for
the performance of the fuel injection system for each cylinder. Even if
this procedure would require only one cylinder be tested per revolution
(to eliminate any change in engine operation or output that would be
noticeable to the driver) and require each cylinder to be tested on
four separate revolutions, this process would only take two seconds for
a six cylinder engine decelerating through 1500 rpm.
The crankshaft position sensor is commonly used to identify the
precise position of the piston relative to the intake and exhaust
valves to allow for very accurate fuel injection timing control and, as
such, there exists sufficient resolution and data sampling within the
onboard computer to enable such measurement of crankshaft
accelerations. Further, in addition to the current use of this strategy
in an under 14,000 pound diesel application, a nearly identical
crankshaft fluctuation technique has been used since 1997 on under
14,000 pound diesel engines
[[Page 3257]]
during idle conditions to determine if individual cylinders are
misfiring.
Another technique that may be used to achieve the same monitoring
capability is some variation on the current cylinder balance tests used
by many manufacturers to improve idle quality. In such strategies,
fueling to individual cylinders is increased, decreased, or shut off to
determine if the cylinder is contributing an equal share to the output
of the engine. This strategy again relies on changes in crankshaft/
engine speed to measure the individual cylinder's contribution relative
to known good values and/or the other cylinders. Such an approach seems
viable to determine whether the fuel injection quantity is correct for
each cylinder, but it has the disadvantage of not necessarily being
able to verify whether the system is able to deliver small amounts of
fuel precisely (such as those commanded during a pilot injection).
One other approach that has been mentioned but not investigated
thoroughly is the use of a wide-range air-fuel (A/F) sensor in the
exhaust to confirm fuel injection quantity. The A/F sensor output could
be compared to the measured air going into the engine and calculated
fuel quantity injected to see if the two agree. Differences in the
comparison may allow for the identification of incorrect fuel injection
quantity.
c. Fuel Injection Timing Monitoring
In the same manner as described for quantity monitoring, we believe
that fuel injection timing could be verified. By monitoring the
crankshaft speed fluctuation and, most notably, the time at which such
fluctuation begins, ends, or reaches a peak, the OBD system could
compare the time to the commanded fuel injection timing point and
verify that the crankcase fluctuation occurred within an acceptable
time delay relative to the commanded fuel injection. If the system was
working improperly and actual fuel injection was delayed relative to
when it was commanded, the corresponding crankshaft speed fluctuation
would also be delayed and would result in a longer than acceptable time
period between commanded fuel injection timing and crankshaft speed
fluctuation. A more detailed discussion of this possible monitoring
method is presented in the technical support document contained in the
docket.\58\
---------------------------------------------------------------------------
\58\ Draft Technical Support Document, HDOBD NPRM, EPA420-D-06-
006, Docket ID EPA-HQ-OAR-2005-0047-0008.
---------------------------------------------------------------------------
Another possible monitoring method that has been mentioned but not
investigated thoroughly would be to look for an electrical feedback
signal from the injector to the computer to confirm when the injection
occurred. Such a technique would likely use an inductive signature to
identify exactly when an injector opened or closed and verify that it
was at the expected timing. We expect that further investigation would
be needed to confirm that such a monitoring technique would be
sufficient to verify fuel injection timing.
d. Fuel System Feedback Control Monitoring
The conditions necessary for feedback control (i.e., the feedback
enable criteria) are defined as part of the control strategy in the
engine computer. The feedback enable criteria are typically based on
minimum conditions necessary for reliable and stable feedback control.
When the manufacturer is designing and calibrating the OBD system, the
manufacturer would determine, for the range of in-use operating
conditions, the time needed to satisfy these feedback enable criteria
on a properly functioning engine. In-use, the OBD system would evaluate
the time needed for these conditions to be satisfied following an
engine start, compare that to normal behavior for the system, and
indicate a malfunction when the time exceeds a specified value (i.e.,
the malfunction criterion). For example, fuel pressure feedback control
may be calibrated to begin once fuel system pressure has reached a
minimum specified value. In a properly functioning system, pressure
builds in the system during engine cranking and shortly after starting
and the pressure enable criterion are reached within a few seconds.
However, in a malfunctioning system (e.g., due to a faulty low-pressure
fuel pump), it may take a significantly longer time to reach the
feedback enable pressure. A malfunction would be indicated when the
actual time to reach feedback enable pressure exceeds the malfunction
criterion.
Malfunctions that cause open-loop or default operation can be
readily detected as well. As discussed above, the feedback enable
criteria are clearly defined in the computer and are based on what is
necessary for reliable control. After feedback control has begun, the
OBD system can detect these criteria and indicate a malfunction when
they are no longer being satisfied. For example, one enable criterion
could be a pressure sensor reading within a certain range where the
upper pressure limit would be based on the maximum pressure that could
be generated in a properly functioning system. A malfunction would be
indicated if the pressure sensor reading exceeded the upper limit which
would cause the fuel system to go open loop.
The feedback control system adjusts the base fuel strategy such
that actual engine operating characteristics meet driver demand. But,
the feedback control system has limits on how much adjustment can be
made based, presumably, on the ability to maintain acceptable control.
Like the feedback enable criteria, these control limits are defined in
the computer. The OBD system would track the actual adjustments made by
the control system and continuously compare them with the control
limits. A malfunction would be indicated if the limits were reached.
2. Engine Misfire Monitoring
Diesel engines certified to the under 14,000 pound OBD requirements
have been monitoring for misfire since the 1998 model year. The
monitoring requirements we are proposing for over 14,000 pound
applications are identical to the existing requirements for under
14,000 pound applications for those engines that do not use combustion
sensors.\59\ Therefore, technological feasibility has been demonstrated
for these applications.
---------------------------------------------------------------------------
\59\ Technically, the EPA OBD diesel misfire monitoring
requirement for under 14,000 pound applications is to detect a lack
of combustion whereas the California OBDII diesel misfire monitoring
requirement is identical to what we are proposing for over 14,000
pounds. Since all manufacturers to date are designing to the OBDII
requirements, this statement is, for practical purposes, true.
---------------------------------------------------------------------------
For engines that use combustion sensors, the misfire monitoring
requirements are more stringent since the requirement calls for
detection of malfunctions causing emissions to exceed the emissions
thresholds. Nonetheless, detection on these engines should be straight
forward since the combustion sensors would provide a direct measurement
of combustion. Therefore, lack of combustion (i.e., misfire) could be
measured directly. The combustion sensors are intended to measure
various characteristics of a combustion event for feedback control.
Such feedback is needed for engines that require very precise air and
fuel metering controls such as would be required for homogeneous charge
compression ignition (HCCI) engine. Accordingly, the resolution of
sensors having that capability is well beyond what would be needed to
detect a complete lack of combustion.
[[Page 3258]]
3. Exhaust Gas Recirculation (EGR) Monitoring
a. EGR Low Flow/High Flow Monitoring
Typically, the EGR control system determines a desired EGR flow
rate based on the engine operating conditions such as engine speed and
engine load. The desired EGR flow rates, and the corresponding EGR
valve positions needed to achieve the desired flow rates, are
established when the manufacturer designs and calibrates the EGR
system. Once established, manufacturers store the desired EGR flow
rate/valve position in a lookup table in the onboard computer. During
operation, the onboard computer commands the EGR valve to the position
necessary to achieve the desired flow--i.e., the commanded EGR flow.
The onboard computer then calculates or directly measures both the
fresh air charge (fresh air intake) and total intake charge. The
difference between the total intake charge and fresh air intake is the
actual EGR flow. The closed-loop control system continuously adjusts
the EGR valve position until the actual EGR flow equals the desired EGR
flow.
Such closed-loop control strategies and their associated OBD
monitoring strategies are used on many existing gasoline and diesel
vehicles under 14,000 pounds. The OBD system evaluates the difference
(i.e., error) between the look-up value--i.e., the desired flow rate--
and the final commanded value needed to achieve the desired flow rate.
Typically, as the feedback parameter or learned offset increases, there
is an attendant increase in emissions. A correlation can be made
between feedback adjustment and emissions. When the error exceeds a
specific threshold, a malfunction would be indicated. This type of
monitoring strategy could be used to detect both high and low flow
malfunctions.
While the closed-loop control strategy described above is effective
in measuring and controlling EGR flow, some manufacturers are currently
investigating the use of a second control loop based on an air-fuel
ratio (A/F) sensor (also known as wide-range oxygen sensors or linear
oxygen sensors) to further improve EGR control and emissions. With this
second control loop, the desired air-fuel ratio is calculated based on
engine operating conditions (i.e., intake airflow, commanded EGR flow
and commanded fuel). The calculated air-fuel ratio is compared to the
air-fuel ratio from the A/F sensor and refinements can be made to the
EGR and airflow rates--i.e., the control can be ``trimmed''--to achieve
the desired rates. On systems that use the second control loop, flow
rate malfunctions could also be detected using the feedback information
from the A/F sensor and by applying a similar monitoring strategy as
discussed above for the primary EGR control loop.
We are also proposing that two leaking EGR valve failure modes be
detected. One type is the failure of the valve to seal when in the
closed position. For example, if the valve or seating surface is
eroded, the valve could close and seat, yet still allow some flow
across the valve. A flow check is necessary to detect a malfunctioning
valve that closes properly but still leaks. EGR flow--total intake
charge minus fresh air charge--could be calculated using the monitoring
strategy described above for high and low flow malfunctions. With the
valve closed, a malfunction would be indicated when flow exceeds
unacceptable levels. Or, some cooled EGR systems will incorporate an
EGR temperature sensor that could be used to detect a leaking EGR valve
by reacting to the presence of hot exhaust gases when none should be
present. A leaking valve can also be caused by failure of the valve to
close/seat. For example, carbon deposits on the valve or seat could
prevent the valve from closing fully. The flow check described above
could detect failure of the valve to close/seat, but this approach
would require a repair technician to further diagnose whether the
problem is a sealing or seating problem. Such a failure of the valve to
close/seat could be more specifically monitored by closing the valve
and checking the zero position of the valve with a position sensor. If
the valve position is out of the acceptable range for a closed valve, a
malfunction would be indicated. This type of zero position sensor check
is commonly used to verify the closed position of valves/actuators used
in gasoline OBD systems (e.g. gasoline EGR valves, electronic throttle)
and should be feasible for diesel EGR valves.
b. EGR Slow Response Monitoring
While the flow rate monitor discussed above would evaluate the
ability of the EGR system to achieve a commanded flow rate under
relatively steady state conditions, the EGR slow response monitor would
evaluate the ability of the EGR system to modulate (i.e., increase and
decrease) EGR flow as engine operating conditions and, consequently,
commanded EGR rates change. Specifically, as engine operating
conditions and commanded EGR flow rates change, the monitor would
evaluate the time it takes for the EGR control system to achieve the
commanded change in EGR flow. This monitor could evaluate EGR response
passively during transient engine operating conditions encountered
during in-use operation. The monitor could also evaluate EGR response
intrusively by commanding a change in EGR flow under a steady state
engine operating condition and measuring the time it takes to achieve
the new EGR flow rate. Similar passive and intrusive strategies have
been developed for variable valve control and/or timing (VVT)
monitoring on vehicles under 14,000 pounds.
c. EGR Feedback Control Monitoring
Monitoring of EGR feedback control could be performed using
analogous strategies to those discussed in Section III.A.1 for
monitoring of fuel system feedback control.
d. EGR Cooling System Monitoring
Some diesel engine manufacturers currently use exhaust gas
temperature sensors as an input to their EGR control systems. On such
systems--EGR temperature--which is measured downstream of the EGR
cooler--could be used to monitor the effectiveness of the EGR cooler.
For a given engine operating condition (e.g., a steady speed/load that
generates a known exhaust mass flow and exhaust temperature to the EGR
cooler), EGR temperature will increase as the performance of the EGR
cooling system decreases. During the OBD calibration process,
manufacturers could develop a correlation between increased EGR
temperatures and cooling system performance (i.e., increased
emissions). The EGR cooling system monitor would use such a correlation
and indicate a malfunction when the EGR temperature increases to the
level that would cause emissions to exceed the emissions thresholds.
While we anticipate that most, if not all, manufacturers will use
EGR temperature sensors to meet future emissions standards, EGR cooling
system monitoring may be feasible without such a temperature sensor.
The monitor could be done using the intake manifold temperature (IMT)
sensor by looking at the change in IMT (i.e., ``delta'' IMT) with EGR
turned on and EGR turned off (IMT would be higher with EGR turned on).
If there is significant cooling capacity with a normally functioning
EGR cooling system, there would likely be a significant difference in
IMT with EGR turned on versus turned off. Delta IMT could be correlated
to decreased EGR cooling system performance and increased emissions.
[[Page 3259]]
4. Turbo Boost Control System Monitoring
a. Turbo Underboost/Overboost Monitoring
To monitor boost control systems, manufacturers are expected to
look at the difference between the actual pressure sensor reading (or
calculation thereof) and the desired/target boost pressure. If the
error between the two is too large or persists for too long, a
malfunction would be indicated. Manufacturers would need to calibrate
the size of error and/or error duration to ensure robust malfunction
detection occurs before the emissions thresholds are exceeded. Given
that the purpose of a closed-loop control system with a feedback sensor
is to measure continuously the difference between actual and desired
boost pressure, the control system is already monitoring that
difference and attempting to minimize it. As such, a monitoring
requirement to indicate a malfunction when the difference gets large
enough such that it can no longer achieve the desired boost is
essentially an extension of the existing control strategy.
To monitor for malfunction or deterioration of the boost pressure
sensors, manufacturers could validate sensor readings against other
sensors present on the vehicle or against ambient conditions. For
example, at initial key-on before the engine is running, the boost
pressure sensor should read ambient pressure. If the vehicle is
equipped with a barometric pressure sensor, the two sensors could be
compared and a malfunction indicated when the two readings differ
beyond the specific tolerances. A more crude rationality check of the
boost pressure sensor could be accomplished by verifying that the
pressure reading is within reasonable atmospheric limits for the
conditions the vehicle will be subjected to.
b. VGT Slow Response Monitoring
The VGT slow response monitor would evaluate the ability of the VGT
system to modulate (i.e., increase and decrease) boost pressure as
engine operating conditions and, consequently, commanded boost pressure
changes. Specifically, as engine operating conditions and commanded
boost pressures change, the monitor would evaluate the time it takes
for the VGT control system to achieve the commanded change in boost
pressure. This monitor could evaluate VGT response passively during
transient engine operating conditions encountered during in-use
operation. The monitor could also evaluate VGT response intrusively by
commanding a change in boost pressure under a steady state engine
operating condition and measuring the time it takes to achieve the new
boost pressure.
Rationality monitoring of VGT position sensors could be
accomplished by comparing the measured sensor value to expected values
for the given engine speed and load conditions. For example, at high
engine speeds and loads, the position sensor should indicate that the
VGT position is opened more than would be expected at low engine speeds
and loads. Such rationality checks would need to be two-sided (i.e.,
position sensors should be checked for appropriate readings at both
high and low engine speed/load operating conditions.
c. Turbo Boost Feedback Control Monitoring
Monitoring of boost pressure feedback control could be performed
using analogous strategies to those discussed for fuel system feedback
control monitoring in Section III.A.1.
d. Charge Air Undercooling Monitoring
We expect that most engines will make use of a temperature sensor
downstream of the charge air cooler to protect against overcooling
conditions that could cause excessive condensation, and to prevent
undercooling that could result in loss of performance. A comparison of
the actual charge air temperature to the expected, or design,
temperature would indicate any errors that might be occurring.
Manufacturers could correlate that error to an emissions impact and,
when the error reached a level such that emissions would exceed the
emissions thresholds, a malfunction would be indicated.
5. Non-Methane Hydrocarbon (NMHC) Converting Catalyst Monitoring
a. NMHC Converting Catalyst Conversion Efficiency Monitoring
Monitoring of the NMHC converting catalyst, or diesel oxidation
catalyst (DOC), could be performed similar to three-way catalyst
monitoring on gasoline engines. Three-way catalyst monitoring uses the
concept that catalyst's oxygen storage capacity correlates well with
its hydrocarbon conversion efficiency. Oxygen sensors located upstream
and downstream of the catalyst can be used to determine when its oxygen
storage capacity--and, hence, its conversion efficiency--has
deteriorated below a predetermined level.
Determining the oxygen storage capacity would require lean air-fuel
(A/F) operation followed by rich A/F operation or vice-versa during the
catalyst monitoring event. Since a diesel engine normally operates lean
of stoichiometry, lean A/F operation would be normal operation.
However, rich A/F operation would have to be commanded intrusively when
the catalyst monitor is active. The rich A/F operation could be
achieved by injecting some fuel late enough in the four stroke process
(i.e., late injection) that the raw fuel would not combust in-cylinder.
Rich A/F operation could also be achieved using an in-exhaust fuel
injector upstream of the catalyst. During normal lean operation, the
catalyst would become saturated with stored oxygen. As a result, both
the front and rear oxygen sensors should be reading lean. When rich A/F
operation initiates, the front oxygen sensor would switch immediately
to a ``rich'' indication. For a short time, the rear oxygen sensor
should continue to read ``lean'' until such time as the stored oxygen
in the catalyst is consumed by the rich fuel mixture in the exhaust and
the rear oxygen sensor would read ``rich.'' As the catalyst
deteriorates, the delay time between the front and rear oxygen sensors
switching from their normal lean state to a rich state would become
progressively smaller because the deteriorated catalyst would have less
oxygen storage capacity. Thus, by comparing the time difference between
the responses of the front and rear oxygen sensors to the lean-to-rich
or rich-to-lean A/F changes, the performance of the catalyst could be
estimated. Although this discussion suggests the use of conventional
oxygen sensors, these sensors could be substituted with A/F sensors
which would also provide for additional engine control benefits such as
EGR trimming and fuel trimming.
If a malfunction of the catalyst cannot cause emissions to exceed
the emissions thresholds, then only a functional monitor would be
required. A functional monitor could be done using temperature sensors.
A functioning oxidation catalyst would be expected to provide some
level of exotherm when it oxidizes HC and CO. The temperature of the
catalyst could be measured by placing one or more temperature sensors
at or near the catalyst. However, depending on the nominal conversion
efficiency of the catalyst and the duty cycle of the vehicle, the
exotherm may be difficult to discern from the inlet exhaust
temperatures. To add robustness to the monitor, the functional monitor
would need to be conducted during predetermined
[[Page 3260]]
operating conditions where the amount of HC and CO entering the
catalyst could be known. This may require an intrusive monitor that
actively forces the fueling strategy richer (e.g., through late or post
injection) than normal for a short period of time. If the measured
exotherm does not exceed a predetermined amount that only a properly-
working catalyst could achieve, a malfunction would be indicated. As
noted, such an approach would require a brief period of commanded rich
operation that would result in a very brief HC and perhaps a PM
emissions spike.
b. Other Aftertreatment Assistance Function Monitoring
A functional monitor should be sufficient for monitoring the
oxidation catalyst's ability to fulfill aftertreatment assistance
functions such as generating an exotherm for DPF regeneration or
providing a proper feedgas for SCR or NOX adsorbers. We
would expect that manufacturers would use the exotherm approach
mentioned above either to measure directly for the proper exotherm or
to correlate indirectly for the proper feedgas. For catalysts upstream
of a DPF, we expect that this monitoring would be conducted during an
active or forced regeneration event.\60\ For catalysts downstream of
the DPF, we expect that manufacturers would have to add fuel
intrusively (either in-exhaust or through in-cylinder post-injection)
to create a sufficient exotherm to distinguish malfunctioning from
properly operating catalysts.
---------------------------------------------------------------------------
\60\ An active or forced regeneration would be those
regeneration events that are initiated via a driver selectable
switch or activator and/or those initiated by computer software.
---------------------------------------------------------------------------
6. Selective Catalytic Reduction (SCR) and NOX Conversion
Catalyst Monitoring
a. SCR and NOX Catalyst Conversion Efficiency Monitoring
We would expect manufacturers to use NOX sensors to
monitor a lean NOX catalyst. NOX sensors placed
upstream and downstream of the lean NOX catalyst could be
used to determine directly the NOX conversion efficiency.
Manufacturers could potentially use a single NOX sensor
placed downstream of the catalyst to measure catalyst-out
NOX emissions. This would have to be done within a tightly
controlled engine operation window where engine-out NOX
emissions (i.e., NOX emissions at the lean NOX
catalyst inlet) performance is relatively stable and could be estimated
reliably. Within this engine operation window, catalyst-out
measurements could be compared to the expected engine-out
NOX emissions and a catalyst conversion efficiency could be
calculated. Should the calculated conversion efficiency be insufficient
to maintain emissions below the emissions thresholds, a malfunctioning
or deteriorated lean NOX catalyst would be indicated. If
both an upstream and downstream NOX sensor are used for
monitoring, the upstream sensor could be used to improve the overall
effectiveness of the catalyst by precisely controlling the air-fuel
ratio in the exhaust to the levels where the catalyst is most
effective.
For monitoring the SCR catalyst, care must be taken to account for
the cross sensitivity of NOX sensors to ammonia
(NH3). Current NOX sensor technology tends to
have such a cross-sensitivity to ammonia in that as much as 65 percent
of ammonia can be read as NOX.\61\ However, urea SCR
feedback control studies have shown that the NH3
interference signal is discernable from the NOX signal and
can, in effect, allow the design of a better feedback control loop than
a NOX sensor that doesn't have any NH3 cross-
sensitivity. In one study, a signal conditioning method was developed
that resulted in a linear output for both NH3 and
NOX from the NOX sensor downstream of the
catalyst.\62\ Monitoring of the catalyst can be done by using the same
NOX sensors that are used for SCR control. When the SCR
catalyst is functioning properly, the upstream sensor should read
``high'' for high NOX levels while the downstream sensor
should read ``low'' for low NOX and low ammonia levels. With
a deteriorated SCR catalyst, the downstream sensor should read similar
or higher values as the upstream sensor (i.e., high NOX and
high ammonia levels) since the NOX reduction capability of
the catalyst has diminished. Therefore, a malfunctioning SCR catalyst
could be detected when the downstream sensor output is near to or
greater than the upstream sensor output. A similar monitoring approach
could be used if a manufacturer models upstream NOX
emissions instead of using an upstream NOX sensor. In this
case, the comparison would be made between the modeled upstream
NOX value and the downstream sensor value.
---------------------------------------------------------------------------
\61\ Schaer, C.M., Onder, C.H., Geering, H.P., and Elsener, M.,
``Control of a Urea SCR Catalytic Converter System for a Mobile
Heavy-Duty Diesel Engine,'' SAE Paper 2003-01-0776 which may be
obtained from Society of Automotive Engineers International, 400
Commonwealth Dr., Warrendale, PA, 15096-0001.
\62\ Ibid.
---------------------------------------------------------------------------
Manufacturers have expressed concern over both the sensitivity and
the durability of NOX sensors. They are concerned that
NOX sensors will not have the necessary sensitivity to
detect NOX at the low levels that will exist downstream of
the NOX catalyst. They are also concerned that
NOX sensors will not be durable enough to last the full
useful life of big diesel trucks. We have researched NOX
sensors--the current state of development and future expectations--and
summarized our findings in the technical support document in the docket
for this rule.\63\ Some of our findings are summarized here.
---------------------------------------------------------------------------
\63\ Draft Technical Support Document, HDOBD NPRM, EPA420-D-06-
006, Docket ID EPA-HQ-OAR-2005-0047-0008.
---------------------------------------------------------------------------
Regarding NOX sensor sensitivity, we expect that 2010
and later model year engines will have average tailpipe NOX
emissions in the 0 to 50 ppm range. Current NOX sensors have
an accuracy of 10 ppm in the 0 to 100 ppm range. This means
that current NOX sensors should be able to detect
NOX emissions that exceed the standard by two to three times
the 2010 limit.\64\ This should allow for compliance with our proposed
threshold which is effectively 2.5 times the 2010 limit. Further, we
expect that NOX sensors in the 0 to 100 ppm range with
5 ppm accuracy will be available by the middle of 2006.
Regarding durability, improvements are being made and a test program is
currently underway with the intent of aging several NOX
sensors placed at various exhaust system locations out to 6,000 hours
(roughly equivalent to 360,000 miles). Results after 2,000 hours of
aging are promising and results after 4,000 hours of aging are
currently being analyzed.\65\
---------------------------------------------------------------------------
\64\ Ibid.
\65\ Ibid.
---------------------------------------------------------------------------
b. SCR and NOX Catalyst Active/Intrusive Reductant Injection
System Monitoring
If an active catalyst system is used--i.e., one that relies on
injection of a reductant upstream of the catalyst to assist in
emissions conversion--manufacturers would be required to monitor the
mechanism for adding the fuel reductant. In the active catalyst system,
a temperature sensor is expected to be placed near or at the catalyst
to determine when the catalyst temperature is high enough to convert
emissions. Because NOX catalyst systems, especially lean
NOX catalyst systems, tend to have a narrow temperature
range where they are most effective, adding reductant when the catalyst
temperature is not sufficiently high would waste reductant. If fuel is
[[Page 3261]]
used as the reductant, this would adversely affect fuel economy without
a corresponding reduction in emissions levels. Therefore, a temperature
sensor is expected to be placed in the exhaust near or at the catalyst
to help determine when reductant injection should occur. This same
sensor could be used to determine if an exotherm resulted following
reductant injection. The lack of an exotherm would indicate a
malfunction of the reductant delivery system.
Alternatively, any NOX sensors used to monitor
conversion efficiency could be used to determine if reductant injection
has occurred. NOX sensors are also oxygen sensors so they
could be used to determine the air-fuel ratio in the exhaust stream
which would allow for verification of reductant injection into the
exhaust. Further, with a properly functioning injector, the downstream
NOX sensor should see a change from high NOX
levels to low NOX levels. In contrast, a lack of reductant
injection would result in continuously high NOX levels at
the downstream NOX sensor. Therefore, a malfunctioning
injector could be indicated when the downstream NOX sensor
continues to measure high NOX after an injection event has
been commanded.
Reductant level monitoring could also be conducted by using the
existing NOX sensors that are used for control purposes.
Specifically, the downstream NOX sensor can be used to
determine if the reductant tank no longer has sufficient reductant
available. Similar to the fuel reductant injection functionality
monitor described above, when the reductant tank has a sufficient
reductant quantity and the injection system is working properly, the
downstream NOX sensor should see a change from high
NOX levels to low NOX levels. If the
NOX levels remain constant both before and after reductant
injection, then the reductant was not properly delivered and either the
injection system is malfunctioning or there is no longer sufficient
reductant available in the reductant tank. Alternatively, reductant
level monitoring could be conducted by using a dedicated ``float'' type
level sensor similar to the ones used in fuel tanks. Some manufacturers
may prefer using a dedicated reductant level sensor in the reductant
tank to inform the vehicle operator of current reductant levels via a
gauge on the instrument panel. If such a sensor is used by the
manufacturer for operator convenience, it could also be used to monitor
the reductant level in the tank.
Monitoring the reductant itself--whether it be the wrong reductant
or a poor quality reductant--could also be conducted using the
NOX sensors used for control purposes. If an improper
reductant is injected, the NOX catalyst system would not
function properly. Therefore, NOX emissions downstream from
the catalyst would remain high both before and after injection. The
downstream NOX sensor would see the high NOX
levels after injection and a malfunction would be indicated. If the
reductant tank level sensor indicated sufficient levels for injection
and decreasing levels following injections (which would mean the
injection system was working), then the probable cause of the
malfunction would be the reductant itself. For urea SCR systems,
another possible means of monitoring the reductant itself would be to
use a urea quality sensor in the urea tank. First generation sensors
show promise at verifying that urea is indeed in the tank, rather than
water or some other fluid, and that the urea concentration is within
the needed range (i.e., not diluted with water or some other fluid).
The sensor could also be used in place of a urea level sensor. By 2010,
we would expect subsequent generation sensors to provide even better
capability.\66\
---------------------------------------------------------------------------
\66\ Crawford, John M., Mitsui Mining & Smelting Co., Ltd.,
presentation to EPA, October 2006, Docket ID EPA-HQ-OAR-
2005-0047-0007.
---------------------------------------------------------------------------
c. SCR and NOX Catalyst Feedback Control Monitoring
Monitoring of feedback control could be performed using analogous
strategies to those discussed for fuel system feedback control
monitoring in Section III.A.1.
7. NOX Adsorber Monitoring
a. NOX Adsorber Capability Monitoring
We expect that either NOX sensors or A/F sensors along
with a temperature sensor will be used to provide the feedback
necessary to control the NOX adsorber system. These same
sensors could also be used to monitor the NOX adsorber
system's capability. The use of NOX sensors placed upstream
and downstream of the adsorber system would allow the system's
NOX reduction performance to be continuously monitored. For
example, the upstream NOX sensor on a properly functioning
adsorber system operating with lean fuel mixtures, will read high
NOX levels while the downstream NOX sensor should
read low NOX levels. With a deteriorated NOX
adsorber system, the upstream NOX levels will continue to be
high while the downstream NOX levels will also be high.
Therefore, a malfunction of the system can be detected by comparing the
NOX levels measured by the downstream NOX sensor
versus the upstream sensor.
The possibility exists that an upstream NOX sensor will
not be used for NOX adsorber control. Manufacturers may
choose to model engine-out NOX levels--based on engine
operating parameters such as engine speed, fuel injection quantity and
timing, EGR flow rate--thereby eliminating the need for the upstream
NOX sensor. In this case, we believe that monitoring of the
system could be conducted using A/F sensors in place of NOX
sensors.\67\ During lean engine operation with a properly operating
NOX adsorber system, both the upstream and downstream A/F
sensors would indicate lean mixtures. When the exhaust gas is
intrusively commanded rich to regenerate the NOX adsorber,
the upstream A/F sensor would quickly indicate a rich mixture while the
downstream sensor should continue to see a lean mixture due to the
chemical reaction of the reducing agents with NOX and oxygen
stored on the adsorber. Once all of the stored NOX and
oxygen has been released, the reducing agents in the exhaust would
cause the downstream A/F sensor to indicate a rich reading. The more
NOX that is stored in the adsorber, the longer the delay
between the rich indications from the upstream and downstream sensors.
Thus, the time differential between the rich indications from the
upstream and downstream A/F sensors is a gauge of the NOX
storage capacity of the adsorber. This delay could be correlated to an
emissions increase and the monitor could be calibrated to indicate a
malfunction upon detecting an unacceptably short delay. In fact, Honda
currently uses a similar approach to monitor the NOX
adsorber on a 2003 model year gasoline vehicle which demonstrates the
viability of the approach in a shorter lived application. We have
studied A/F sensors and their durability with respect to longer lived
diesel applications and our results are summarized in a report placed
in the docket to this rule.\68\
---------------------------------------------------------------------------
\67\ Ingram, G.A. and Surnilla, G., ``On-Line Estimation of
Sulfation Levels in a Lean NOX Trap,'' SAE Paper 2002-01-
0731 may be obtained from Society of Automotive Engineers
International, 400 Commonwealth Dr., Warrendale, PA 15096-0001.
\68\ Draft Technical Support Document, HDOBD NPRM, EPA420-D-06-
006, Docket ID EPA-HQ-OAR-2005-0047-0008.
---------------------------------------------------------------------------
[[Page 3262]]
b. NOX Adsorber Active/Intrusive Reductant Injection System
Monitoring
The injection system used to achieve NOX regeneration of
the NOX adsorber could also be monitored with A/F sensors.
When the control system injects extra fuel to achieve a rich mixture,
the upstream A/F sensor would respond to the change in fueling and
could measure directly whether or not the proper amount of fuel had
been injected. If manufacturers employ a NOX adsorber system
design that uses only a single A/F sensor downstream of the adsorber,
that downstream sensor could be used to monitor the performance of the
injection system. As discussed above, the downstream sensor would
switch from a lean reading to a rich reading when the stored
NOX has been completely released and reduced. If the sensor
switches too quickly after rich fueling is initiated, then either too
much fuel has been injected or the adsorber itself has poor storage
capability. Conversely, if the sensor takes too long to switch after
rich fueling is initiated, it may be an indication that the adsorber
has very good storage capability. However, excessive switch times
(i.e., times that exceed the maximum storage capability of the
adsorber) could be indicative of an injection system malfunction (i.e.,
insufficient fuel has been injected) or a sensor malfunction (i.e., the
sensor has a slow response).
c. NOX Adsorber Feedback Control Monitoring
Monitoring of feedback control could be performed using analogous
strategies to those discussed for fuel system feedback control
monitoring in Section III.A.1.
8. Diesel Particulate Filter (DPF) Monitoring
a. PM Filtering Performance Monitoring
The PM filtering performance monitor is perhaps the monitor for
which we have the most concern with respect to feasibility. Part of
this concern stems from the difficulty in detecting the very low PM
emissions levels required for 2007/2010 engines (i.e., 0.01 g/bhp-hr).
While we have made changes to our test procedures that will allow for
more accurate measurement of PM in the test cell, it is still very
difficult to do. With today's proposal, we are expecting manufacturers
to detect failures in the filtering performance of only a few times the
actual standards. Success at doing so presents a very difficult
challenge to manufacturers. Our concerns, in part, have led us to
propose a different 2013 and later emissions threshold for this monitor
than that proposed by ARB. This was discussed in more detail in section
I.D.2.
We anticipate that manufacturers can meet the proposed PM filtering
monitor requirements without adding hardware other than that used for
control purposes. We believe that the same pressure and temperature
sensors that are used to control DPF regeneration will be used for OBD
monitoring. For control purposes, manufacturers generally use a
differential or delta pressure sensor placed across the DPF and at
least one temperature sensor located near the DPF. The differential
pressure sensor is expected to be used on DPF systems to prevent damage
that could be caused by delayed or incomplete regeneration. Such
conditions could lead to excessive temperatures and melting of the DPF
substrate. When the differential pressure exceeds a predetermined
level, a regeneration event would be initiated to burn the trapped PM.
However, engine manufacturers have told us that differential
pressure alone does not provide a robust indication of trapped PM in
the DPF. For example, most if not all DPFs in the 2010 timeframe will
be catalyzed DPFs that are designed to regenerate passively during most
operation. Sometimes, conditions will not permit the passive
regeneration and an active regeneration would have to be initiated.
Relying solely on the differential pressure sensor to determine when an
active regeneration event was necessary would not be sufficient. A low
differential pressure could mean a low PM load and could also mean a
leaking DPF substrate. A high differential pressure could mean a high
PM load and could also mean a melted substrate. In the latter case, the
system may continually attempt to regenerate the DPF despite a low PM
load which would both waste fuel and increase HC emissions.
As a result, manufacturers will probably use some sort of soot-
loading model to predict the PM load on the DPF as part of their
regeneration strategy. Without a robust prediction, a regeneration
event could be initiated too early (i.e., when too little PM was
present which would be a waste of fuel and would increase HC emissions)
or too late (i.e., when too much PM has been allowed to build and the
regeneration event could cause a meltdown of the substrate). The model
would estimate the PM load by tracking the difference between the
modeled engine-out PM (i.e., the emissions that are being loaded on the
DPF) and regenerated PM (i.e., the PM that is being burned off the DPF
due to passive and/or active regenerations).
Given this, we believe that a comprehensive and accurate soot-
loading model is also necessary for successful monitoring of DPF
filtering performance. The model would predict the PM load on the DPF
based on fuel consumption and engine operating conditions and would
predict passively regenerated PM based on temperatures. This predicted
PM load would be compared to the measured PM load taken from the
differential pressure sensors. Differences would correspond to either a
leaking substrate (i.e., predicted load greater than measured load) or
melting of the substrate faceplate (i.e., measured load greater than
predicted load).
Nonetheless, much development remains to be done and success is not
guaranteed. Manufacturers have noted that a melted substrate through
which a large channel has opened could have differential pressure
characteristics identical to a good substrate despite allowing most of
the engine-out PM to flow directly through. We agree that this is a
difficult failure mode and have proposed language that would allow
certification of DPF monitors that are unable to detect it. Possibly, a
temperature sensor in the DPF could detect the extreme temperatures
capable of causing such a severe substrate melting. Upon detecting such
a temperature, a regeneration event could be initiated to burn off any
trapped PM. Following that event, the soot model would expect a certain
increase in differential pressure based on modeled engine-out PM and
passive regeneration characteristics. Presumably, the measured
differential pressure profile would not match the predicted profile
because most PM would be flowing straight through the melted channel.
This same approach, or perhaps a simple temperature sensor, should
quite easily be able to detect a missing substrate.
Lastly, manufacturers have noted their concern that small
differences in substrate crack size or location may generate large
differences in tailpipe emission levels. They have also noted their
lack of confidence that they will be able to reliably detect all leaks
that would result in emissions exceeding the proposed thresholds.
Accordingly, the manufacturers have suggested pursuing an alternate
malfunction criterion independent of emission level. They have
suggested criteria such as a percent of exhaust flow leakage or a
specific leak or hole size that must be detected. We believe that
pursuit of such alternate thresholds would not be appropriate at this
time. Manufacturers have not yet completed work on initial widespread
[[Page 3263]]
implementation of DPFs for the 2007 model year. We expect that during
the year or two following that implementation, substantial refinement
and optimization will occur based on field experiences and that
correlation of sensor readings to emissions levels will be possible for
at least some DPF failure modes by the 2010 model year.
b. DPF Regeneration Monitoring
Pressure sensing, in combination with the soot model, could also be
used to determine if regeneration is functioning correctly. After a
regeneration event, the differential pressure should drop significantly
since the trapped PM has been removed. If it does not drop to within
the soot model's predicted range after the regeneration event, either
the regeneration did not function correctly or the filter could have
excessive ash loading. Ash loading is a normal byproduct of engine
operation (the ash loading is largely a function of oil consumption by
the engine and the ash content of the engine oil). The ash builds up in
the DPF and does not burnout as does the PM but rather must be removed
or blown out of the DPF. Manufacturers are working with us to determine
the necessary maintenance intervals at which this ash removal will
occur. The soot model would have to account for ash buildup in the DPF
with miles or hours of operation. Future engine oils will have lower
ash content and have tighter quality control such that more accurate
predictions of ash loading will be possible. By including ash loading
in the soot model, we believe that its effects could be accounted for
in the predicted differential pressure following a regeneration event.
As stated, manufacturers are projected to make use of temperature
sensors for regeneration control. These same sensors could also be used
to monitor active regeneration of the filter. If excess temperatures
are seen by the temperature sensor during active regeneration, the
regeneration process can be stopped or slowed down to protect the
filter. If an active regeneration event is initiated and there a
temperature rise commensurate with the amount of trapped PM is not
detected, the regeneration system is not working and a malfunction
would be indicated.
c. DPF NMHC Conversion Efficiency Monitoring
Given the stringency of the 2010 standards, we believe that
manufactures may rely somewhat on the DPF to convert some of the HC
emissions. The proposed requirement requires monitoring this function
only if the system serves this function. We believe that, provided the
filtering performance and regeneration system monitors have not
detected any malfunctions, the NMHC conversion is probably working
fine. Given the level of the threshold, and the expectation that the
DPF will serve to control NMHC only marginally, we do not anticipate
this monitor needing emissions correlation work. Instead, we expect
that, with the DPF temperature sensor, it should be possible to infer
adequate NMHC conversion by verifying an exotherm. Nonetheless, if a
manufacturer relies so heavily on the DPF for NMHC conversion that its
ability to convert could be compromised to the point of emissions
exceeding the threshold, a more robust monitor may be required by
correlating exotherm levels to NMHC impacts.
d. DPF Regeneration Feedback Control Monitoring
Monitoring of DPF regeneration feedback control could be performed
using analogous strategies to those discussed for fuel system feedback
control monitoring in Section III.A.1.
9. Exhaust Gas Sensor Monitoring
The under 14,000 pound OBD regulations have required oxygen sensor
monitoring since the 1996 model year. Vehicles have been certified
during that time meeting the requirements. The technological
feasibility of monitoring oxygen sensors has been demonstrated.
Additionally, A/F sensor monitoring has been required, manufacturers
have complied, and the feasibility has been similarly demonstrated.
NOX sensors are a recent technology and, as such, they
are still being developed and improved. However, we would expect that
manufacturers would design their upstream NOX sensor
monitors to be similar the A/F sensor monitors used in under 14,000
pound applications. Monitoring of downstream sensors may require
modifications to existing A/F sensor strategies and/or new strategies.
Since NOX sensors are projected to be used only for control
and monitoring of aftertreatment systems that reduce NOX
emissions (e.g., SCR systems), the OBD system would have to distinguish
between deterioration of the aftertreatment system and the
NOX sensor itself. As the aftertreatment deteriorates,
NOX emissions downstream of the aftertreatment device will
increase and, assuming there is no such deterioration in the
NOX sensor, the NOX sensor will read these
increasing NOX levels. As discussed in sections III.A.6 and
III.A.7, the increased NOX levels can be the basis for
monitoring the performance of the aftertreatment system. However, if
the NOX sensor does deteriorate with the aftertreatment
device (i.e., its response rate slows with mileage/operating hours),
the sensor may not properly read the increasing NOX levels
from the deteriorating aftertreatment system, and the aftertreatment
monitor might conclude that the aftertreatment system is functioning
properly. Similarly, the performance or level of deterioration of the
NOX aftertreatment device could affect the results of the
NOX sensor monitor. Therefore to achieve robust monitoring
of aftertreatment and sensors, the OBD system has to distinguish
between deterioration of the aftertreatment system and deterioration of
the NOX sensor. To properly monitor the NOX
sensor, the sensor monitor has to run under conditions where the
aftertreatment performance can be quantified and compensated for or
eliminated in the monitoring results.
For example, the effects of the SCR performance could be eliminated
by monitoring the NOX sensor under a steady-state operating
condition during which engine-out NOX emissions were stable.
Under a relatively steady-state condition, reductant injection could be
``frozen'' (i.e., the reductant injection quantity could be held
constant) which would also freeze the conversion efficiency of the SCR
system. With SCR performance held constant, engine-out NOX
emissions could be intrusively increased by a known amount (e.g., by
reducing EGR flow or changing fuel injection timing and allowing the
engine-out NOX model to determine the increase in
emissions). The resulting increase in emissions would pass through the
SCR catalyst unconverted, and the sensor response to the known increase
in NOX concentrations could be measured and evaluated. This
strategy could be used to detect both response malfunctions (i.e., the
sensor reads the correct NOX concentration levels but the
sensor reading does not change fast enough to keep up with changing
exhaust NOX concentrations) and rationality malfunctions
(i.e., the sensor reads the wrong NOX level). Rationality
malfunctions could be detected by making sure the sensor reading
changes by the same amount as the intrusive change in emissions.
Lastly, the sensor response to decreasing NOX concentrations
could also be evaluated by measuring the response when the intrusive
strategy is turned off and engine-out NOX emissions are
returned to normal levels. By correlating sensor response rates and the
resulting
[[Page 3264]]
emissions impacts, the malfunction criteria could then be determined.
B. Feasibility of the Monitoring Requirements for Gasoline/Spark-
Ignition Engines
1. Fuel System Monitoring
For gasoline vehicles since the 1996 model year and gasoline
engines since the 2005 model year, the under 14,000 pound OBD
requirements have required fuel system monitoring identical to that
being proposed. Over 100 million cars and light trucks have been built
and sold in the U.S. to these fuel system monitoring requirements
including some heavy-duty vehicles that use the exact same gasoline
engines that are used in some over 14,000 pound applications. This
clearly demonstrates the technological feasibility of the proposed
requirements.
2. Engine Misfire Monitoring
For gasoline vehicles since the 1996 model year and gasoline
engines since the 2005 model year, the under 14,000 pound OBD
requirements have required misfire monitoring identical to that being
proposed. One of the most reliable methods for detecting misfire is the
use of a crankshaft position sensor--which measures the fluctuations in
engine angular velocity to determine the presence of misfire--along
with a camshaft position sensor--which can be used to identify the
misfiring cylinder. This method has been shown to be technologically
feasible and should work equally well on over 14,000 pound
applications.
3. Exhaust Gas Recirculation (EGR) Monitoring
For vehicles since the 1996 model year and engines since the 2005
model year, the under 14,000 pound OBD requirements have required EGR
system monitoring identical to that being proposed. The general
approach has been to detect EGR flow rate malfunctions by looking at
the change in fuel trim or manifold pressure under conditions when the
EGR system is active. This demonstrates the technological feasibility
of the proposed requirements.
4. Cold Start Emission Reduction Strategy Monitoring
We expect this monitoring to be done mainly via computer software.
For example, if spark retard is used during cold starts, the commanded
amount of spark retard would have to be monitored if the amount of
spark retard can be restricted by external factors such as idle quality
or driveability. This can be done with software algorithms that compare
the actual overall commanded final ignition timing with the threshold
timing that would result in emissions that exceed the emissions
thresholds. Cold start strategies that always command a predetermined
amount of ignition retard independent of all other factors and do not
allow idle quality or other factors to override the desired ignition
retard would not require monitoring of the commanded timing. Other
methods that could be used to ensure that the actual timing has been
reached include verifying other factors such as corresponding increases
in mass air flow and idle speed indicative of retarded spark
combustion. Both mass air flow and idle speed are used currently by the
engine control system and the OBD system and, therefore, only minor
software modifications should be required to analyze these signals
while the cold start strategy is invoked.
5. Secondary Air System Monitoring
A/F sensors would most likely be required to monitor effectively
the secondary air system when it is normally active. These sensors are
currently installed on many new cars and their implementation is
projected to increase in the future as more stringent emission
standards are phased in. A/F sensors are useful in determining air-fuel
ratio over a broader range than conventional oxygen sensors and are
especially valuable in engines that require very precise fuel control.
They would be useful for secondary air system monitoring because of
their ability to determine air-fuel ratio with high accuracy. This
would enable a correlation between secondary airflow rates and
emissions.
6. Catalytic Converter Monitoring
A common method used for estimating catalyst efficiency is to
measure the catalyst's oxygen storage capacity. This monitoring method
has been used by all light-duty gasoline vehicles since the 1996 model
year and most gasoline engines since the 2005 model year as a result of
our under 14,000 OBD requirements. Generally, as the catalyst's oxygen
storage capacity decreases, the conversion efficiencies of HC and
NOX also decrease. With this strategy, a catalyst
malfunction would be detected when its oxygen storage capacity has
deteriorated to a predetermined level. Manufacturers determine this by
using the information from an upstream oxygen sensor and a downstream
or mid-bed oxygen sensor (this second sensor is also used for trimming
the front sensor to maintain more precise fuel control). By comparing
the level of oxygen measured by the second sensor with that measured by
the upstream sensor, manufacturers can determine the catalyst's oxygen
storage capacity and estimate its conversion efficiency. With a
properly functioning catalyst, the second oxygen sensor signal will be
fairly steady since the fluctuating oxygen concentration (due to fuel
system cycling around stoichiometry) at the inlet of the catalyst is
damped by the storage and release of oxygen in the catalyst. When a
catalyst is deteriorated it is no longer capable of storing and
releasing oxygen. This causes the frequency and peak-to-peak voltage of
the second oxygen sensor to simulate the signal from the upstream
oxygen sensor at which time a malfunction would be indicated.
7. Evaporative System Monitoring
Our OBD requirements have required monitoring for evaporative
system leaks for many years. The EPA OBD requirement has been the
equivalent of a 0.040 inch hole, while the ARB requirement has gone as
low as a 0.020 inch hole. These requirements have been met on
applications such as incomplete trucks and engine dynamometer certified
configurations equipped with similar and, in many cases, identical
configurations as are used in over 14,000 pound applications.
Manufacturers have successfully met these requirements by using engine
vacuum to create a vacuum in both the fuel tank and evaporative system
and then monitoring the system's ability to maintain that vacuum. The
ramp down in vacuum (or ramp up in pressure) can then be correlated to
leak size. In general, these systems require the addition of an
evaporative system pressure sensor and a canister vent valve capable of
closing the vent line.
Manufacturers of over 14,000 pound applications have expressed
concerns with their ability to detect evaporative system leaks on these
larger vehicles. One such concern relates to the relatively larger fuel
tank sizes on the larger applications. These tanks can be on the order
of 50 to 80 gallons, which makes the impact of a small hole, on a
percentage basis, less severe and less easily detected. Another concern
is the relatively large number of fuel tank and evaporative system
configurations on the larger applications. Confounding both of these
concerns is that the engine manufacturers quite often have no idea what
tanks and configurations will ultimately be matched with their engine
in the final vehicle product.
While we agree that these concerns are valid, they can also be said
of the
[[Page 3265]]
under 14,000 pound applications (except perhaps the tank size concern).
The over 14,000 pound gasoline applications are expected to use near
identical, if not equivalent, evaporative system components and we are
not aware of any reason why the existing monitoring techniques would
not continue to work on over 14,000 pound applications. Nonetheless, we
do not want false failures in the field. By limiting the monitoring
requirement to leaks of 0.150 inch or larger, we believe that
manufacturers would be able to employ a single monitoring strategy to
all possible tank sizes and configurations without much concern for
false failures. Nonetheless, it may be necessary for manufacturers to
impose tighter restrictions on their engine purchasers than is done
currently with regards to tank specifications and evaporative system
components.
8. Exhaust Gas Sensor Monitoring
Our light-duty OBD requirements since the 1996 model year and our
8,500 to 14,000 pound OBD requirements since the 2005 model year have
required oxygen sensor monitoring similar to the requirements being
proposed. Years of compliance with those requirements demonstrates the
technological feasibility of the proposed requirements. Additionally,
A/F sensor monitoring has been required and demonstrated on these
vehicles for many years.
C. Feasibility of the Monitoring Requirements for Other Diesel and
Gasoline Systems
1. Variable Valve Timing and/or Control (VVT) System Monitoring
VVT systems are already in general use in many under 14,000 pound
applications. Further, under the California OBD II requirements,
vehicles equipped with VVT systems have been monitoring those systems
for proper function since the 1996 model year. More recently,
manufacturers have employed monitoring strategies to detect VVT system
malfunctions that detect not only proper function but also exceedances
of emissions thresholds. Such strategies include the use of the crank
angle sensor and camshaft position sensor to confirm that the valve
opening and closing occurs within an allowable tolerance of the
commanded crank angle. By calculating the difference between the
commanded valve opening crank angle and the achieved valve opening
crank angle, a diagnostic algorithm can differentiate between a
malfunctioning system with too large of an error and a properly
functioning system with very little to no error. By calibrating the
size of this error (or integrating it over time), manufacturers can
design the system to indicate a malfunction prior to the required
emissions thresholds. In the same manner, system response can be
measured by monitoring the length of time necessary to achieve the
commanded valve timing. To ensure adequate resolution between properly
functioning systems and malfunctioning systems, most manufacturers
perform this type of monitor only when a sufficiently large ``step
change'' in commanded valve timing occurs.
2. Engine Cooling System Monitoring
The existing OBD requirements have required identical ECT sensor
and thermostat monitoring for several years. While the technical
feasibility of the proposed requirements has been demonstrated on
lighter applications which tend to be produced through a vertically
integrated manufacturing process, the manufacturers of big diesel
engines have expressed concerns that monitoring of the cooling system
on over 14,000 pound applications would create unique and possibly
insurmountable challenges. Generally, the cooling system is divided
into two cooling circuits connected by the thermostat. The two circuits
are the engine circuit and the radiator circuit. Since the big diesel
engine industry tends to be horizontally integrated, the manufacturers
contend that they do not know what types of devices will be added to
the cooling system when the vehicle is manufactured or the vehicle is
put into service. They are concerned that the unknown devices can add/
remove unknown quantities of heat to/from the system which would
prevent them from predicting reliably the proper system behavior (e.g.,
warm up). Without the ability to predict system behavior reliably, they
fear that they cannot know when the system is malfunctioning (e.g., not
warming up as expected).
The industry's concerns regarding unknown devices added on the
radiator circuit of the system seem unwarranted. A properly functioning
thermostat does not allow flow through the radiator during warm-up.
Devices added to the radiator circuit could only affect coolant
temperature when there is significant coolant flow through the radiator
(i.e., after the engine is warmed-up and the thermostat is open,
allowing coolant to flow through the radiator).
We agree that unknown devices added on the engine circuit (e.g.,
passenger compartment heaters) can affect the warm-up rate of the
system. Manufacturers of under 14,000 pound applications have
demonstrated robust thermostat monitoring with high capacity passenger
heaters in the cooling system. To do so, they have to know the maximum
rate of heat loss due to the heater. Manufacturers of over 14,000 pound
applications have control over this by providing limits on such devices
in the build specifications that they provide to the vehicle
manufacturers. In some cases, an engine manufacturer might need
multiple build specifications with corresponding thermostat monitoring
calibrations to accommodate the ranges of heater capacities that are
needed when a given engine is used in a range of vehicle applications
(e.g., a local delivery truck having a passenger compartment for two
people and a small capacity heater versus a bus having a passenger
compartment for 20 people and a large capacity heater). The vehicle
manufacturer would then select the appropriate calibration for the
engine when installing it in the vehicle. Nonetheless, engine
manufacturers have requested limited enable conditions for the
thermostat monitor (e.g., to disable the thermostat monitor below 50
degrees F). This would help to minimize their resource needs to
calibrate the thermostat monitor. While this may be directionally
favorable to manufacturers, it would result in disabled thermostat
monitoring during cold ambient conditions which occur in much of the
country and, in some areas, during a large portion of the year. In such
regions, a vehicle could experience a thermostat malfunction with no
indication to the vehicle operator. Since many other OBD monitors will
operate only after reaching a certain engine coolant temperature, a
malfunctioning thermostat without any indication could effectively
result in disablement of the OBD system.
3. Crankcase Ventilation System Monitoring
Crankcase ventilation system monitoring requirements have been met
for years by manufacturers of under 14,000 pound gasoline applications.
Therefore, the technological feasibility has been demonstrated for
gasoline applications.
Effectively, diesel engine manufacturers would be required to meet
design requirements for the entire system in lieu of actually
monitoring any of the hoses for disconnection. Specifically, the
proposed requirement would allow for an exemption for any portion of
the system that is resistant to deterioration or accidental
disconnection and not subject to disconnection during any of the
[[Page 3266]]
manufacturer's repair procedures for non-crankcase ventilation system
repair work. These safeguards would be expected to eliminate the
chances of disconnected or improperly connected hoses while still
allowing manufacturers to meet the requirements without adding any
additional hardware meant solely for the purpose of meeting the
monitoring requirements.
4. Comprehensive Component Monitoring
Both ARB and EPA OBD requirements have for year contained
requirements to monitor computer input and output components. While
these monitors are sometimes tricky and are not easy as many
incorrectly assume, the many years of successful implementation and
compliance with the existing requirements demonstrates their
feasibility. The proposed requirements are equivalent to the under
14,000 pound requirements.
IV. What Are the Service Information Availability Requirements?
A. What Is the Important Background Information for the Proposed
Service Information Provisions?
Section 202(m)(5) of the CAA directs EPA to promulgate regulations
requiring OEMs to provide to:
any person engaged in the repairing or servicing of motor vehicles
or motor vehicle engines, and the Administrator for use by any such
persons, * * * any and all information needed to make use of the
[vehicle's] emission control diagnostic system * * * and such other
information including instructions for making emission-related
diagnoses and repairs.
Such requirements are subject to the requirements of section 208(c)
regarding protection of trade secrets; however, no such information may
be withheld under section 208(c) if that information is provided
(directly or indirectly) by the manufacturer to its franchised dealers
or other persons engaged in the repair, diagnosing or servicing of
motor vehicles.
On June 27, 2003 EPA published a final rulemaking (68 FR 38428)
which set forth the Agency's service information regulations for light-
and heavy-duty vehicles and engines below 14,000 pounds GVWR. These
regulations, in part, required each-covered Original Equipment
Manufacturer (OEM) to do the following: (1) OEMs must make full text
emissions-related service information available via the World Wide Web.
(2) OEMs must provide equipment and tool companies with information
that allows them to develop pass-through reprogramming tools. (3) OEMs
must make available enhanced diagnostic information to equipment and
tool manufacturers and to make available OEM-specific diagnostic tools
for sale. These requirements were finalized to ensure that aftermarket
service and repair facilities have access to the same emission-related
service information, in the same or similar manner, as that provided by
OEMs to their franchised dealerships.
As EPA moves forward proposing OBD requirements for the heavy-duty
over 14,000 pounds sector, EPA is similarly moving forward with
proposals to require the availability of service information to heavy-
duty aftermarket service providers as required by section 202(m) of the
Clean Air Act.
All of the following proposed provisions regarding the availability
of service information for the heavy-duty industry are based on our
extensive experience and regulatory history with the light-duty service
industry. However, as discussed below, EPA understands that there may
be significant differences between the light-duty service industry and
the heavy-duty service industry. EPA welcomes comment on all of the
proposed provisions and their need and/or applicability to the heavy-
duty service industry.
B. How Do the Below 14,000 Pound and Above 14,000 Pounds Aftermarket
Service Industry Compare?
As we consider proposing the availability of service information
for the heavy-duty sector above 14,000 pounds, EPA recognizes that
differences do exist between the industries that service vehicles above
and below 14,000 pounds. On the below 14,000 pound side, estimates
indicate that independent technicians perform up to 80% of all vehicle
service and repairs once a vehicle exceeds the manufacturer warranty
period.\69\ On the above 14,000 pound side, the 1997 U.S. Census Bureau
Vehicle Inventory and Use Survey, estimated that 25 percent of the
general maintenance and over 30 percent of the major overhaul on heavy-
duty vehicles was performed by the independent sector. According to the
Census Bureau, these values represent a 16.7 percent increase in
general maintenance and a 6.2 percent increase in major overhaul from
1992. Trucks and Parts Service Magazine provides the following
information on the breakdown of the independent repair industry for
vehicles above 14,000 pounds (not including any fuel injection shops):
---------------------------------------------------------------------------
\69\ Motor and Equipment Manufacturers Association, Automotive
Industry Status Report, 1999.
U.S. independent machine shops for above 14,000 pounds--5,820
U.S. independent engine service shops for above 14,000 pounds--12,170
U.S. independent transmission repair shops for above 14,000 pounds--
11,420
Technicians, independent repair shops for above 14,000 pounds--133,700
Technicians, truck parts distributors for vehicles above 14,000
pounds--41,600
Thus, the increase in business and the large number of independent
aftermarket shops make it necessary that repair information is readily
available for the aftermarket trucking industry.
On the light-duty side, vehicle manufacturers are entirely
integrated in that they are responsible for the design and production
of the entire vehicle from the chassis to the body. In comparison, the
heavy-duty industry is mostly non-integrated. In other words, different
manufacturers separately produce the engine, the chassis, and the
transmission of a vehicle. This non-integration speaks to the fact that
a completed vehicle is typically produced in response to the customized
needs of owners/operators. In addition, the lack of integration
indicates that a given engine will ultimately be part of many different
engine, transmission, and chassis configurations. In addition, heavy-
duty manufacturers have stated that diagnostic tool designs differ
significantly from tools produced for light-duty vehicles as a result
of this non-integration.
EPA requests comment and also additional data on the current state
of the heavy-duty aftermarket industry.
C. What Provisions Are Being Proposed for Service Information
Availability?
1. What Information Is Proposed To Be Made Available by OEMs?
Today's action proposes a provision that requires OEMs to make
available to any person engaged in the repairing or servicing of heavy-
duty motor vehicles or motor vehicle engines above 14,000 pounds all
information necessary to make use of the OBD systems and any
information for making emission-related repairs, including any
emissions-related information that is provided by the OEM to franchised
dealers beginning with MY2010. We are proposing that this information
includes, but is not limited to, the following:
(1) Manuals, technical service bulletins (TSBs), diagrams, and
charts (the provisions for training materials,
[[Page 3267]]
including videos and other media are discussed in Sections II.C.3 and
II.C.4 below.
(2) A general description of the operation of each monitor,
including a description of the parameter that is being monitored.
(3) A listing of all typical OBD diagnostic trouble codes
associated with each monitor.
(4) A description of the typical enabling conditions for each
monitor to execute during vehicle operation, including, but not limited
to, minimum and maximum intake air and engine coolant temperature,
vehicle speed range, and time after engine startup. A listing and
description of all existing monitor-specific drive cycle information
for those vehicles that perform misfire, fuel system, and comprehensive
component monitoring.
(5) A listing of each monitor sequence, execution frequency and
typical duration.
(6) A listing of typical malfunction thresholds for each monitor.
(7) For OBD parameters that deviate from the typical parameters,
the OBD description shall indicate the deviation for the vehicles it
applies to and provide a separate listing of the typical values for
those vehicles.
(8) Identification and scaling information necessary to interpret
and understand data available to a generic scan tool through Diagnostic
Message 8 pursuant to SAE Recommended Practice J1939-73, which is
incorporated by reference in section X.
(9) For vehicles below 14,000 pounds, EPA requires that any
information related to the service, repair, installation or replacement
of parts or systems developed by third party (Tier 1) suppliers for
OEMs, to the extent they are made available to franchise dealerships.
EPA believes that Tier 1 suppliers are an important element of the
market related to vehicles below 14,000 pounds and EPA is requesting
comment on the role that Tier 1 suppliers play in the heavy-duty market
above 14,000 pounds and the need to extend this provision to the heavy-
duty industry above 14,000 pounds.
(10) Any information on other systems that can directly effect the
emission system within a multiplexed system (including how information
is sent between emission-related system modules and other modules on a
multiplexed bus),
(11) Any information regarding any system, component, or part of a
vehicle monitored by the OBD system that could in a failure mode cause
the OBD system to illuminate the malfunction indicator light (MIL).
(12) Any other information relevant to the diagnosis and completion
of an emissions-related repair. This information includes, but is not
limited to, information needed to start the vehicle when the vehicle is
equipped with an anti-theft or similar system that disables the engine
described below in paragraph (13). This information also includes any
OEM-specific emissions-related diagnostic trouble codes (DTCs) and any
related service bulletins, trouble shooting guides, and/or repair
procedures associated with these OEM-specific DTCs.
(13) For vehicles below 14,000 pounds, EPA requires that OEMs make
available computer or anti-theft system initialization information
necessary for the proper installation of on-board computers on motor
vehicles that employ integral vehicle security systems or the repair or
replacement of any other emission-related part. We did not finalize a
provision that would require OEMs to make this information available on
the OEM's Web site unless they chose to do so. However, we did finalize
a provision requiring that the OEM's Web site contain information on
alternate means for obtaining the information and/or ability to perform
reintialization. EPA is proposing to expand this provision to OEMs for
vehicles above 14,000 pounds and requests comment on the prevalence of
this type of repair, the means and methods for performing this type of
repair and the need to extend this provision to the heavy-duty
industry.
In addition, EPA's current service information rules require that,
beginning with the 2008 model year, all OEM systems will be designed in
such a way that no special tools or processes will be necessary to
perform re-initialization. In other words, EPA expects that the re-
initialization of vehicles can be completed with generic aftermarket
tools, a pass-through device, or an inexpensive OEM-specific cable. EPA
finalized this provision for vehicles below 14,000 pounds to prevent
the need for aftermarket service providers to invest in expensive OEM-
specific or specialty tools to complete an emissions-related repair
that does not occur very frequently, but does in fact occur. In the
June 2003 final rule, EPA gave OEMs a significant amount of lead time
to either separate the need for reinitialization from an emissions
related repair or otherwise redesign the reinitialization process in
such a way that it does not require the use of special tools. EPA
requests comment on the need for such a provision for the above 14,000
pound market. To the extent that such a provision may be needed for the
heavy-duty arena, EPA also requests comment and what lead-time might be
needed to meet EPA's goal of not relying on special tools or processes
to perform reinitialization.
Information for making emission-related repairs does not include
information used to design and manufacture parts, but may include OEM
changes to internal calibrations, and other indirect information, as
discussed below.
2. What Are the Proposed Requirements for Web-Based Delivery of the
Required Information?
a. OEM Web Sites
Today's action proposes a provision that would require OEMs to make
available in full-text all of the information outlined above, on
individual OEM Web sites. Today's action further proposes that each OEM
launch their individual Web sites with the required information within
6 months of publication of the final rule for all 2010 and later model
year vehicles. The only proposed exceptions to the full-text
requirements are training information, anti-theft information, and
indirect information.
b. Timeliness and Maintenance of Information on OEM Web Sites
Today's action proposes a provision that would require OEMs to make
available the required information on their Web site within six months
of model introduction. After this six month period, we propose that the
required information for each model must be available and updated on
the OEM Web site at the same time it is available by any means to their
dealers.
For vehicles under 14,000 pounds, EPA finalized a provision that
OEMs maintain the required information in full text on their Web sites
for at least 15 years after model introduction. After this fifteen-year
period, OEMs can archive the required service information, but it must
be made available upon request, in a format of the OEM's choice (e.g.
CD-ROM). Given the significantly longer lifetime of heavy-duty vehicles
and engines above 14,000 pounds, EPA requests comment on the need to
require that the required information be required to remain on the Web
sites for a longer period of time.
c. Accessibility, Reporting and Performance Requirements for OEM Web
Sites
Performance reports that adequately demonstrate that their
individual Web sites meets the requirements outlined in Section C(1)
above will be submitted to the Administrator annually or upon
[[Page 3268]]
request by the Administrator. These reports shall also indicate the
performance and effectiveness of the Web sites by using commonly used
Internet statistics (e.g. successful requests, frequency of use, number
of subscriptions purchased, etc). EPA will issue additional direction
in the form of official manufacturer guidance to further specify the
process for submitting reports to the Administrator.
In addition, EPA is proposing a provision that requires OEMs to
launch Web sites that meet the following performance criteria:
(1) OEM Web sites shall possess sufficient server capacity to allow
ready access by all users and have sufficient downloading capacity to
assure that all users may obtain needed information without undue
delay;
(2) Broken Web links shall be corrected or deleted weekly.
(3) Web site navigation does not require a user to return to the
OEM home page or a search engine in order to access a different portion
of the site.
(4) It is also proposed that any manufacturer-specific acronym or
abbreviation shall be defined in a glossary webpage which, at a
minimum, is hyperlinked by each webpage that uses such acronyms and
abbreviations. OEMs may request Administrator approval to use alternate
methods to define such acronyms and abbreviations. The Administrator
shall approve such methods if the motor vehicle manufacturer adequately
demonstrates that the method provides equivalent or better ease-of-use
to the Web site user.
(5) Indicates the minimum hardware and software specifications
required for satisfactory access to the Web site(s).
d. Structure and Cost of OEM Web Sites
In addition to the proposed requirements described above, EPA is
proposing that OEMs establish a three-tiered approach for the access to
their Web-based service information. These three tiers are proposed to
include, but are not limited to short-term, mid-term, and long-term
access to the required information.
(1) Short-Term Access
OEMs shall provide short-term access for a period of 24-72 hours
whereby an aftermarket service provider will be able to access that
OEM's Web site, search for the information they need, and purchase and/
or print it for a set fee.
(2) Mid-Term Access
OEMs shall provide mid-term access for a period of 30 days whereby
an aftermarket service provider will be able to access that OEM's Web
site, search for the information they need, and purchase and/or print
it for a set fee.
(3) Long-Term Access
OEMs shall provide long-term access for a period of 365 days
whereby an aftermarket service provider will be able to access that
OEM's Web site, search for the information they need, and purchase and/
or print it for a set fee.
In addition, for each of the tiers, we propose that OEMs make their
entire site accessible for the respective period of time and price. In
other words, we propose that an OEM may not limit any or all of the
tiers to just one make or one model.
EPA finalized the three-tiered information access approach in our
June 2003 rulemaking to accommodate the wide variety of ways in which
EPA believes aftermarket service providers utilize service information.
On the under 14,000 side, aftermarket technicians approach the service
of vehicles anywhere from servicing any make or model that comes into
their shops to specializing in one particular manufacturer. In
addition, EPA believes that there are other parties such as ``do-it-
yourself'' mechanics or Inspection/Maintenance programs that may be
interested in accessing such OEM web-sites. In addition, aftermarket
service providers for vehicles below 14,000 pounds also relay on third
party information consolidation entities such as Mitchell or All Data
to supplement OEM-specific information. These factors, in addition to
the fact that there are approximately 25ish (check this number) light-
duty vehicle manufacturers, led EPA to the conclusion that a tiered
approach to Web site access was necessary to ensure maximum
availability to the aftermarket. EPA requests comment on the nature of
aftermarket service for the heavy-duty above 14,000 pound industry and
the need for a tiered approach to information availability.
Today's action also proposes that, prior to the official launch of
OEM Web sites, each OEM will be required to present to the
Administrator a specific outline of what will be charged for access to
each of the tiers. We are further proposing that OEMs must justify
these charges, and submit to the Administrator information on the
following parameters, which include but are not limited to, the
following:
(1) The price the manufacturer currently charges their branded
dealers for service information. At a minimum, this must include the
direct price charged that is identified exclusively as being for
service information, not including any payment that is incorporated in
other fees paid by a dealer, such as franchise fees. In addition, we
propose that the OEM must describe the information that is provided to
dealers, including the nature of the information (e.g., the complete
service manual), etc.; whether dealers have the option of purchasing
less than all of the available information, or if purchase of all
information is mandatory; the number of branded dealers who currently
pay for this service information; and whether this information is made
available to any persons at a reduced or no cost, and if so,
identification of these persons and the reason they receive the
information at a reduced cost.
(2) The price the manufacturer currently charges persons other than
branded dealers for service information. The OEM must describe the
information that is provided, including the nature of the information
(e.g., the complete service manual, emissions control service manual),
etc.; and the number of persons other than branded dealers to whom the
information is supplied.
(3) The estimated number of persons to whom the manufacturer would
be expected to provide the service information following implementation
of today's requirements. If the manufacturer is proposing a fee
structure with different access periods (e.g., daily, monthly and
annual periods), the manufacturer must estimate the number of users who
would be expected to subscribe for the different access periods.
A complete list of the proposed criteria for establishing
reasonable cost can be found in the proposed regulatory language for
this final rule. We are also proposing that, subsequent to the launch
of the OEM Web sites, OEMs would be required to notify the
Administrator upon the increase in price of any one or all of the tiers
of twenty percent or more accounting for inflation or that sets the
charge for end-user access over the established price guidelines
discussed above, including a justification based on the criteria for
reasonable cost as established by this regulation.
Throughout the history of the current service information
regulations, the price of service information and how price impacts the
availability of service information has been a source of significant
debate and discussion. In looking at the legislative history that led
to the inclusion of the service information mandate in the Clean Air
Act Amendments of 1990, it is clear that Congress did not intend for
the pricing of information to be an artificial barrier
[[Page 3269]]
to access. Further, Congress did not intend for information access
charges to become a profit center for OEMs. However, EPA has
interpreted that Congress did intend for OEMs to be able to recover
reasonable costs for making information available. Since the initial
implementation of the service information requirements beginning with
original 1995 final rulemaking, EPA has continued to refine the
provisions regulating the cost of service to try to balance the
Congressional intent while understanding that OEMs should be able to
recover reasonable costs for making the required information available
to the aftermarket. In fact, the relatively prescriptive nature of some
of the requirements stem directly from instances on the light-duty side
where, in the past, we believe some manufacturers deliberately priced
access to information in such a way that effectively made it
unavailable to the aftermarket. The provisions being proposed today
regarding the pricing of service information reflect many years of
implementation experience, debate, and discussion on the light-duty
side and EPA specifically requests comment from heavy-duty aftermarket
service providers on current state of pricing of OEM heavy-duty service
information and what else EPA should consider for heavy-duty that might
be different from light-duty.
e. Hyperlinking to and From OEM Web Sites
Today's action proposes a provision that requires OEMs to allow
direct simple hyperlinking to their Web sites from government Web sites
and from all automotive-related Web sites, such as aftermarket service
providers, educational institutions, and automotive associations.
f. Administrator Access to OEM Web Sites
Today's action proposes a provision that requires that the
Administrator shall have access to each OEM Web site at no charge to
the Agency. The Administrator shall have access to the site, reports,
records and other information as provided by sections 114 and 208 of
the Clean Air Act and other provisions of law.
g. Other Media
We are proposing a provision which would require OEMs to make
available for ordering the required information in some format approved
by the Administrator directly from their Web site after the proposed
full-text window of 15 years has expired. It is proposed that each OEM
shall index their available information with a title that adequately
describes the contents of the document to which it refers. In the
alternate, OEMs may allow for the ordering of information directly from
their Web site, or from a Web site hyperlinked to the OEM Web site. We
also propose that OEMs be required to list a phone number and address
where aftermarket service providers can call or write to obtain the
desired information. We also propose that OEMs must also provide the
price of each item listed, as well as the price of items ordered on a
subscription basis. To the extent that any additional information is
added or changed for these model years, OEMs shall update the index as
appropriate. OEMs will be responsible for ensuring that their
information distributors do so within one regular business day of
received the order. Items are less than 20 pages (e.g. technical
service bulletins) shall be faxed to the requestor and distributors are
required to deliver the information overnight if requested and paid for
by the ordering party.
h. Small Volume Provisions for OEM Web Sites
In the July 2003 final rulemaking, EPA finalized a provision to
provide flexibility for small volume OEMs. In particular, EPA finalized
a provision that requires OEMs who are issued certificates of
conformity with total annual sales of less than one thousand vehicles
are be exempt from the full-text Internet requirements, provided they
present to the Administrator and obtain approval for an alternative
method by which emissions-related information can be obtained by the
aftermarket or other interested parties. EPA also finalized a provision
giving OEMs with total annual sales of less than five thousand vehicles
an additional 12 months to launch their full-text Web sites.
These small-volume flexibilities are limited to the distribution
and availability of service information via the World Wide Web under
paragraph (4) of the regulations. All OEMs, regardless of volume, must
comply with all other provisions as finalized in this rulemaking. EPA
is requesting comment on the existence of small volume OEMs in the
heavy-duty arena and the need for any provisions relating to small
volume OEMs.
3. What Provisions Are Being Proposed for Service Information for Third
Party Information Providers?
The nature of the light-duty aftermarket service industry is such
that they rely to a great extent on consolidated service information
that is development by third party information providers such as
Mitchell and All-data. Third-party information providers will license
OEM service information and consolidate that information for sale to
the aftermarket. In the June 2003 final rule, EPA finalized a provision
that will require OEMs who currently have, or in the future engage in,
licensing or business arrangements with third party information
providers, as defined in the regulations, to provide information to
those parties in an electronic format in English that utilizes non-
proprietary software. Further, EPA required that any OEM licensing or
business arrangements with third party information providers are
subject to fair and reasonable cost requirements. Lastly, we expect
that OEMs will develop pricing structures for access to this
information that make it affordable to any third party information
providers with which they do business. EPA proposes to extend these
provisions to the heavy-duty vehicle and engine manufacturers beginning
with the 2010 model year.
However, EPA is specifically requesting comment on what role third-
party consolidated information plays in the heavy-duty aftermarket.
Further, EPA requests comment on the need for these, or additional
provisions, related to third-party information providers.
4. What Requirements are Being Proposed for the Availability of
Training Information?
a. Purchase of Training Materials for OEM Web Sites
In the light-duty service information final rule, EPA finalized two
provisions for access to OEM emissions-related training. First, OEMs
are required to make available for purchase on their Web sites the
following items: Training manuals, training videos, and interactive,
multimedia CD's or similar training tools available to franchised
dealerships. Second, we finalized a provision that OEMs who transmit
emissions-related training via satellite or the Internet must tape
these transmissions and make them available for purchase on their Web
sites within 30 days after the first transmission to franchised
dealerships. Further, all of the items included in this provision must
be shipped within 24 hours of the order being placed and are to be made
available at a reasonable price. We also finalized a provision that
will allow for an exception to the 24 hour shipping requirement in
those circumstances where orders exceed supply and additional time is
needed by the distributor to reproduce the item being ordered. For
subsequent model years,
[[Page 3270]]
the required information must be made available for purchase within
three months of model introduction, and then be made available at the
same time it is made available to franchised dealerships.
EPA is proposing to extend these provisions to the heavy-duty
industry and requests comment on the need to so or to develop other
provisions pertaining to the availability of training information for
the heavy-duty aftermarket.
b. Third Party Access to OEM Training Material
In the light-duty final rule, we also finalized a provision that
requires OEMs who utilize Internet and satellite transmissions to
present emissions-related training to their dealerships to make these
same transmissions available to third party training providers. In this
way, we believe we are providing at least one opportunity for
aftermarket technicians to receive similar emissions-related training
information as provided to dealerships, thus furthering the goals and
letter of section 202(m)(5). This requirement only requires OEMs to
provide the same information to legitimate aftermarket training
providers as is provided to dealerships and aftermarket service
providers. It is not a requirement to license OEM copyrighted materials
to these entities.
OEMs may take reasonable steps to protect their copyright to the
extent some or all of this material may be copyrighted and may refuse
to do business with any party that does not agree to such steps.
However, we do expect OEMs to use fair business practices in its
dealings with these third parties, in keeping with the ``fair and
reasonable price'' requirements in these regulations. OEMs may not
charge unreasonable up-front fees for access to these transmissions,
but OEMs may require a royalty, percentage or other arranged fee based
limits of on a per-use or enrollment subscription basis.
EPA requests comment on the need to expand the light-duty
requirements to the heavy-duty sector. EPA also requests comments on
any additional provisions it should consider to ensure that heavy-duty
aftermarket service providers and trainers have sufficient access to
OEM training information at a fair and reasonable price. EPA also
requests comments on the types of training that is currently
development by heavy-duty OEMs and what processes may already be in
place for availability to the aftermarket.
5. What Requirements Are Being Proposed for Reprogramming of Vehicles?
The 2003 final rule required that light-duty OEMs comply with SAE
J2534, ``Recommended Practice for Pass-Thru Vehicle Programming''. EPA
understands that the heavy-duty industry has a similar standard in
place that is similar to SAE J2534 specification for reprogramming.
Therefore, today's action proposes two options for pass-thru
reprogramming. We are proposing that heavy-duty OEMs comply with SAE
J2534 beginning with 2010 model year. In the alternate, heavy-duty OEMs
may comply with the Technology and Maintenance Council's Recommended
Practice RP1210a, ``Windows Communication API,'' July 1999 beginning in
the 2010 model year. We will also propose a provision that will require
that reprogramming information be made available within 3 months of
vehicle introduction for new models.
6. What Requirements are Being Proposed for the Availability of
Enhanced Information for Scan Tools for Equipment and Tool Companies?
a. Description of Information That Must Be Provided
Today's action proposes a provision that requires OEMs to make
available to equipment and tool companies all generic and enhanced
information, including bi-directional control and data stream
information. In addition, it is proposed that OEMs must make available
the following information.
(i) The physical hardware requirements for data communication (e.g.
system voltage requirements, cable terminals/pins, connections such as
RS232 or USB, wires, etc.).
(ii) ECU data communication (e.g. serial data protocols,
transmission speed or baud rate, bit timing requirements, etc.).
(iii) Information on the application physical interface (API) or
layers. (i.e., processing algorithms or software design descriptions
for procedures such as connection, initialization, and termination).
(iv) Vehicle application information or any other related service
information such as special pins and voltages or additional vehicle
connectors that require enablement and specifications for the
enablement.
(v) Information that describes which interfaces, or combinations of
interfaces, from each of the categories as described in paragraphs
(g)(12)(vii)(A) through (D) of the regulatory language.
b. Distribution of Enhanced Diagnostic Information
Today's action proposes a provision that will require the above
information for generic and enhanced diagnostic information be provided
to aftermarket tool and equipment companies with whom appropriate
licensing, contractual, and confidentiality agreements have been
arranged. This information shall be made available in electronic format
using common document formats such as Microsoft Excel, Adobe Acrobat,
Microsoft Word, etc. Further, any OEM licensing or business
arrangements with equipment and tool companies are subject to a fair
and reasonable cost determination.
7. What Requirements Are Being Proposed for the Availability of
OEM-Specific Diagnostic Scan Tools and Other Special Tools?
a. Availability of OEM-Specific Diagnostic Scan Tools
Today's action proposes a provision that OEMs must make available
for sale to interested parties the same OEM-specific scan tools that
are available to franchised dealerships, except as discussed below. It
is proposed that these tools shall be made available at a fair and
reasonable price. It is also proposed, that these tools shall also be
made available in a timely fashion either through the OEM Web site or
through an OEM-designated intermediary.
b. Decontenting of OEM-Specific Diagnostic Scan Tools
Today's action proposes a provision that requires OEMs who opt to
remove non-emissions related content from their OEM-specific scan tools
and sell them to the persons specified in paragraph (g)(2)(i) and
(f)(2)(i) of the regulatory language for this final rule shall adjust
the cost of the tool accordingly lower to reflect the decreased value
of the scan tool. It is proposed that all emissions-related content
that remains in the OEM-specific tool shall be identical to the
information that is contained in the complete version of the OEM-
specific tool. Any OEM who wishes to implement this option must request
approval from the Administrator prior to the introduction of the tool
into commerce.
c. Availability of Special Tools
The 2003 final rule precluded light-duty OEMs from using special
tools to extinguish the malfunction indicator light (MIL) beginning
with model year 2004. For model years 1994 through 2003, the final rule
required OEMs who
[[Page 3271]]
currently require such tools to extinguish the MIL must release the
necessary information to equipment and tool companies to design a
comparable generic tool. We also required that this information shall
be made available no later than one month following the effective date
of the Final Rule. EPA requests comment on this or other special tools
that may be unique to the heavy-duty industry and on the need for
provisions covering these tools.
8. Which Reference Materials are Being Proposed for Incorporation by
Reference?
Today's action will finalize a provision requiring that OEMs comply
with the following SAE Recommended Practices.
(1) SAE Recommended Practice J2403 (October 1998), ``Medium/Heavy-
Duty EE Systems Diagnosis Nomenclature'' beginning with the 2010 model
year.
(2) SAE Recommended Practice J2534 (February, 2002), ``Recommended
Practice for Pass-Thru Vehicle Reprogramming''. EPA will require that
OEMs comply with SAE J2534 beginning with the 2010 model year.
(3) SAE Recommended Practice J1939-73.
(4) ISO/DIS 15031-5 April 30, 2002.
V. What Are the Emissions Reductions Associated With the Proposed OBD
Requirements?
In the 2007HD highway rule, we estimated the emissions reductions
we expected to occur as a result of the emissions standards being made
final in the rule. Since the OBD requirements contained in today's
proposal are considered by EPA to be an important element of the 2007HD
highway program and its ultimate success, rather than a new element
being included as an addition to that program, we are not estimating
emissions reductions associated with today's proposal. Instead, we
consider the new 2007/2010 tailpipe emissions standards and fuel
standards to be the drivers of emissions reductions and HDOBD to be
part of the assurance we all have that those emissions reductions are
indeed realized. Therefore, this analysis presents the emissions
reductions estimated for the 2007HD highway program. Inherent in those
estimates is an understanding that, while emissions control systems
sometimes malfunction, they presumably are repaired in a timely manner.
Today's proposed OBD requirements would provide substantial tools to
assure that our presumption will be realized by helping to ensure that
emission control systems continue to operate properly throughout their
life. We believe that the OBD requirements proposed today would lead to
more repairs of malfunctioning or deteriorating emission control
systems, and may also lead to emission control systems that are more
robust throughout the life of the engine and less likely to trigger
illumination of MILs. The requirements would therefore provide greater
assurance that the emission reductions expected from the Clean Diesel
Trucks and Buses program will actually occur. Viewed from another
perspective, while the OBD requirements would not increase the emission
reductions that we estimated for the 2007HD highway rule, they would be
expected to lead to actual emission reductions in-use compared with a
program with no OBD system.
The costs associated with HDOBD were not fully estimated in the
2007HD highway rule. Those costs are more fully considered in section
VI of this preamble. These newly developed HDOBD costs are added to
those costs estimated for the 2007/2010 standards and a new set of
costs for those standards are presented in section VII. Section VII
also calculates a new set of costs per ton associated with the 2007/
2010 standards which include the previously estimated costs and
emissions reductions for the 2007/2010 standards and the newly
estimated costs associated with today's HDOBD proposal.
Here we present the emission benefits we anticipate from heavy-duty
vehicles as a result of our 2007/2010 NOX, PM, and NMHC
emission standards for heavy-duty engines. The graphs and tables that
follow illustrate the Agency's projection of future emissions from
heavy-duty vehicles for each pollutant. The baseline case represents
future emissions from heavy-duty vehicles at present standards
(including the MY2004 standards). The controlled case represents the
future emissions from heavy-duty vehicles once the new 2007/2010
standards are implemented. A detailed analysis of the emissions
reductions associated with the 2007/2010 HD highway standards is
contained in the Regulatory Impact Analysis for that final rule.\70\
The results of that analysis are presented in Table V.A-1 and in
Figures V.A-1 through V.A-3.
---------------------------------------------------------------------------
\70\ Regulatory Impact Analysis: Heavy-Duty Engine and Vehicle
Standards and Highway Diesel Fuel Sulfur Control Requirements;
EPA420-R-00-026; December 2000.
Table V.A-1.--Annual Emissions Reductions Associated With the 2007HD
Highway Program
[thousand short tons]
------------------------------------------------------------------------
Year NOX PM NMHC
------------------------------------------------------------------------
2007......................................... 58 11 2
2010......................................... 419 36 21
2015......................................... 1,260 61 54
2020......................................... 1,820 82 83
2030......................................... 2,570 109 115
------------------------------------------------------------------------
[[Page 3272]]
[GRAPHIC] [TIFF OMITTED] TP24JA07.001
[GRAPHIC] [TIFF OMITTED] TP24JA07.002
[[Page 3273]]
[GRAPHIC] [TIFF OMITTED] TP24JA07.003
BILLING CODE 6560-50-C
There were additional estimated emissions reductions associated
with the 2007HD highway rule--namely CO, SOX, and air
toxics. We have not presented those additional emissions reductions
here since, while HDOBD will identify malfunctions and hasten their
repair with the result of reducing all emissions constituents, these
additional emissions are not those specifically targeted by OBD
systems.
VI. What Are the Costs Associated With the Proposed OBD Requirements?
Estimated engine costs are broken into variable costs and fixed
costs. Variable costs are those costs associated with any new hardware
required to meet the proposed requirements, the associated assembly
time to install that hardware, and the increased warranty costs
associated with the new hardware. Variable costs are additionally
marked up to account for both manufacturer and dealer overhead and
carrying costs. The manufacturer's carrying cost was estimated to be
four percent of the direct costs to account for the capital cost of the
extra inventory and the incremental costs of insurance, handling, and
storage. The dealer's carrying cost was estimated to be three percent
of their direct costs to account for the cost of capital tied up in
inventory. We adopted this same approach to markups in the 2007HD
highway rule and our more recent Nonroad Tier 4 rule based on industry
input.
Fixed costs considered here are those for research and development
(R&D), certification, and production evaluation testing. The fixed
costs for engine R&D are estimated to be incurred over the four-year
period preceding introduction of the engine. The fixed costs for
certification include costs associated with demonstration testing of
OBD parent engines including the ``limit'' parts used to demonstrate
detection of malfunctions at or near the applicable OBD thresholds, and
generation of certification documentation. Production evaluation
testing includes testing real world products for standardization
features, monitor function, and performance ratios. The certification
costs are estimated to be incurred one year preceding introduction of
the engine while the production evaluation testing is estimated to
occur in the same year as introduction.
The details of our cost analysis are contained in the technical
support document which can be found in the docket for this rule.\71\ We
have only summarized the results of that analysis here and point the
reader to the technical support document for details. We request
comment on all aspects of our cost analysis.
---------------------------------------------------------------------------
\71\ Draft Technical Support Document, HDOBD NPRM, EPA420-D-06-
006, Docket ID EPA-HQ-OAR-2005-0047-0008.
---------------------------------------------------------------------------
A. Variable Costs for Engines Used in Vehicles Over 14,000 Pounds
The variable costs we have estimated represent those costs
associated with various sensors that we believe would have to be added
to the engine to provide the required OBD monitoring capability. For
the 2010 model year, we believe that upgraded computers and the new
sensors needed for OBD would result in costs to the buyer of $40 and
$50 for diesel and gasoline engines, respectively. For the 2013 model
year, we have included costs associated with the dedicated MIL and its
wiring resulting in a hardware cost to the buyer of $50 and $60 for
both diesel and gasoline engines, respectively. By multiplying these
costs per engine by the projected annual sales we get annual costs of
around $40-50 million for diesel engines and $3-4 million for gasoline
engines, depending on sales. The 30 year net present value of the
annual variable costs would be $666 million and $352 million at a three
percent and a seven percent discount rate, respectively. These costs
are summarized in Table VI.A-1.
[[Page 3274]]
Table VI.A-1.--OBD Variable Costs for Engines Used in Vehicles Over
14,000 Pounds
[All costs in $millions except per engine costs; 2004 dollars]
------------------------------------------------------------------------
Diesel Gasoline Total
------------------------------------------------------------------------
Cost per engine (2010-2012)...... $40 $50 n/a
Cost per engine (2013+).......... 50 60 n/a
Annual Variable Costs in 2010 \a\ 14 1 $15
Annual Variable Costs in 2013 \a\ 38 3 40
Annual Variable Costs in 2030 \a\ 48 4 52
30 year NPV at a 3% discount rate 620 47 666
30 year NPV at a 7% discount rate 328 25 352
------------------------------------------------------------------------
\a\ Annual variable costs increase as projected sales increase.
B. Fixed Costs for Engines Used in Vehicles Over 14,000 Pounds
We have estimated fixed costs for research and development (R&D),
certification, and production evaluation testing. The R&D costs include
the costs to develop the computer algorithms required to diagnose
engine and emission control systems, and the costs for applying the
developed algorithms to each engine family and to each variant within
each engine family. R&D costs also include the testing time and effort
needed to develop and apply the OBD algorithms. The certification costs
include the costs associated with testing of durability engines (i.e.,
the OBD parent engines), the costs associated with generating the
``limit'' parts that are required to demonstrate OBD detection at or
near the applicable emissions thresholds, and the costs associated with
generating the necessary certification documentation. Production
evaluation testing costs included the costs associated with the three
types of production testing: standardization features, monitor
function, and performance ratios.
Table VI.B-1 summarizes the R&D, certification, and production
evaluation testing costs that we have estimated. The R&D costs we have
estimated were totaled and then spread over the four year period prior
to implementation of the requirements for which the R&D is conducted.
By 2013, all of the R&D work would be completed in advance of 100
percent compliance in 2013; hence, R&D costs are zero by 2013.
Certification costs are higher in 2013 than in 2010 because 2010
requires one engine family to comply while 2013 requires all engine
families to comply. The 30 year net present value of the annual fixed
costs would be $291 million and $241 million at a three percent and a
seven percent discount rate, respectively.
Table VI.B-1.--OBD Fixed Costs for Engines Used in Vehicles Over 14,000 Pounds
[All costs in $millions; 2004 dollars]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Diesel Gasoline
--------------------------------------------------------------------------------------------------
Certification Certification
R&D & PE testing Subtotal R&D & PE testing Subtotal Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual OBD Fixed Costs in given years:
2010............................................. $51 $0.2 $52 $0.9 <$0.1 $1 $53
2013............................................. 0 0.4 0.4 0 <0.1 <0.1 0.4
2030............................................. 0 3 3 0 <0.1 <0.1 3
30 year NPV at the given discount rate:
3 percent........................................ $263 $17 $280 $10 $0.3 $10 $291
7 percent........................................ 223 10 232 9 0.2 9 241
--------------------------------------------------------------------------------------------------------------------------------------------------------
C. Total Costs for Engines Used in Vehicles Over 14,000 Pounds
The total OBD costs for engines used in vehicles over 14,000 pounds
are summarized in Table VI.C-1. As shown in the table, the 30 year net
present value cost is estimated at $1 billion and $594 million at a
three percent and a seven percent discount rate, respectively. These
costs are much lower than the 30 year net present value costs estimated
for the 2007HD highway emissions standards which were $25 billion and
$15 billion at a three percent and a seven percent discount rate,
respectively, for diesel and gasoline engines. Including the cost for
the diesel fuel changes resulted in 30 year net present value costs for
that rule of $70 billion and $42 billion at a three percent and a seven
percent discount rate, respectively. See section VII for more details
regarding the cost estimates from the 2007HD highway final rule.
[[Page 3275]]
Table VI.C-1.--OBD Total Costs for Engines Used in Vehicles Over 14,000
Pounds
[All costs in $millions; 2004 dollars]
------------------------------------------------------------------------
Diesel Gasoline Total
------------------------------------------------------------------------
Annual OBD Total Costs in given years
------------------------------------------------------------------------
2010................................... $65 $2 $67
2013................................... 38 3 41
2030................................... 51 4 55
------------------------------------------------------------------------
30 year NPV at the given discount rate
------------------------------------------------------------------------
3%..................................... 900 57 957
7%..................................... 560 34 594
------------------------------------------------------------------------
D. Costs for Diesel Heavy-Duty Vehicles and Engines Used in Heavy-duty
Vehicles Under 14,000 Pounds
The total OBD costs for 8,500 to 14,000 pound diesel applications
are summarized in Table VI.D-1. As shown in the table, the 30 year net
present value cost is estimated at $6 million and $5 million at a three
percent and a seven percent discount rate, respectively. These costs
represent the incremental costs of the proposed additional OBD
requirements, as compared to our current OBD requirements, for 8,500 to
14,000 pound diesel applications and do not represent the total costs
for 8,500 to 14,000 pound diesel OBD. We are proposing no changes to
the 8,500 to 14,000 pound gasoline requirements so, therefore, have
estimated no costs for gasoline vehicles. Details behind these
estimated costs can be found in the technical support document
contained in the docket for this rule.\72\
---------------------------------------------------------------------------
\72\ Draft Technical Support Document, HDOBD NPRM, EPA420-D-06-
006, Docket ID EPA-HQ-OAR-2005-0047-0008.
Table VI.D-1.--Total OBD Costs for 8,500 to 14,000 Pound Diesel
Applications
[All costs in $millions; 2004 dollars]
------------------------------------------------------------------------
Diesel Gasoline Total
------------------------------------------------------------------------
Annual OBD Total Costs in given years
------------------------------------------------------------------------
2010................................... $0.1 $0 $0.1
2013................................... 0 0 0
2030................................... 0.4 0 0.4
------------------------------------------------------------------------
30 year NPV at the given discount rate
------------------------------------------------------------------------
3%..................................... 6 0 6
7%..................................... 5 0 5
------------------------------------------------------------------------
VII. What are the Updated Annual Costs and Costs per Ton Associated
With the 2007/2010 Heavy-duty Highway Program?
In the 2007HD highway rule, we estimated the costs we expected to
occur as a result of the emissions standards being made final in that
rule. As noted in section V, we consider the OBD requirements contained
in today's proposal to be an important element of the 2007HD highway
program and its ultimate success and not a new element being included
as an addition to that program. In fact, without the proposed OBD
requirements we would not expect the emissions reductions associated
with the 2007/2010 standards to be fully realized because emissions
control systems cannot be expected to operate without some need for
repair which, absent OBD, may well never be done. However, as noted in
section VI, because we did not include an OBD program in the 2007HD
highway program, we did not estimate OBD related costs at that time. We
have now done so and those costs are presented in section VI.
Here we present the OBD costs as part of the greater 2007HD highway
program. To do this, we present both the costs developed for that
program and the additional OBD costs presented in section VI. We also
calculate a new set of costs per ton associated with the 2007/2010
standards which include the previously estimated costs and emissions
reductions for the 2007/2010 standards and the newly estimated costs
associated with today's HDOBD proposal.
Note that the costs estimates associated with the 2007HD highway
program were done using 1999 dollars. We have estimated OBD costs in
2004 dollars. We consulted the Producer Price Index (PPI) for ``Motor
vehicle parts manufacturing-new exhaust system parts'' developed by the
Bureau of Labor Statistics and found that the PPI for such parts had
actually decreased from 1999 to 2004.\73\ This suggests that the cost
to produce exhaust system parts has decreased since 1999. For clarity,
rather than adjusting downward the 2007HD highway program costs from
1999 dollars, or adjusting upward the OBD costs from 2004 dollars, we
have chosen to present the 2007HD highway rule costs as they were
presented in that final rule alongside the OBD costs presented in
section VI. In short, we are ignoring the PPI effect in the following
tables.
---------------------------------------------------------------------------
\73\ See www.bls.gov/ppi; All other motor vehicle parts mfg;
Exhaust system parts, new; series ID PCU3363993363993; Base date
8812.
---------------------------------------------------------------------------
A. Updated 2007 Heavy-Duty Highway Rule Costs Including OBD
Table VII.A-1 shows the 2007HD highway program costs along with the
estimated OBD related costs.
Table VII.A-1.--Updated 2007HD Highway Program Costs, Including New OBD-Related Costs, Net Present Value of
Annual Costs for the Years 2006-2035
[All costs in $millions]
----------------------------------------------------------------------------------------------------------------
2007 HD Highway Final Rule
---------------------------------------------------- Updated
Gasoline Proposed HD total
Discount rate Diesel engine & Diesel fuel Original OBD program
engine vehicle costs total costs costs
costs costs
----------------------------------------------------------------------------------------------------------------
3 percent......................... $23,721 $1,514 $45,191 $70,427 $963 $71,389
7 percent......................... 14,369 877 26,957 42,203 599 42,802
----------------------------------------------------------------------------------------------------------------
[[Page 3276]]
B. Updated 2007 Heavy-Duty Highway Rule Costs per Ton Including OBD
Table VII.B-1 shows the 2007HD highway program costs per ton of
pollutant reduced. These numbers are straight from the 2007HD highway
final rule which contains the details regarding the split between
NOX+NMHC and PM related costs.
Table VII.B-1.--Original 2007HD Highway Program Costs, Emissions Reductions, and $/Ton Reduced
[Net present values are for annual costs for the years 2006-2035]
----------------------------------------------------------------------------------------------------------------
30 year NPV 30 year NPV
Discount rate Pollutant cost reduction $/ton
($billions) (million tons)
----------------------------------------------------------------------------------------------------------------
3 percent............................. NOX+NMHC................ 54.6 30.6 1,780
PM...................... 16.0 1.4 11,790
7 percent............................. NOX+NMHC................ 34.9 16.2 2,150
PM...................... 10.3 0.8 13,610
----------------------------------------------------------------------------------------------------------------
Table VII.B-2 shows the updated 2007HD highway program costs per
ton of pollutant reduced once the new OBD costs have been included. For
the split between NOX+NMHC and PM-related OBD costs, we have
used a 50/50 allocation. As shown in Table VII.B-2, the OBD costs
associated with the proposed OBD requirements have little impact on the
overall costs and costs per ton of emissions reduced within the context
of the 2007HD highway program.
Table VII.B-2.--Updated 2007HD Highway Program Costs, Emissions Reductions, and $/ton Reduced Including OBD
Related Costs
[Net present values are for annual costs for the years 2006-2035]
----------------------------------------------------------------------------------------------------------------
30 year NPV 30 year NPV
Discount rate Pollutant cost reduction $/ton
($billions) (million tons)
----------------------------------------------------------------------------------------------------------------
3 percent............................. NOX+NMHC................ 55.1 30.6 1,800
PM...................... 16.5 1.4 12,210
7 percent............................. NOX+NMHC................ 35.2 16.2 2,170
PM...................... 10.6 0.8 14,130
----------------------------------------------------------------------------------------------------------------
VIII. What Are the Requirements for Engine Manufacturers?
A. Documentation Requirements
The OBD system certification requirements would require
manufacturers to submit OBD system documentation that represents each
engine family. The certification documentation would be required to
contain all of the information needed to determine if the OBD system
meets the proposed OBD requirements. The proposed regulation lists the
information that would be required as part of the certification
package. If any of the information in the certification package is the
same for all of a manufacturer's engine families (e.g., the OBD system
general description), the manufacturer would only be required to submit
one set of documents each model year for such items that would cover
all of its engine families.
While the majority of the proposed OBD requirements would apply to
the engine and be incorporated by design into the engine control module
by the engine manufacturer, a portion of the proposed OBD requirements
would apply to the vehicle and not be self-contained within the engine.
Examples include the proposed requirements to have a MIL in the
instrument cluster and a diagnostic connector in the cab compartment.
As is currently done by the engine manufacturers, a build specification
is provided to vehicle manufacturers detailing mechanical and
electrical specifications that must be adhered to for proper
installation and use of the engine (and to maintain compliance with
emissions standards). We expect engine manufacturers would continue to
follow this practice so that the vehicle manufacturer would be able to
maintain compliance with the proposed OBD regulations. Installation
specifications would be expected to include instructions regarding the
location, color, and display icon of the MIL (as well as electrical
connections to ensure proper illumination), location and type of
diagnostic connector, and electronic VIN access. During the
certification process, in addition to submitting the details of all of
the diagnostic strategies and other information required, engine
manufacturers would be required to submit a copy of the OBD-relevant
installation specifications provided to vehicle manufacturers and a
description of the method used by the engine manufacturer to ensure
vehicle manufacturers adhere to the provided installation
specifications (e.g., required audit procedures or signed agreements to
adhere to the requirements). We are requiring that this information be
submitted to us to provide a reasonable level of verification that the
proposed OBD requirements would indeed be satisfied. In summary, engine
manufacturers would be responsible for submitting a certification
package that includes:
A detailed description of all OBD monitors, including
monitors on signals or messages coming from other modules upon which
the engine control unit relies to perform other OBD monitors; and,
A copy of the OBD-relevant installation specifications
provided to vehicle manufacturers/chassis builders and the method used
to reasonably ensure compliance with those specifications.
As was discussed in the context of our implementation schedule (see
section II.G.1), the proposed regulations would allow engine
manufacturers to establish
[[Page 3277]]
OBD groups consisting of more than one engine family with each having
similar OBD systems. The manufacturer could then submit only one set of
representative OBD information from each OBD group. We anticipate that
the representative information would normally consist of an application
from a single representative engine rating within each OBD group. In
selecting the engine ratings to represent each OBD group, consideration
should be given to the exhaust emission control components for all
engine families and ratings within an OBD group. For example, if one
engine family within an OBD group has additional emission control
devices relative to another family in the group (e.g., the first family
has a DPF+SCR while the second has only a DPF), the representative
rating should probably come from the first engine family. Manufacturers
seeking to consolidate several engine families into one OBD group would
be required to get approval of the grouping prior to submitting the
information for certification.
Two of the most important parts of the certification package would
be the OBD system description and summary table. The OBD system
description would include a complete written description for each
monitoring strategy outlining every step in the decision-making process
of the monitor, including a general explanation of the monitoring
conditions and malfunction criteria. This description should include
graphs, diagrams, and/or other data that would help our compliance
staff understand how each monitor works and interacts. The OBD summary
table would include specific parameter values. This table would provide
a summary of the OBD system specifications, including: the component/
system, the DTC identifying each related malfunction, the monitoring
strategy, the parameter used to detect a malfunction and the
malfunction criteria limits against which the parameter is evaluated,
any secondary parameter values and the operating conditions needed to
run the monitor, the time required to execute and complete a monitoring
event for both a pass decision and a fail decision, and the criteria or
procedure for illuminating the MIL. In these tables, manufacturers
would be required to use a common set of engineering units to simplify
and expedite the review process.
We are also proposing that the manufacturer submit a logic
flowchart for each monitor that would illustrate the step-by-step
decision process for determining malfunctions. Additionally, we would
need any data that supports the criteria used to determine malfunctions
that cause emissions to exceed the specified malfunction thresholds
(see Tables II.B-1 and II.C-1). The manufacturer would have to include
data that demonstrates the probability of misfire detection by the
misfire monitor over the full engine speed and load operating range
(for gasoline engines only) or the capability of the misfire monitor to
correctly identify a ``one cylinder out'' misfire for each cylinder
(for diesel engines only), a description of all the parameters and
conditions necessary to begin closed-loop fuel control operation (for
gasoline engines only), closed-loop EGR control (for diesel engines
only), closed-loop fuel pressure control (for diesel engines only), and
closed-loop boost control (for diesel engines only). We would also need
a listing of all electronic powertrain input and output signals
(including those not monitored by the OBD system) that identifies which
signals are monitored by the OBD system, and the emission data from the
OBD demonstration testing (as described below). Lastly, the
manufacturer would be expected to provide any other OBD-related
information necessary to determine the OBD compliance status of the
manufacturer's product line.
B. Catalyst Aging Procedures
For purposes of determining the catalyst malfunction criteria for
diesel NMHC converting catalysts, SCR catalysts, and lean
NOX catalysts, and for gasoline catalysts, where those
catalysts are monitored individually, the manufacturer must use a
catalyst deteriorated to the malfunction criteria using methods
established by the manufacturer to represent real world catalyst
deterioration under normal and malfunctioning engine operating
conditions. For purposes of determining the catalyst malfunction
criteria for diesel NMHC converting catalysts, SCR catalysts, and lean
NOX catalysts, and for gasoline catalysts, where those
catalysts are monitored in combination with other catalysts, the
manufacturer would have to submit their catalyst system aging and
monitoring plan to the Administrator as part of their certification
documentation package. The plan would include the description, emission
control purpose, and location of each component, the monitoring
strategy for each component and/or combination of components, and the
method for determining the applicable malfunction criteria including
the deterioration/aging process.
C. Demonstration Testing
While the proposed certification documentation requirements
discussed above would require manufacturers to submit technical details
of each monitor (e.g., how each monitor worked, when the monitor would
run), we would still need some assurance that the manufacturer's OBD
monitors are indeed calibrated correctly and are able to detect a
malfunction before an emissions threshold is exceeded. Thus, we are
proposing that manufacturers conduct certification demonstration
testing of the major monitors to verify the malfunction threshold
values. This testing would be required on one to three demonstration
engines per year. Before receiving a certificate of compliance, the
manufacturer would be required to submit documentation and emissions
data demonstrating that the major OBD monitors are able to detect a
malfunction when emissions exceed the emissions thresholds. On each
demonstration engine, this testing would consist of the following two
elements:
Testing the OBD system with ``threshold'' components
(i.e., components that are deteriorated or malfunctioning right at the
threshold required for MIL illumination); and,
Testing the OBD system with ``worst case'' components.
This element of the demonstration test would have to be done for the
DPF and any NOX aftertreatment system only.
By testing with both threshold components (i.e., the best
performing malfunctioning components) and with worst case components
(i.e., the worst performing malfunctioning components), we would be
better able to verify that the OBD system should perform as expected
regardless of the level of deterioration of the component. This could
become increasingly important with new technology aftertreatment
devices that could be subject to complete failure (such as DPFs) or
even to tampering by vehicle operators looking to improve fuel economy
or vehicle performance. We believe that, given the likely combinations
of emissions control hardware, a diesel engine manufacturer would
likely need to conduct 8 to 10 emissions tests per demonstration engine
to satisfy these requirements and a gasoline engine manufacturer would
likely need to conduct five to seven emissions tests per demonstration
engine.\74\
---------------------------------------------------------------------------
\74\ For diesel engines these would include: the fuel system;
misfire (HCCI engines); EGR, turbo boost control, DPF,
NOX adsorber or SCR system, NMHC catalyst, exhaust gas
sensors, VVT, and possible other emissions controls (see section
II.D.5). For gasoline engines these would include: the fuel system,
misfire, EGR, cold start strategy, secondary air system, catalyst,
exhaust gas sensors, VVT, and possible other emissions controls (see
section II.D.5). Some of these may require more than one emissions
test while others may not require any due to the use of a functional
monitor rather than an emissions threshold monitor.
---------------------------------------------------------------------------
[[Page 3278]]
1. Selection of Test Engines
To minimize the test burden on manufacturers, we are proposing that
this testing be done on only one to three demonstration engines per
year per manufacturer rather than requiring that all engines be tested.
Such an approach should still allow us to be reasonably sure that
manufacturers have calibrated their OBD systems correctly on all of
their engines. This also spreads the test burden over several years and
allows manufacturers to better utilize their test cell resources. This
approach is consistent with our approach to demonstration testing to
existing emissions standards where a parent engine is chosen to
represent each engine family and emissions test data for only that
parent engine are submitted to EPA.\75\
---------------------------------------------------------------------------
\75\ For over 14,000 pound OBD, we are proposing a different
definition of a ``parent'' engine than is used for emissions
certification. This is discussed at length in section II.G.
---------------------------------------------------------------------------
The number of demonstration engines manufacturers would be required
to test would be aligned with the phase-in of OBD in the 2010 and 2013
model years and based on the year and the total number of engine
families the manufacturer would be certifying for that model year.
Specifically, for the 2010 model year when a manufacturer is only
required to implement OBD on a single engine family, demonstration
testing would be required on only one engine (a single engine rating
within the one engine family). This would be the OBD parent rating as
discussed in section II.G. For the 2013 model year, manufacturers would
be required to conduct demonstration testing on one to three engines
per year (i.e., one to three OBD parent ratings). The number of parent
ratings would be chosen depending on the total number of engine
families certified by the manufacturer. A manufacturer certifying one
to five engine families in the given year would be required to test one
demonstration engine. A manufacturer certifying six to ten engine
families in the given year would be required to test two demonstration
engines, and a manufacturer certifying more than ten engine families in
the given year would be required to test three demonstration engines.
For the 2016 and subsequent model years, we would work closely with
CARB staff and the manufacturer to determine the parent ratings so that
the same ratings are not acting as the parents every year. In other
words, our definitions for the OBD parent ratings as discussed here
apply only during the years 2010 through 2012 and again for the years
2013 through 2015.
Given the difficulty and expense in removing an in-use engine from
a vehicle for engine dynamometer testing, this demonstration testing
would likely represent nearly all of the OBD emission testing that
would ever be done on these engines. Requiring a manufacturer who is
fully equipped to do such testing, and already has the engines on
engine dynamometers for emission testing, to test one to three engines
per year would be a minimal testing burden that provides invaluable
and, in a practical sense, otherwise unobtainable proof of compliance
with the OBD emissions thresholds.
Regarding the selection of which engine ratings would have to be
demonstrated, manufacturers would be required to submit descriptions of
all engine families and ratings planned for the upcoming model year. We
would review the information and make the selection(s) in consultation
with CARB staff and the manufacturer. For each engine family and
rating, the information submitted by the manufacturer would need to
identify engine model(s), power ratings, applicable emissions standards
or family emissions limits, emissions controls on the engine, and
projected engine sales volume. Factors that would be used in selecting
the one to three engine ratings for demonstration testing include, but
are not limited to, new versus old/carryover engines, emissions control
system design, possible transition point to more stringent emissions
standards and/or OBD emissions thresholds, and projected sales volume.
2. Required Testing
Regarding the actual testing, the manufacturer would be required to
perform ``single fault'' testing using the applicable test procedure
and with the appropriate components/systems set at the manufacturer
defined malfunction criteria limits for the following monitors:
For diesel engines: Fuel system; misfire; EGR; turbo boost
control; NMHC catalyst; NOX catalyst/adsorber; DPF; exhaust
gas sensors; VVT; and any other monitor that would fall within the
discussion of section II.D.5.
For gasoline engines: Fuel system; misfire; EGR; cold
start strategy; secondary air; catalyst; exhaust gas sensors; VVT; and
any other monitor that would fall within the discussion of section
II.D.5.
Such ``single fault'' testing would require that, when performing a
test for a specific parameter, that parameter must be operating at the
malfunction criteria limit while all other parameters would be
operating within normal characteristics (unless the malfunction
prohibits some other parameter from operating within its normal
characteristics). Also, the manufacturer would be allowed to use
computer modifications to cause the specific parameter to operate at
the malfunction limit provided the manufacturer can demonstrate that
the computer modifications produce test results equivalent to an
induced hardware malfunction. Lastly, for each of these testing
requirements, wherever the manufacturer has established that only a
functional check is required because no failure or deterioration of the
specific tested component/system could result in an engine's emissions
exceeding the applicable emissions thresholds, the manufacturer would
not be required to perform a demonstration test. In such cases, the
manufacturer could simply provide the data and/or engineering analysis
used to determine that only a functional test of the component/system
was required.
Manufacturers required to submit data from more than one engine
rating would be granted some flexibility by allowing the data to be
collected under less rigorous testing requirements than the official
FTP or SET certification test. That is, for the possible second and
third engine ratings required for demonstration testing, manufacturers
would be allowed to submit data using internal sign-off test procedures
that are representative of the official FTP or SET in lieu of running
the official test. Commonly used procedures include the use of engine
emissions test cells with less rigorous quality control procedures than
those required for the FTP or SET or the use of forced cool-downs to
minimize time between tests. Manufacturers would still be liable for
meeting the OBD emissions thresholds on FTPs and/or SETs conducted in
full accordance with the Code of Federal Regulations. Nonetheless, this
latitude would allow them to use some short-cut methods that they have
developed to assure themselves that the system is calibrated to the
correct level without incurring the additional testing cost and burden
of running the official FTP or SET on every demonstration engine.
For the demonstration engine(s), a manufacturer would be required
to use an engine(s) aged for a minimum of 125
[[Page 3279]]
hours plus exhaust aftertreatment devices aged to be representative of
full useful life. Manufacturers would be expected to use, subject to
approval, an aging process that ensures that deterioration of the
exhaust aftertreatment devices is stabilized sufficiently such that it
properly represents the performance of the devices at the end of their
useful life.
3. Testing Protocol
We are proposing that the manufacturer be allowed to use any
applicable test cycle for preconditioning test engines prior to
conducting each of the emissions tests discussed above. Additional
preconditioning can be done if the manufacturer has provided data and/
or engineering analyses that demonstrate that additional
preconditioning is necessary.
The manufacturer would then set the system or component of interest
at the criteria limit(s) prior to conducting the applicable
preconditioning cycle(s). If more than one preconditioning cycle is
being used, the manufacturer may adjust the system or component of
interest prior to conducting the subsequent preconditioning cycle.
However, the manufacturer may not replace, modify, or adjust the system
or component of interest following the last preconditioning cycle.
After preconditioning, the test engine would be operated over the
applicable test cycle to allow for the initial detection of the tested
system or component malfunction. This test cycle may be omitted from
the testing protocol if it is unnecessary. If required by the
designated monitoring strategy, a cold soak may be performed prior to
conducting this test cycle. The test engine would then be operated over
the applicable exhaust emission test.
A manufacturer required to test more than one test engine may use
internal calibration sign-off test procedures (e.g., forced cool downs,
less frequently calibrated emission analyzers) instead of official test
procedures to obtain this emissions test data for all but one of the
required test engines. However, the manufacturer should use sound
engineering judgment to ensure that the data generated using such
alternative test/sign-off procedures are good data because
manufacturers would still be responsible for meeting the malfunction
criteria when emissions tests are performed in accordance with official
test procedures.
Manufacturers would be allowed to use alternative testing
protocols, even chassis testing, for demonstration of MIL illumination
if the engine dynamometer emissions test cycle does not allow all of a
monitor's enable conditions to be satisfied. Manufacturers wanting to
do so would be required to demonstrate the technical necessity for
using their alternative test cycle and that using it demonstrates that
the MIL would illuminate during in-use operation with the
malfunctioning component.
4. Evaluation Protocol
For all demonstration tests on parent engines, we would expect that
the MIL would activate upon detecting the malfunctioning system or
component, and that it should occur before the end of the first engine
start portion of the emissions test. If the MIL were to activate prior
to emissions exceeding the applicable malfunction criteria, no further
demonstration would be required. With respect to the misfire monitor
demonstration test, if the manufacturer has elected to use the minimum
misfire malfunction criterion of one percent (as is allowed), then no
further demonstration would be required provided the MIL were to
illuminate during a test with an implanted misfire of one percent.
If the MIL does not activate when the system or component being
tested is set at its malfunction criteria limits, then the criteria
limits or the OBD system would not be considered acceptable. Retesting
would be required with more tightly controlled criteria limits (i.e.,
recalibrated limits) and/or another suitable system or component that
would result in MIL activation. If the criteria limits are
recalibrated, the manufacturer would be required to confirm that the
systems and components that were tested prior to recalibration would
still function properly and as required.
5. Confirmatory Testing
We may choose to confirmatory test a demonstration engine to verify
the emissions test data submitted by the manufacturer. Any such
confirmatory testing would be limited to the engine rating represented
by the demonstration engine(s) (i.e., the parent engine(s)). To do so,
we, or our designee, would install appropriately deteriorated or
malfunctioning components (or simulate a deteriorated or malfunctioning
component) in an otherwise properly functioning engine of the same
engine family and rating as the demonstration engine. Such confirmatory
testing would be done on those OBD monitors for which demonstration
testing had been conducted as described in this section. The
manufacturer would be required to make available, upon Administrator
request, a test engine and all test equipment--e.g., malfunction
simulators, deteriorated components--necessary to duplicate the
manufacturer's testing.
D. Deficiencies
Our under 14,000 pound OBD requirements have contained a deficiency
provision for years. The OBD deficiency provision was first introduced
on March 23, 1995 (60 FR 15242), and was revised on December 22, 1998
(63 FR 70681). Consistent with that provision, we are proposing a
deficiency provision for over 14,000 pound OBD. We believe that, like
has occurred and even still occurs with under 14,000 pound OBD, some
manufacturers will encounter unforeseen and generally last minute
problems with some of their OBD monitoring strategies despite having
made a good faith effort to comply with the requirements. Therefore, we
are proposing a provision that would permit certification of an over
14,000 pound OBD system with ``deficiencies'' in cases where a good
faith effort to fully comply has been demonstrated. In making
deficiency determinations, we would consider the extent to which the
proposed OBD requirements have been satisfied overall based on our
review of the certification application, the relative performance of
the given OBD system compared to systems that truly are fully compliant
with the proposed OBD requirements, and a demonstrated good-faith
effort on the part of the manufacturer to both meet the proposed
requirements in full and come into full compliance as expeditiously as
possible.
We believe that having the proposed deficiency provision is
important because it would facilitate OBD implementation by allowing
for certification of an engine despite having a relatively minor
shortfall. Note that we do not expect to certify engines with OBD
systems that have more than one deficiency, or to allow carryover of
any deficiency to the following model year unless it can be
demonstrated that correction of the deficiency requires hardware and/or
software modifications that cannot be accomplished in the time
available, as determined by the Administrator.\76\ Nonetheless, we
recognize that there may be situations where more than one deficiency
is necessary and appropriate, or where carry-over of a deficiency or
deficiencies for more than one year is necessary and
[[Page 3280]]
appropriate. In such situations, more than one deficiency, or carry-
over for more than one year, may be approved, provided the manufacturer
has demonstrated an acceptable level of effort toward full OBD
compliance. Most importantly, the deficiency provisions cannot be used
as a means to avoid compliance or delay implementation of any OBD
monitors or as a means to compromise the overall effectiveness of the
OBD program.
---------------------------------------------------------------------------
\76\ The CARB HDOBD rulemaking has a provision to charge fees
associated with OBD deficiencies 13 CCR 1971.1(k)(3), Docket
ID EPA-HQ-OAR-2005-0047-0006. We have never had and are not
proposing any such fee provision.
---------------------------------------------------------------------------
There has often been some confusion by manufacturers regarding what
CARB has termed ``retroactive'' deficiencies. The CARB rule states
that, ``During the first 6 months after commencement of normal
production, manufacturers may request that the Executive Officer grant
a deficiency and amend an engine's certification to conform to the
granting of the deficiencies for each aspect of the monitoring system:
(a) Identified by the manufacturer (during testing required by section
(l)(2) or any other testing) to be functioning different than the
certified system or otherwise not meeting the requirements of any
aspect of section 1971.1; and (b) reported to the Executive Officer.''
\77\ We have never had and are not proposing any such retroactive
deficiency provision. We have regulations in place that govern
situations, whether they be detected by EPA or by the manufacturer,
where in-use vehicles or engines are determined to be functioning
differently than the certified system.\78\ We refer to these
regulations as our defect reporting requirements and manufacturers are
required to comply with these regulations, even for situations deemed
by CARB to be ``retroactive'' deficiencies, unless the defect is
corrected prior to the sale of engines to an ultimate purchaser. In
other words, a retroactive deficiency granted by the Executive Officer
does not preclude a manufacturer from complying with our defect
reporting requirements.
---------------------------------------------------------------------------
\77\ See 13 CFR 1971.1(k)(6)), Docket ID EPA-HQ-OAR-
2005-0047-0006.
\78\ See 40 CFR 85.1903.
---------------------------------------------------------------------------
E. Production Evaluation Testing
The OBD system is a complex software and hardware system, so there
are many opportunities for unintended interactions that can result in
certain elements of the system not working as intended. We have seen
many such mistakes in the under 14,000 pound arena ranging from OBD
systems that are unable to communicate any information to a scan tool
to monitors that are unable to store a DTC and illuminate the MIL.
While over 14,000 pound heavy-duty vehicles are very different from
light-duty vehicles in terms of emission controls and OBD monitoring
strategies, among other things, these types of problems do not depend
on these differences and, as such, are as likely to occur with over
14,000 pound OBD as they are with under 14,000 pound OBD. Additionally,
we believe that there is great value in having manufacturers self-test
actual production end products that operate on the road, as opposed to
pre-production products, where errors can be found in individual
subsystems that may work fine by themselves but not when integrated
into a complete product (e.g., due to mistakes like improper wiring).
Therefore, we are proposing that manufacturers self-test a small
fraction of their product line to verify compliance with the OBD
requirements. The test requirements are divided into three distinct
sections with each section representing a test for a different portion
of the OBD requirements. These three sections being: compliance with
the applicable SAE and/or ISO standardization requirements; compliance
with the monitoring requirements for proper DTC storage and MIL
illumination; and, compliance with the in-use monitoring performance
ratios.
1. Verification of Standardization Requirements
An essential part of the OBD system is the requirement for
standardization. The proposed standardization requirements include
items as simple as the location and shape of the diagnostic connector
(where technicians can ``plug in'' a scan tool to the onboard computer)
to more complex subjects concerning the manner and format in which DTC
information is accessed by technicians via a ``generic'' scan tool.
Manufacturers must meet these standardization requirements to
facilitate the success of the proposed OBD program because they ensure
consistent access by all repair technicians to the stored information
in the onboard computer. The need for consistency is even greater when
considering the potential use of OBD system checks in inspection and
maintenance (I/M) programs for heavy-duty. Such OBD base I/M checks
would benefit from having access to the diagnostic information in the
onboard computer via a single ``generic'' scan tool instead of
individual tools for every make and model of truck that might be
inspected. For OBD based inspections to work effectively and
efficiently, all engines/vehicles must be designed and built to meet
all of the applicable standardization requirements.
While we anticipate that the vast majority of vehicles would comply
with all of the standardization requirements, some problems involving
the communication between vehicles and ``generic'' scan tools are
likely to occur in the field. The cause of such problems could range
from differing interpretations of the existing standardization
requirements to possible oversights by design engineers or hardware
inconsistencies or even last-minute production changes on the assembly
line.
To minimize the chance for such problems on future over 14,000
pound trucks, we are proposing that engine manufacturers be required to
test a sample of production vehicles from the assembly line to verify
that the vehicles have indeed been designed and built to the required
specifications for communication with a ``generic'' scan tool. We are
proposing that manufacturers be required to test complete vehicles to
ensure that they comply with some of the basic ``generic'' scan tool
standardization requirements, including those that are essential for
proper inspection in an I/M setting. Ideally, manufacturers would be
required to test one vehicle for each truck and engine model
combination that is introduced into commerce. However, for a large
engine manufacturer, this can be in the neighborhood of 5,000 to 10,000
unique combinations making it unreasonable to require testing of every
combination. Therefore, we are proposing that manufacturers test 10
such combinations per engine family. Given that a typical engine family
has roughly five different engine ratings, this works out to testing
only around two vehicles per engine rating.
More specifically, manufacturers would be required to test one
vehicle per software ``version'' released by the manufacturer. With
proper demonstration, manufacturers would be allowed to group different
calibrations together to be demonstrated by a common vehicle. Prior to
acquiring these data, the proposal would require engine manufacturers
to submit for approval a test plan verifying that the vehicles
scheduled for testing would be representative of all vehicle
configurations (e.g., each engine control module variant coupled with
and without the other available vehicle components that could affect
scan tool communication such as automatic transmission or hybrid
powertrain control modules). The plan would have to include details on
all the different applications and configurations that would be tested.
[[Page 3281]]
As noted, manufacturers would be required to conduct this testing
on actual production vehicles, not stand-alone engines. This is
important since controllers that work properly in a stand alone setting
(e.g., the engine before it is installed in a vehicle) may have
interaction problems when installed and attempting to communicate with
other vehicle controllers (e.g., the transmission controller). In such
a case, separate testing of the controllers would be blind to the
problem. Since heavy-duty engine manufacturers are expected to sell the
same engine (with the same calibration) to various vehicle
manufacturers who would put them in different final products (e.g.,
with different transmission control modules), the same communication
problem would be expected in each final product.
This testing should occur soon enough in the production cycle to
provide manufacturers with early feedback regarding the existence of
any problems and time to resolve the problem prior to the entire model
year's products being introduced into the field. We are proposing that
the testing be done and the data submitted to us within either three
months of the start of normal engine production or one month of the
start of vehicle production, whichever is later.
To be sure that all manufacturers are testing vehicles to the same
level of stringency, we are proposing that engine manufacturers submit
documentation outlining the testing equipment and methods they intend
to use to perform this testing. We anticipate that engine manufacturers
and scan tool manufacturers would probably develop a common piece of
hardware and software that could be used by all engine manufacturers at
the end of the vehicle assembly line to meet this requirement. Two
different projects (SAE J1699 and LOC3T) have developed such equipment
in response to California OBD II requirements.\79\ The equipment is
currently being used to test 2005 and 2006 model year vehicles under
14,000 pounds. We believe that similar equipment could be developed for
vehicles over 14,000 pounds in time for the 2013 model year. Ideally,
the equipment and the test procedure would verify each and every
requirement of the communication specifications including the various
physical layers, message structure, response times, and message
content. Presumably, any such verification equipment would not replace
the function of existing ``generic'' scan tools used by repair
technicians or I/M inspectors. The equipment would likely be custom-
designed and be used for the express purpose of this assembly line
testing (i.e., it would not include all of the necessary diagnostic
features needed by repair technicians).
---------------------------------------------------------------------------
\79\ 13 CCR 1968.2, August 11, 2006, Docket ID EPA-HQ-
OAR-2005-0047-0005.
---------------------------------------------------------------------------
2. Verification of Monitoring Requirements
As noted above, the OBD system is a complex software and hardware
system, so there are many opportunities for unintended interactions
that can result in certain elements of the system not working as
intended. The causes of possible problems vary from simple typing
errors in the software code to component supplier hardware changes late
in development or just prior to start of production. Given the
complexity of OBD monitors and their associated algorithms, there can
be thousands of lines of software code required to meet the diagnostic
requirements. Implementing that code without interfering with the
software code required for normal operation is and will be a very
difficult task with many opportunities for human error. We expect that
manufacturers will conduct some validation testing on end products to
ensure that there are no problems that would be noticed by the vehicle
operator. We believe that manufacturers should include in such
verification testing an evaluation of the OBD system (e.g., does the
MIL illuminate as intended in response to a malfunction?).
Therefore, we are proposing that engine manufacturers be required
to perform a thorough level of validation testing on at least one
production vehicle and up to two more production engines per model
year. The production vehicles/engines required for testing would have
to be equipped with/be from the same engine families and ratings as
used for the certification demonstration testing described in section
VIII.B.3. If a manufacturer demonstrated one, two, or three engines for
certification, then at least one production vehicle and perhaps an
additional one to two engines would have to be tested, respectively. We
would work with the manufacturer and CARB staff to determine the actual
vehicles and engines to test.
The testing itself would consist of implanting or simulating
malfunctions to verify that virtually every single engine-related OBD
monitor on the vehicle correctly identifies the malfunction, stores an
appropriate DTC, and illuminates the MIL. Manufacturers would not be
required to conduct any emissions testing. Instead, for those
malfunctions designed against an emissions threshold, the manufacturer
would simply implant or simulate a malfunction and verify detection,
DTC storage, and MIL illumination. Actual ``threshold'' parts would not
be needed for such testing. Implanted malfunctions could use severely
deteriorated parts if desired by the manufacturer since the point of
the testing is to verify detection, DTC storage, and MIL illumination.
Upon submitting the data to the Administrator, the manufacturer would
be required to also provide a description of the testing and the
methods used to implant or simulate each malfunction. Note that testing
of specific monitors would not be required if the manufacturer can show
that no possible test exists that could be done on that monitor without
causing physical damage to the production vehicle. We are proposing
that the testing be completed and reported to us within six months
after the manufacturer begins normal engine production. This should
provide early feedback on the performance of every monitor on the
vehicle prior to too many entering production. Upon good cause, we may
extend the time period for testing.
Note that, in their HDOBD rule,\80\ CARB allows, as an incentive to
perform a thorough validation test, a manufacturer to request that any
problem discovered during this self-test be treated as a
``retroactive'' deficiency. As discussed in section VIII.B.4, we do not
have a provision for retroactive deficiencies. Importantly, a
retroactive deficiency granted by the Executive Officer does not
preclude a manufacturer from complying with our defect reporting
requirements. This issue was discussed in more detail in section
VIII.B.4.
---------------------------------------------------------------------------
\80\ 13 CCR 1971.1, Docket ID EPA-HQ-OAR-2005-0047-
0006.
---------------------------------------------------------------------------
3. Verification of In-Use Monitoring Performance Ratios
We are proposing that manufacturers track the performance of
several of the most important monitors on the engine to determine how
often they are monitoring during in-use operation. These requirements
are discussed in more detail in section II.E. To summarize that
discussion, monitors would be expected to execute in the real world and
meet a minimum acceptable performance level determined as the ratio of
the number of good monitoring events to the number of actual trips. The
ratio being proposed is 10 percent, meaning that monitors should
execute during at least 10 percent of the trips taken by the engine/
vehicle. Monitors
[[Page 3282]]
that perform below the minimum ratio would be subject to remedial
action and possibly recall. However, the minimum ratio is not effective
until the 2013 and later model years. For the 2010 through 2012 model
year engines certified to today's proposed OBD requirements, we are
proposing that the data be collected even though the minimum ratio is
not yet effective. The data gathered on these engines will help to
determine whether the 10 percent ratio is appropriate for all
applications and, if not, we would intend to propose a change to the
proposed requirement to reflect that learning.
We are proposing that manufacturers gather these data on production
vehicles rather than engines. Since not every vehicle can be evaluated,
we are proposing that manufacturers generate groups of engine/vehicle
combinations to ensure adequate representation of the fleet.
Specifically, manufacturers would be required to separate production
vehicles into monitoring performance groups based on the following
criteria and submit performance ratio data representative of each
group:
Emission control system architecture type--All engines
that use the same or similar emissions control system architecture and
associated monitoring system would be in the same emission architecture
category. By architecture we mean engines with EGR+DPF+SCR, or
EGR+DPF+NOX Adsorber, or EGR+DPF-only, etc.
Application type--Within an emission architecture
category, engines would be separated by vehicle application. The
separate application categories would be based on three
classifications: engines intended primarily for line-haul chassis
applications, engines intended primarily for urban delivery chassis
applications, and all other engines.
We are proposing that these data be submitted to us within 12
months of the production vehicles entering the market. Upon submitting
the collected data to us, the manufacturer would also be required to
provide a detailed description of how the data were gathered, how
vehicles were grouped to represent sales of their engines, and the
number of engines tested per monitoring performance group.
Manufacturers would be required to submit performance ratio data from a
sample of at least 15 vehicles per monitoring performance group. For
example, a manufacturer with two emission control system architectures
sold into each of the line-haul, urban delivery, and ``other''
groupings, would be required to submit data on up to 90 vehicles (i.e.,
2 x 3 x 15). We are proposing that these data be collected every year.
Some manufacturers may find it easiest to collect data from vehicles
that come in to its authorized repair facilities for routine
maintenance or warranty work during the time period required, while
others may find it more advantageous to hire a contractor to collect
the data. Upon good cause, we may extend the time period for testing.
As stated before, the data collected under this program are
intended primarily to provide an early indication that the systems are
working as intended in the field, to provide information to ``fine-
tune'' the proposed requirement to track the performance of monitors,
and to provide data to be used to develop a more appropriate minimum
ratio for future regulatory revisions. The data are not intended to
substitute for testing that we would perform for enforcement reasons to
determine if a manufacturer is complying with the minimum acceptable
performance ratios. In fact, the data collected would not likely meet
all the required elements for testing to make an official determination
that the system is noncompliant. As such, we believe the testing would
be of most value to manufacturers since monitor performance problems
can be corrected prior to EPA conducting a full enforcement action that
could result in a recall.
IX. What are the Issues Concerning Inspection and Maintenance Programs?
A. Current Heavy-Duty I/M Programs
While there are currently no regulatory requirements for heavy-duty
inspection and maintenance (I/M), and no State Implementation Plan
(SIP) credit given for heavy-duty I/M, a recent review shows that
programs in the United States as well as abroad are currently testing
heavy-duty diesel and heavy-duty gasoline vehicles as part of their
Inspection and Maintenance programs. A recent study found that the
mandated vehicle emission I/M programs in the CAAA of 1990, originally
required in areas where ambient levels of ozone and CO exceeded the
national standards, are being utilized as a framework as diesel PM
becomes increasingly recognized as an important health concern in the
United States.\81\ Some countries outside the U.S., particularly
developing countries, have been seeking to improve air quality by
implementing both light-duty and heavy-duty I/M programs.
---------------------------------------------------------------------------
\81\ Review of Light-Duty Diesel and Heavy-Duty Diesel/Gasoline
Inspection Programs, St. Denis and Lindner, Journal of the Air and
Waste Management Association, December 2005.
---------------------------------------------------------------------------
In the U.S., the light-duty fleet has become cleaner. As a result,
heavy-duty vehicles are responsible for an increasing contribution of
the mobile source emission inventory. EPA has responded to the
increased contribution by promulgating technology-promoting standards,
to be phased in during the years leading up to 2010. Some non-
attainment areas are implementing HD vehicle I/M programs to improve
their regional air quality. The current tailpipe emissions measurements
result in a number of issues, so other technologies such as remote
sensing are being examined. Interrogation of the OBD system on over
14,000 pound vehicles would likely be a candidate I/M test method.
As of 2004, according to the aforementioned study, many I/M
programs in the U.S. have developed a wide range of emission tests for
HD diesel vehicles and HD gasoline vehicles. 19 States currently test
HD diesel vehicles (these are: AZ, CA, CO, CT, ID, IL, KY, ME, MD, MA,
NV, NH, NJ, NM, NY, OH, UT, VT, WA); 25 states test HD gasoline
vehicles (these are: AK, AZ, CA, CO, CT, ID, IL, IN, KY, MD, MA, NV,
NJ, NM, NY, NC, OH, OR, PA, TN, TX, UT, VA, WA, WI). Canada, China,
Singapore, Sweden, and the United Kingdom test HD diesel vehicles.
Lastly, Germany, Singapore, and Sweden test HD gasoline vehicles.
Whether or not voluntary or regulated inspection and maintenance
programs become prominent, heavy-duty OBD should be designed to allow
ease of interrogation to maximize the potential of this technology to
help realize environmental benefit. There is evidence that localities
are utilizing this strategy in their air quality protection programs.
There is also a wealth of light-duty OBD experience to support making
an I/M-type test as user-friendly as possible so technician training
and scan tool designs do not limit the ability to assess a vehicle's
status.
B. Challenges for Heavy-Duty I/M
There are a number of challenges that are being discovered as
programs implement heavy-duty I/M. Existing HD I/M programs utilize of
a number of different emission test types, such as snap-idle testing
(based on SAE J1667), loaded cruise testing (chassis dynamometer), ASM
testing, Transient IMXXX, Two-Speed Idle or Curb Idle, and Lug-down
testing. Projections of heavy-duty vehicle inventory contributions for
VOC, NOX, PM, and toxics have substantiated the need for
more stringent regulations. Repairs
[[Page 3283]]
based on individual emission test types, such as opacity testing, may
target and reduce one pollutant (e.g., PM) while neglecting or
increasing others (e.g., NOX). A sound test should
effectively control all harmful pollutants, thus must be able to
measure multiple pollutants--specifically PM and NOX
emissions.
Systems capable of measuring both pollutants at the same time have
to date been prohibitively expensive for I/M programs, and
traditionally require a heavy-duty dynamometer so that vehicles can be
tested under load. Recent work has begun to investigate the use of
remote sensing and other technologies for measuring heavy-duty gaseous
and PM emissions. While this technology has not yet been routinely
implemented in HD vehicle I/M programs to date, the impetus to identify
more robust or user-friendly emission testing strategies exists.
Portable emissions measurement systems (PEMS) are not really conducive
to an I/M environment at this time because the units are very costly,
require a great deal of expertise to operate, and require considerable
time for completing a test. Such systems are best suited for intensive
analysis of emissions performance on a limited number of vehicles
rather than the widespread testing of nearly all vehicles as is the
attempt in most I/M programs. All these factors heighten the potential
that OBD systems will be utilized in I/M programs for vehicles over
14,000 pounds.
C. Heavy-Duty OBD and I/M
Heavy-duty OBD should be designed with the anticipation that there
may be new use of OBD to help insure local or regional emission
benefits. If multiple individuals are querying OBD, standardization of
testing equipment and protocol, and information format and availability
should be considered to maximize the effective use of this technology.
Many of the lessons learned from the use of light-duty OBD in I/M
programs point to a need to ensure standard protocols for testing, so
that test equipment and data collection requirements can be
accommodated in system designs. Along with common connectors, data
formats, and specific parameter monitoring requirements, future
technologies enabling standardization of data stream logic (e.g.,
built-in checks, broadcasted updates, etc.) and other currently non-
existing strategies may be attractive to minimize training requirements
for test personnel and data management for model year-specific
information.
Due to the regional or national registrations of many heavy-duty
vehicles, there is the potential that eventual I/M use of OBD to
control heavy-duty vehicle emission exceedences could be at the fleet
or corporate level, rather than at the state level as is the current
light-duty convention. Stakeholders will need to inform the debate but
today's HD I/M programs may not follow the same development pattern as
light-duty I/M programs did a decade ago. The lessons learned from
light-duty OBD I/M should be complemented with early data on HD I/M
programs being piloted in the U.S. and globally.
As one example, Ontario's Ministry of the Environment has prepared
a report on their Heavy-Duty Drive Clean program. This study developed
estimates of emissions benefits for inspected diesel vehicles and
compares them to estimated baseline emissions for the case with no
Drive Clean program, for calendar years 2000, 2001, and 2002. According
to this study, over the three years of the program the total
accumulated emission reductions generated by the program's operation
were estimated to be 1092 tonnes of PM10 emissions, 654 tonnes of HC
emissions, and 721 tonnes of NOX emissions.\82\ This
particular study utilized opacity testing, and compared failed and
fixed vehicles for different model year vehicles and for different
weight classes. The malperformance model developed originally by Radian
Corporation for ARB in 1986 was utilized since the statistical
correlation between smoke opacity an mass emissions is weak, especially
in newer vehicles; and the EPA MOBILE model assume zero deterioration
of emissions for most HD diesel engines, thereby implying no benefit
for I/M. The relationship between maintenance and emission
deterioration is complicated by the use of high efficiency
aftertreatment devices, which lose emission conversion efficiency with
age, so this model's basic premise is likely appropriate only until the
year 2008. Nevertheless, as the benefits of inspection and maintenance
become more clearly articulated, the interest in assessing test
methodologies that provide ease of use as well as multi-pollutant
screening will likely increase. For these reasons consideration of
potential I/M program use of OBD for the heavy-duty fleet is warranted,
and should include lessons-learned from the light-duty fleet as well as
anticipate new strategies for utilizing OBD information.
---------------------------------------------------------------------------
\82\ ``Drive Clean Program Emission Benefit Analysis and
Reporting--Heavy-Duty Diesel Vehicles,'' Canada Ministry of the
Environment, October 2003.
---------------------------------------------------------------------------
We request comment with respect to the level of interest in I/M
programs that make use of the proposed OBD system on over 14,000 pound
vehicles. Specifically, are states interested in I/M for over 14,000
pound vehicles that mirrors existing programs for passenger cars and
other light trucks? For those that might be interested, does the
proposed OBD system meet the needs of their potential I/M program?
X. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review
This action is not a ``significant regulatory action'' under the
terms of Executive Order (EO) 12866 (58 FR 51735, October 4, 1993) and
is, therefore, not subject to review under the EO.
EPA prepared an analysis of the potential costs associated with
this action. This analysis is contained in the technical support
document.\83\ A copy of the analysis is available in the docket and was
summarized in section VI of this preamble.
---------------------------------------------------------------------------
\83\ Draft Technical Support Document, HDOBD NPRM, EPA420-D-06-
006, Docket ID EPA-HQ-OAR-2005-0047-0008.
---------------------------------------------------------------------------
B. Paperwork Reduction Act
The proposed information collection requirements for this action
have been submitted for approval to the Office of Management and Budget
(OMB) under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. The
Information Collection Request (ICR) document prepared by EPA has been
assigned EPA ICR number 1684.09. Under Title II of the Clean Air Act
(42 U.S.C. 7521 et seq.; CAA), EPA is charged with issuing certificates
of conformity for those engines that comply with applicable emission
standards. Such a certificate must be issued before engines may be
legally introduced into commerce. EPA uses certification information to
verify that the proper engine prototypes have been selected and that
the necessary testing has been performed to assure that each engine
complies with emission standards. In addition, EPA also has the
authority under Title II of the Clean Air to ensure compliance by
require in-use testing of vehicles and engines. EPA is proposing to
require additional information at the time of certification to ensure
that that on-board diagnostic (OBD) requirements are being met. EPA is
also proposing that manufacturers conduct and report the results of in-
use testing of the OBD systems to
[[Page 3284]]
demonstrate that they are performing properly. Therefore, EPA is
proposing 207 hours of annual burden per each of the 12 respondents to
conduct the OBD certification, compliance, and in-use testing
requirements proposed by this action. EPA estimates that the total of
the of the 2484 hours of annual cost burden will be $16,018 per
respondent for a total annual industry cost burden for the 12
respondents of $1,236,481.
Burden means the total time, effort, or financial resources
expended by persons to generate, maintain, retain, or disclose or
provide information to or for a Federal agency. technology and systems
for the purposes of collecting, validating, and verifying. This
includes the time needed to review instructions; develop, acquire,
install, and utilize information, processing and maintaining
information, and disclosing and providing information; adjust the
existing ways to comply with any previously applicable instructions and
requirements; train personnel to be able to respond to a collection of
information; search data sources; complete and review the collection of
information; and transmit or otherwise disclose the information.
An agency may not conduct or sponsor, and a person is not required
to respond to a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for EPA's
regulations in 40 CFR are listed in 40 CFR part 9.
To comment on the Agency's need for this information, the accuracy
of the provided burden estimates, and any suggested methods for
minimizing respondent burden, including the use of automated collection
techniques, EPA has established a public docket for this rule, which
includes this ICR, under Docket ID number EPA-HQ-OAR-2005-0047. Submit
any comments related to the ICR for this proposed rule to EPA and OMB.
See the ADDRESSES section at the beginning of this notice for where to
submit comments to EPA. Send comments to OMB at the Office of
Information and Regulatory Affairs, Office of Management and Budget,
725 17th Street, NW., Washington, DC 20503, Attention: Desk Office for
EPA. Since OMB is required to make a decision concerning the ICR
between 30 and 60 days after January 24, 2007, a comment to OMB is best
assured of having its full effect if OMB receives it by February 23,
2007. The final rule will respond to any OMB or public comments on the
information collection requirements contained in this proposal.
C. Regulatory Flexibility Act (RFA), as Amended by the Small Business
Regulatory Enforcement Fairness Act of 1996 (SBREFA), 5 U.S.C. 601 et.
seq.
The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute unless the agency certifies that the
rule will not have a significant economic impact on a substantial
number of small entities. Small entities include small businesses,
small organizations, and small governmental jurisdictions.
For purposes of assessing the impacts of today's proposed rule on
small entities, small entity is defined as: (1) A motor vehicle
manufacturer with fewer than 1,000 employees; (2) a motor vehicle
converter with fewer than 750 employees; (3) a small governmental
jurisdiction that is a government of a city, county, town, school
district or special district with a population of less than 50,000; and
(4) a small organization that is any not-for-profit enterprise which is
independently owned and operated and is not dominant in its field.
After considering the economic impacts of today's proposed rule on
small entities, we have determined that this action would not have a
significant economic impact on a substantial number of small entities.
This proposed rule would not have any adverse economic impact on small
entities. Today's rule places new requirements on manufacturers of
large engines meant for highway use. These are large manufacturers.
Today's rule also changes existing requirements on manufacturers of
passenger car and smaller heavy-duty engines meant for highway use.
These changes place no meaningful new requirements on those
manufacturers.
D. Unfunded Mandates Reform Act
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public
Law 104-4, establishes requirements for federal agencies to assess the
effects of their regulatory actions on state, local, and tribal
governments, and the private sector. Under section 202 of the UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for proposed and final rules with ``Federal mandates'' that
may result in expenditures to state, local, and tribal governments, in
the aggregate, or to the private sector, of $100 million or more for
any single year. Before promulgating a rule for which a written
statement is needed, section 205 of the UMRA generally requires EPA to
identify and consider a reasonable number of regulatory alternatives
and to adopt the least costly, most cost-effective, or least burdensome
alternative that achieves the objectives of the rule. The provisions of
section 205 do not apply when they are inconsistent with applicable
law. Moreover, section 205 allows EPA to adopt an alternative that is
not the least costly, most cost-effective, or least burdensome
alternative if the Administrator publishes with the final rule an
explanation of why such an alternative was not adopted.
Before EPA establishes any regulatory requirement that may
significantly or uniquely affect small governments, including tribal
governments, it must have developed under section 203 of the UMRA a
small government agency plan. The plan must provide for notifying
potentially affected small governments, enabling officials of affected
small governments to have meaningful and timely input in the
development of EPA regulatory proposals with significant Federal
intergovernmental mandates, and informing, educating, and advising
small governments on compliance with the regulatory requirements.
This rule contains no federal mandates (under the regulatory
provisions of Title II of the UMRA) for State, local, or tribal
governments or the private sector. The rule imposes no enforceable
duties on any of these entities. Nothing in the rule would
significantly or uniquely affect small governments. We have determined
that this rule does not contain a federal mandate that may result in
estimated expenditures of more than $100 million to the private sector
in any single year. Therefore, the requirements of the UMRA do not
apply to this action.
E. Executive Order 13132: Federalism
Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August
10, 1999), requires EPA to develop an accountable process to ensure
``meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism implications.''
``Policies that have federalism implications'' is defined in the
Executive Order to include regulations that have ``substantial direct
effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government.''
This proposed rule does not have federalism implications. It will
not have substantial direct effects on the States, on the relationship
between the national
[[Page 3285]]
government and the States, or on the distribution of power and
responsibilities among the various levels of government, as specified
in Executive Order 13132. This proposed rule places new requirements on
manufacturers of large engines meant for highway use and changes
existing requirements on manufacturers of passenger car and smaller
heavy-duty engines meant for highway use. These changes do not affect
States or the relationship between the national government and the
States. Thus, Executive Order 13132 does not apply to this rule.
In the spirit of Executive Order 13132, and consistent with EPA
policy to promote communications between EPA and State and local
governments, EPA specifically solicits comment on this proposed rule
from State and local officials.
F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
Executive Order 13175, entitled ``Consultation and Coordination
with Indian Tribal Governments'' (65 FR 67249, November 9, 2000),
requires EPA to develop an accountable process to ensure ``meaningful
and timely input by tribal officials in the development of regulatory
policies that have tribal implications.'' This proposed rule does not
have tribal implications, as specified in Executive Order 13175.
Today's rule does not uniquely affect the communities of American
Indian tribal governments since the motor vehicle requirements for
private businesses in today's rule would have national applicability.
Furthermore, today's rule does not impose any direct compliance costs
on these communities and no circumstances specific to such communities
exist that would cause an impact on these communities beyond those
discussed in the other sections of today's document. Thus, Executive
Order 13175 does not apply to this rule.
G. Executive Order 13045: Protection of Children From Environmental
Health and Safety Risks
Executive Order 13045, ``Protection of Children from Environmental
Health Risks and Safety Risks'' (62 FR 19885, April 23, 1997) applies
to any rule that: (1) Is determined to be ``economically significant''
as defined under Executive Order 12866; and, (2) concerns an
environmental health or safety risk that EPA has reason to believe may
have a disproportionate effect on children. If the regulatory action
meets both criteria, the Agency must evaluate the environmental health
or safety effects of the planned rule on children, and explain why the
planned regulation is preferable to other potentially effective and
reasonably feasible alternatives considered by the Agency.
This proposed rule is not subject to the Executive Order because it
is not an economically significant regulatory action as defined by
Executive Order 12866, and because the Agency does not have reason to
believe the environmental health or safety risks addressed by this
action present a disproportionate risk to children.
H. Executive Order 13211: Actions That Significantly Affect Energy
Supply, Distribution, or Use
This rule is not subject to Executive Order 13211, ``Actions
Concerning Regulations That Significantly Affect Energy Supply,
Distribution, or Use'' (66 FR 28355, May 22, 2001) because it is not a
significant regulatory action under Executive Order 12866.
I. National Technology Transfer Advancement Act
Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (NTTAA), Section 12(d) of Public Law 104-113, directs EPA
to use voluntary consensus standards in its regulatory activities
unless to do so would be inconsistent with applicable law or otherwise
impractical. Voluntary consensus standards are technical standards
(e.g., materials specifications, test methods, sampling procedures, and
business practices) developed or adopted by voluntary consensus
standards bodies. The NTTAA directs EPA to provide Congress, through
OMB, explanations when the Agency decides not to use available and
applicable voluntary consensus standards.
This proposed rule references technical standards. The technical
standards being proposed are listed in Table II.F-1 of this preamble,
and directions for how they may be obtained are provided in section
II.F.1. EPA welcomes comments on this aspect of the proposed rulemaking
and, specifically, invites the public to identify other potentially-
applicable voluntary consensus standards and to explain why such
standards should be used in this regulation.
XI. Statutory Provisions and Legal Authority
Statutory authority for today's proposed rule is found in the Clean
Air Act, 42 U.S.C. 7401 et seq., in particular, sections 202 and 206 of
the Act, 42 U.S.C. 7521, 7525. This rule is being promulgated under the
administrative and procedural provisions of Clean Air Act section
307(d), 42 U.S.C. 7607(d).
List of Subjects in 40 CFR Part 86
Environmental Protection, Administrative practice and procedure,
Motor vehicle pollution.
Dated: December 11, 2006.
Stephen L. Johnson,
Administrator.
For the reasons set out in the preamble, part 86 of title 40 of the
Code of Federal Regulations is proposed to be amended as follows:
PART 86--CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES
AND ENGINES
1. The authority citation for part 86 continues to read as follows:
Authority: 42 U.S.C. 7401-7671q.
2. Section 86.1 is amended as follows:
a. In the table to paragraph (b)(2) by adding new entries to the
end of the table.
b. In the table to paragraph (b)(5) by adding a new entry to the
end of the table.
Sec. 86.1 Reference materials.
* * * * *
(b) * * *
(2) * * *
------------------------------------------------------------------------
Document No. and name 40 CFR part 86 reference
------------------------------------------------------------------------
* * * * * * *
SAE J1930, Electrical/Electronic 86.010-18
Systems Diagnostic Terms,
Definitions, Abbreviations, and
Acronyms--Equivalent to ISO/TR
15031-2: April 2002.
SAE J1939, MONTH 2006, 86.010-18; 86.010-38
Recommended Practice for a
Serial Control and
Communications Vehicle Network.
SAE J1939-13, MONTH 2006, Off- 86.013-18
Board Diagnostic Connector.
SAE J1962, Diagnostic Connector-- 86.013-18
Equivalent to ISO/DIS.
15031-3: April 2002..............
SAE J1978, OBD II Scan Tool-- 86.010-18
Equivalent to ISO/DIS 15031-4:
April 2002.
[[Page 3286]]
SAE J1979, E/E Diagnostic Test 86.010-18; 86.010-38
Modes--Equivalent to ISO/DIS
15031-5: April 2002.
SAE J2012, Diagnostic Trouble 86.010-18
Code Definitions--Equivalent to
ISO/DIS 15031-6: April 2002.
SAE J2403, Medium/Heavy-Duty E/E 86.007-17; 86.010-18; 86.010-38;
Systems Diagnosis Nomenclature; 86.1806-07
August 2004.
SAE J2534, Recommended Practice 86.010-18; 86.010-38
for Pass-Thru Vehicle
Reprogramming: February 2002.
------------------------------------------------------------------------
* * * * *
(5) * * *
------------------------------------------------------------------------
Document No. and name 40 CFR part 86 reference
------------------------------------------------------------------------
* * * * * * *
ISO 15765-4:2001, Road Vehicles-- 86.010-18
Diagnostics on Controller Area
Network (CAN)--Part 4:
Requirements for emission-
related systems: December 2001.
------------------------------------------------------------------------
* * * * *
3. Section 86.007-17 is added to Subpart A to read as follows:
Sec. 86.007-17 On-board Diagnostics for engines used in applications
less than or equal to 14,000 pounds GVWR.
Section 86.007-17 includes text that specifies requirements that
differ from Sec. 86.005-17. Where a paragraph in Sec. 86.005-17 is
identical and applicable to Sec. 86.007-17, this may be indicated by
specifying the corresponding paragraph and the statement ``[Reserved].
For guidance see Sec. 86.005-17.''
(a)(1) [Reserved]. For guidance see Sec. 86.005-17.
(a)(2) An OBD system demonstrated to fully meet the requirements in
Sec. 86.1806-07 may be used to meet the requirements of this section,
provided that the Administrator finds that a manufacturer's decision to
use the flexibility in this paragraph (a)(2) is based on good
engineering judgment.
(b) introductory text and (b)(1)(i) [Reserved]. For guidance see
Sec. 86.005-17.
(b)(1)(ii) Diesel.
(A) If equipped, catalyst deterioration or malfunction before it
results in exhaust NOX emissions exceeding either: 1.75
times the applicable NOX standard for engines certified to a
NOX FEL greater than 0.50 g/bhp-hr; or, the applicable
NOX FEL+0.5 g/bhp-hr for engines certified to a
NOX FEL less than or equal to 0.50 g/bhp-hr. This
requirement applies only to reduction catalysts; monitoring of
oxidation catalysts is not required. This monitoring need not be done
if the manufacturer can demonstrate that deterioration or malfunction
of the system will not result in exceedance of the threshold.
(b)(1)(ii)(B) and (b)(2) [Reserved]. For guidance see Sec. 86.005-
17.
(b)(3)(i) Oxygen sensors and air-fuel ratio sensors downstream of
aftertreatment devices.
(A) Otto-cycle. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is
higher; or, 1.75 times the applicable NOX standard for
engines certified to a NOX FEL greater than 0.50 g/bhp-hr;
or, the applicable NOX FEL+0.5 g/bhp-hr for engines
certified to a NOX FEL less than or equal to 0.50 g/bhp-hr;
or, 2.5 times the applicable NMHC standard.
(ii) Oxygen sensors and air-fuel ratio sensors upstream of
aftertreatment devices.
(A) Otto-cycle. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is
higher; or, 1.75 times the applicable NOX standard for
engines certified to a NOX FEL greater than 0.50 g/bhp-hr;
or, the applicable NOX FEL+0.5 g/bhp-hr for engines
certified to a NOX FEL less than or equal to .50 g/bhp-hr;
or, 2.5 times the applicable NMHC standard; or, 2.5 times the
applicable CO standard.
(iii) NOX sensors.
(A) Otto-cycle. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding any of the following levels:
The applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is
higher; or, 1.75 times the applicable NOX standard for
engines certified to a NOX FEL greater than 0.50 g/bhp-hr;
or, the applicable NOX FEL+0.5 g/bhp-hr for engines
certified to a NOX FEL less than or equal to 0.50 g/bhp-hr.
(b)(4) [Reserved]. For guidance see Sec. 86.005--17.
(b)(5) Other emission control systems and components.
(i) Otto-cycle. Any deterioration or malfunction occurring in an
engine system or component directly intended to control emissions,
including but not necessarily limited to, the exhaust gas recirculation
(EGR) system, if equipped, the secondary air system, if equipped, and
the fuel control system, singularly resulting in exhaust emissions
exceeding 1.5 times the applicable emission standard or FEL for NMHC,
NOX or CO. For engines equipped with a secondary air system,
a functional check, as described in Sec. 86.005-17(b)(6), may satisfy
the requirements of this paragraph (b)(5) provided the manufacturer can
demonstrate that deterioration of the flow distribution system is
unlikely. This demonstration is subject to Administrator approval and,
if the demonstration and associated functional check are approved, the
diagnostic system must indicate a malfunction when some degree of
secondary airflow is not detectable in the exhaust system during the
check. For engines equipped with positive crankcase ventilation (PCV),
monitoring of the PCV system is not necessary provided the manufacturer
can demonstrate to the Administrator's satisfaction that the PCV system
is unlikely to fail.
(ii) Diesel. Any deterioration or malfunction occurring in an
engine system or component directly intended to control emissions,
including but not necessarily limited to, the exhaust gas
[[Page 3287]]
recirculation (EGR) system, if equipped, and the fuel control system,
singularly resulting in exhaust emissions exceeding any of the
following levels: The applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr
PM, whichever is higher; or, 1.75 times the applicable NOX
standard for engines certified to a NOX FEL greater than
0.50 g/bhp-hr; or, the applicable NOX FEL+0.5 g/bhp-hr for
engines certified to a NOX FEL less than or equal to 0.50 g/
bhp-hr; or, 2.5 times the applicable NMHC standard; or, 2.5 times the
applicable CO standard. A functional check, as described in Sec.
86.005-17(b)(6), may satisfy the requirements of this paragraph (b)(5)
provided the manufacturer can demonstrate that a malfunction would not
cause emissions to exceed the applicable levels. This demonstration is
subject to Administrator approval. For engines equipped with crankcase
ventilation (CV), monitoring of the CV system is not necessary provided
the manufacturer can demonstrate to the Administrator's satisfaction
that the CV system is unlikely to fail.
(b)(6) [Reserved]. For guidance see Sec. 86.005-17.
(b)(7) Performance of OBD functions. Any sensor or other component
deterioration or malfunction which renders that sensor or component
incapable of performing its function as part of the OBD system must be
detected and identified on engines so equipped.
(c), (d), (e), (f), (g), and (h)(1)(i) through (h)(1)(iv)
[Reserved]. For guidance see Sec. 86.005-17.
(h)(1)(v) All acronyms, definitions and abbreviations shall be
formatted according to SAE J1930 ``Electrical/Electronic Systems
Diagnostic Terms, Definitions, Abbreviations, and Acronyms Equivalent
to ISO/TR 15031-2: April 30, 2002'', (Revised, April 2002), or SAE
J2403, ``Medium/Heavy-Duty E/E Systems Diagnosis Nomenclature: August
2004.''
(h)(1)(vi) through (h)(3) [Reserved]. For guidance see Sec.
86.005-17.
(i) Deficiencies and alternative fueled engines. Upon application
by the manufacturer, the Administrator may accept an OBD system as
compliant even though specific requirements are not fully met. Such
compliances without meeting specific requirements, or deficiencies,
will be granted only if compliance would be infeasible or unreasonable
considering such factors as, but not limited to: Technical feasibility
of the given monitor and lead time and production cycles including
phase-in or phase-out of engines or vehicle designs and programmed
upgrades of computers. Unmet requirements should not be carried over
from the previous model year except where unreasonable hardware or
software modifications would be necessary to correct the deficiency,
and the manufacturer has demonstrated an acceptable level of effort
toward compliance as determined by the Administrator. Furthermore, EPA
will not accept any deficiency requests that include the complete lack
of a major diagnostic monitor (``major'' diagnostic monitors being
those for exhaust aftertreatment devices, oxygen sensor, air-fuel ratio
sensor, NOX sensor, engine misfire, evaporative leaks, and
diesel EGR, if equipped), with the possible exception of the special
provisions for alternative fueled engines. For alternative fueled
heavy-duty engines (e.g. natural gas, liquefied petroleum gas,
methanol, ethanol), manufacturers may request the Administrator to
waive specific monitoring requirements of this section for which
monitoring may not be reliable with respect to the use of the
alternative fuel. At a minimum, alternative fuel engines must be
equipped with an OBD system meeting OBD requirements to the extent
feasible as approved by the Administrator.
(j) California OBDII compliance option. For heavy-duty engines used
in applications weighing 14,000 pounds GVWR or less, demonstration of
compliance with California OBD II requirements (Title 13 California
Code of Regulations section 1968.2 (13 CCR 1968.2)), as modified and
released on August 11, 2006, shall satisfy the requirements of this
section, except that compliance with 13 CCR 1968.2(e)(4.2.2)(C),
pertaining to 0.02 inch evaporative leak detection, and 13 CCR
1968.2(d)(1.4), pertaining to tampering protection, are not required to
satisfy the requirements of this section. Also, the deficiency
provisions of 13 CCR 1968.2(k) do not apply. The deficiency provisions
of paragraph (i) of this section and the evaporative leak detection
requirement of Sec. 86.005-17(b)(4) apply to manufacturers selecting
this paragraph for demonstrating compliance. In addition, demonstration
of compliance with 13 CCR 1968.2(e)(15.2.1)(C), to the extent it
applies to the verification of proper alignment between the camshaft
and crankshaft, applies only to vehicles equipped with variable valve
timing.
(k) [Reserved]. For guidance see Sec. 86.005-17.
4. Section 86.007-30 is added to Subpart A to read as follows:
Section 86.007-30 includes text that specifies requirements that
differ from Sec. Sec. 86.094-30, 86.095-30, 86.096-30, 86.098-30,
86.001-30 or 86.004-30. Where a paragraph in Sec. 86.094-30, Sec.
86.095-30, Sec. 86.096-30, Sec. 86.098-30, Sec. 86.001-30 or Sec.
86.004-30 is identical and applicable to Sec. 86.007-30, this may be
indicated by specifying the corresponding paragraph and the statement
``[Reserved]. For guidance see Sec. 86.094-30.'' or ``[Reserved]. For
guidance see Sec. 86.095-30.'' or ``[Reserved]. For guidance see Sec.
86.096-30.'' or ``[Reserved]. For guidance see Sec. 86.098-30.'' or
``[Reserved]. For guidance see Sec. 86.001-30.'' or ``[Reserved]. For
guidance see 86.004-30.''
Sec. 86.007-30 Certification.
(a)(1) and (a)(2) [Reserved]. For guidance see Sec. 86.094-30.
(a)(3)(i) through (a)(4)(ii) [Reserved]. For guidance see Sec.
86.004-30.
(a)(4)(iii) introductory text through (a)(4)(iii)(C) [Reserved].
For guidance see Sec. 86.094-30.
(a)(4)(iv) introductory text [Reserved]. For guidance see Sec.
86.095-30.
(a)(4)(iv)(A)-(a)(9) [Reserved]. For guidance see Sec. 86.094-30.
(a)(10) and (a)(11) [Reserved]. For guidance see Sec. 86.004-30.
(a)(12) [Reserved]. For guidance see Sec. 86.094-30.
(a)(13) [Reserved]. For guidance see Sec. 86.095-30.
(a)(14) [Reserved]. For guidance see Sec. 86.094-30.
(a) (15)-(18) [Reserved]. For guidance see Sec. 86.096-30.
(a)(19) [Reserved]. For guidance see Sec. 86.098-30.
(a)(20) [Reserved]. For guidance see Sec. 86.001-30.
(a)(21) [Reserved]. For guidance see Sec. 86.004-30.
(b)(1) introductory text through (b)(1)(ii)(A) [Reserved]. For
guidance see Sec. 86.094-30.
(b)(1)(ii)(B) [Reserved]. For guidance see Sec. 86.004-30.
(b)(1)(ii)(C) [Reserved]. For guidance see Sec. 86.094-30.
(b)(1)(ii)(D) [Reserved]. For guidance see Sec. 86.004-30.
(b)(1)(iii) and (b)(1)(iv) [Reserved]. For guidance see Sec.
86.094-30.
(b)(2) [Reserved]. For guidance see Sec. 86.098-30.
(b)(3)-(b)(4)(i) [Reserved]. For guidance see Sec. 86.094-30.
(b)(4)(ii) introductory text [Reserved]. For guidance see Sec.
86.098-30.
(b)(4)(ii)(A) [Reserved]. For guidance see Sec. 86.094-30.
(b)(4)(ii)(B)-(b)(4)(iv) [Reserved]. For guidance see Sec. 86.098-
30.
(b)(5)-(e) [Reserved]. For guidance see Sec. 86.094-30.
(f) introductory text through (f)(1)(i) [Reserved]. For guidance
see Sec. 86.004-30.
[[Page 3288]]
(f)(1)(ii) Diesel.
(A) If monitored for emissions performance--a catalyst is replaced
with a deteriorated or defective catalyst, or an electronic simulation
of such, resulting in exhaust emissions exceeding 1.75 times the
applicable NOX standard for engines certified to a
NOX FEL greater than 0.50 g/bhp-hr; or, the applicable
NOX FEL+0.5 g/bhp-hr for engines certified to a
NOX FEL less than or equal to 0.50 g/bhp-hr. This
requirement applies only to reduction catalysts.
(B) If monitored for performance--a particulate trap is replaced
with a trap that has catastrophically failed, or an electronic
simulation of such.
(f)(2) [Reserved]. For guidance see Sec. 86.004-30.
(f)(3)(i) Oxygen sensors and air-fuel ratio sensors downstream of
aftertreatment devices.
(A) Otto-cycle. If so equipped, any oxygen sensor or air-fuel ratio
sensor located downstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If so equipped, any oxygen sensor or air-fuel ratio
sensor located downstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is
higher; or, 1.75 times the applicable NOX standard for
engines certified to a NOX FEL greater than 0.50 g/bhp-hr;
or, the applicable NOX FEL+0.5 g/bhp-hr for engines
certified to a NOX FEL less than or equal to 0.50 g/bhp-hr;
or, 2.5 times the applicable NMHC standard.
(ii) Oxygen sensors and air-fuel ratio sensors upstream of
aftertreatment devices.
(A) Otto-cycle. If so equipped, any oxygen sensor or air-fuel ratio
sensor located upstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If so equipped, any oxygen sensor or air-fuel ratio
sensor located upstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is
higher; or, 1.75 times the applicable NOX standard for
engines certified to a NOX FEL greater than 0.50 g/bhp-hr;
or, the applicable NOX FEL+0.5 g/bhp-hr for engines
certified to a NOX FEL less than or equal to 0.50 g/bhp-hr;
or, 2.5 times the applicable NMHC standard; or, 2.5 times the
applicable CO standard.
(iii) NOX sensors.
(A) Otto-cycle. If so equipped, any NOX sensor is
replaced with a deteriorated or defective sensor, or an electronic
simulation of such, resulting in exhaust emissions exceeding 1.5 times
the applicable standard or FEL for NMHC, NOX or CO.
(B) Diesel. If so equipped, any NOX sensor is replaced
with a deteriorated or defective sensor, or an electronic simulation of
such, resulting in exhaust emissions exceeding any of the following
levels: the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM,
whichever is higher; or, 1.75 times the applicable NOX
standard for engines certified to a NOX FEL greater than
0.50 g/bhp-hr; or, the applicable NOX FEL+0.5 g/bhp-hr for
engines certified to a NOX FEL less than or equal to 0.50 g/
bhp-hr.
(f)(4) [Reserved]. For guidance see Sec. 86.004-30.
(f)(5)(i) Otto-cycle. A malfunction condition is induced in any
emission-related engine system or component, including but not
necessarily limited to, the exhaust gas recirculation (EGR) system, if
equipped, the secondary air system, if equipped, and the fuel control
system, singularly resulting in exhaust emissions exceeding 1.5 times
the applicable emission standard or FEL for NMHC, NOX, or
CO.
(ii) Diesel. A malfunction condition is induced in any emission-
related engine system or component, including but not necessarily
limited to, the exhaust gas recirculation (EGR) system, if equipped,
and the fuel control system, singularly resulting in exhaust emissions
exceeding any of the following levels: the applicable PM FEL+0.04 g/
bhp-hr or 0.05 g/bhp-hr PM, whichever is higher; or, 1.75 times the
applicable NOX standard for engines certified to a
NOX FEL greater than 0.50 g/bhp-hr; or, the applicable
NOX FEL+0.5 g/bhp-hr for engines certified to a
NOX FEL less than or equal to 0.50 g/bhp-hr; or, 2.5 times
the applicable NMHC standard; or, 2.5 times the applicable CO standard.
(f)(6) [Reserved]. For guidance see Sec. 86.004-30.
5. Section 86.010-2 is added to Subpart A to read as follows:
Sec. 86.010-2 Definitions.
The definitions of Sec. 86.004-2 continue to apply to 2004 and
later model year vehicles. The definitions listed in this section apply
beginning with the 2010 model year.
Drive cycle or driving cycle means operation that consists of
engine startup and engine shutoff during which a given onboard
diagnostic (OBD) monitor makes a diagnostic decision. A drive cycle
need not consist of all OBD monitors making a diagnostic decision
during the engine startup and engine shutoff cycle. An engine restart
following an engine shutoff that has been neither commanded by the
vehicle operator nor by the engine control strategy but caused by an
event such as an engine stall may be considered a new drive cycle or a
continuation of the existing drive cycle.
DTC means diagnostic trouble code.
Engine start as used in Sec. 86.010-18 means the point when the
engine reaches a speed 150 rpm below the normal, warmed-up idle speed
(as determined in the drive position for vehicles equipped with an
automatic transmission). For hybrid vehicles or for engines employing
alternative engine start hardware or strategies (e.g., integrated
starter and generators.), the manufacturer may use an alternative
definition for engine start (e.g., key-on) provided the alternative
definition is based on equivalence to an engine start for a
conventional vehicle.
Functional check, in the context of onboard diagnostics, means
verifying that a component and/or system that receives information from
a control computer responds properly to a command from the control
computer.
Ignition cycle as used in Sec. 86.010-18 means a cycle that begins
with engine start, meets the engine start definition for at least two
seconds plus or minus one second, and ends with engine shutoff.
Limp-home operation as used in Sec. 86.010-18 means an operating
mode that an engine is designed to enter upon determining that normal
operation cannot be maintained. In general, limp-home operation implies
that a component or system is not operating properly or is believed to
be not operating properly.
Malfunction means the conditions have been met that require the
activation of an OBD malfunction indicator light and storage of a DTC.
MIL-on DTC means the diagnostic trouble code stored when an OBD
system has detected and confirmed that a malfunction exists (e.g.,
typically on the second drive cycle during which a given OBD monitor
has evaluated a system or component). Industry standards may refer to
this as a confirmed or an active DTC.
[[Page 3289]]
Pending DTC means the diagnostic trouble code stored upon the
detection of a potential malfunction.
Permanent DTC means a DTC that corresponds to a MIL-on DTC and is
stored in non-volatile random access memory (NVRAM). A permanent DTC
can only be erased by the OBD system itself and cannot be erased
through human interaction with the OBD system or any onboard computer.
Previous-MIL-on DTC means a DTC that corresponds to a MIL-on DTC
but is distinguished by representing a malfunction that the OBD system
has determined no longer exists but for which insufficient operation
has occurred to satisfy the DTC erasure provisions.
Potential malfunction means that conditions have been detected that
meet the OBD malfunction criteria but for which more drive cycles are
allowed to provide further evaluation prior to confirming that a
malfunction exists.
Rationality check, in the context of onboard diagnostics, means
verifying that a component that provides input to a control computer
provides an accurate input to the control computer while in the range
of normal operation and when compared to all other available
information.
Similar conditions, in the context of onboard diagnostics, means
engine conditions having an engine speed within 375 rpm, load
conditions within 20 percent, and the same warm up status (i.e., cold
or hot). The manufacturer may use other definitions of similar
conditions based on comparable timeliness and reliability in detecting
similar engine operation.
6. Section 86.010-17 is added to Subpart A to read as follows:
Sec. 86.010-17 On-board Diagnostics for engines used in applications
less than or equal to 14,000 pounds GVWR.
Section 86.010-17 includes text that specifies requirements that
differ from Sec. 86.005-17 and Sec. 86.007-17. Where a paragraph in
Sec. 86.005-17 or Sec. 86.007-17 is identical and applicable to Sec.
86.010-17, this may be indicated by specifying the corresponding
paragraph and the statement ``[Reserved]. For guidance see Sec.
86.005-17.'' or ``[Reserved]. For guidance see Sec. 86.007-17.''
(a) General.
(1) All heavy-duty engines intended for use in a heavy-duty vehicle
weighing 14,000 pounds GVWR or less must be equipped with an on-board
diagnostic (OBD) system capable of monitoring all emission-related
engine systems or components during the applicable useful life. All
monitored systems and components must be evaluated periodically, but no
less frequently than once per applicable certification test cycle as
defined in Appendix I, paragraph (f), of this part, or similar trip as
approved by the Administrator.
(2) An OBD system demonstrated to fully meet the requirements in
Sec. 86.1806-10 may be used to meet the requirements of this section,
provided that the Administrator finds that a manufacturer's decision to
use the flexibility in this paragraph (a)(2) is based on good
engineering judgment.
(b) Introductory text and (b)(1)(i) [Reserved]. For guidance see
Sec. 86.005-17.
(b)(1)(ii) Diesel.
(A) If equipped, reduction catalyst deterioration or malfunction
before it results in exhaust NOX emissions exceeding the
applicable NOX FEL+0.3 g/bhp-hr. If equipped, oxidation
catalyst deterioration or malfunction before it results in exhaust NMHC
emissions exceeding 2.5 times the applicable NMHC standard. These
catalyst monitoring requirements need not be done if the manufacturer
can demonstrate that deterioration or malfunction of the system will
not result in exceedance of the threshold.
(B) If equipped, diesel particulate trap deterioration or
malfunction before it results in exhaust emissions exceeding any of the
following levels: The applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr
PM, whichever is higher; or, exhaust NMHC emissions exceeding 2.5 times
the applicable NMHC standard. Catastrophic failure of the particulate
trap must also be detected. In addition, the absence of the particulate
trap or the trapping substrate must be detected.
(b)(2) [Reserved]. For guidance see Sec. 86.005-17.
(b)(3)(i) Oxygen sensors and air-fuel ratio sensors downstream of
aftertreatment devices.
(A) Otto-cycle. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is
higher; or, the applicable NOX FEL+0.3 g/bhp-hr; or, 2.5
times the applicable NMHC standard.
(ii) Oxygen sensors and air-fuel ratio sensors upstream of
aftertreatment devices.
(A) Otto-cycle. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.02 g/bhp-hr or 0.03 g/bhp-hr PM, whichever is
higher; or, the applicable NOX FEL+0.3 g/bhp-hr; or, 2.5
times the applicable NMHC standard; or, 2.5 times the applicable CO
standard.
(iii) NOX sensors.
(A) Otto-cycle. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is
higher; or, the applicable NOX FEL+0.3 g/bhp-hr.
(b)(4) [Reserved]. For guidance see Sec. 86.005-17.
(b)(5) Other emission control systems and components.
(i) Otto-cycle. Any deterioration or malfunction occurring in an
engine system or component directly intended to control emissions,
including but not necessarily limited to, the exhaust gas recirculation
(EGR) system, if equipped, the secondary air system, if equipped, and
the fuel control system, singularly resulting in exhaust emissions
exceeding 1.5 times the applicable emission standard or FEL for NMHC,
NOX or CO. For engines equipped with a secondary air system,
a functional check, as described in Sec. 86.005-17(b)(6), may satisfy
the requirements of this paragraph (b)(5) provided the manufacturer can
demonstrate that deterioration of the flow distribution system is
unlikely. This demonstration is subject to Administrator approval and,
if the demonstration and associated functional check are approved, the
diagnostic system must indicate a malfunction when some degree of
secondary airflow is not detectable in the exhaust system during the
check. For engines equipped with positive crankcase ventilation (PCV),
monitoring of the PCV system is not necessary provided the manufacturer
can demonstrate to the Administrator's satisfaction that the PCV system
is unlikely to fail.
(ii) Diesel. Any deterioration or malfunction occurring in an
engine system or component directly intended to control emissions,
including but not necessarily limited to, the exhaust gas recirculation
(EGR) system, if equipped, and the fuel control system, singularly
resulting in exhaust emissions
[[Page 3290]]
exceeding any of the following levels: the applicable PM FEL+0.02 g/
bhp-hr or 0.03 g/bhp-hr PM, whichever is higher; or, the applicable
NOX FEL+0.3 g/bhp-hr; or, 2.5x the applicable NMHC standard;
or, 2.5x the applicable CO standard. A functional check, as described
in Sec. 86.005-17(b)(6), may satisfy the requirements of this
paragraph (b)(5) provided the manufacturer can demonstrate that a
malfunction would not cause emissions to exceed the applicable levels.
This demonstration is subject to Administrator approval. For engines
equipped with crankcase ventilation (CV), monitoring of the CV system
is not necessary provided the manufacturer can demonstrate to the
Administrator's satisfaction that the CV system is unlikely to fail.
(b)(6) [Reserved]. For guidance see Sec. 86.005-17.
(b)(7) [Reserved]. For guidance see Sec. 86.007-17.
(c) [Reserved]. For guidance see Sec. 86.005-17.
(d) MIL illumination.
(1) The MIL must illuminate and remain illuminated when any of the
conditions specified in paragraph (b) of this section are detected and
verified, or whenever the engine control enters a default or secondary
mode of operation considered abnormal for the given engine operating
conditions. The MIL must blink once per second under any period of
operation during which engine misfire is occurring and catalyst damage
is imminent. If such misfire is detected again during the following
driving cycle (i.e., operation consisting of, at a minimum, engine
start-up and engine shut-off) or the next driving cycle in which
similar conditions are encountered, the MIL must maintain a steady
illumination when the misfire is not occurring and then remain
illuminated until the MIL extinguishing criteria of this section are
satisfied. The MIL must also illuminate when the vehicle's ignition is
in the ``key-on'' position before engine starting or cranking and
extinguish after engine starting if no malfunction has previously been
detected. If a fuel system or engine misfire malfunction has previously
been detected, the MIL may be extinguished if the malfunction does not
reoccur during three subsequent sequential trips during which similar
conditions are encountered and no new malfunctions have been detected.
Similar conditions are defined as engine speed within 375 rpm, engine
load within 20 percent, and engine warm-up status equivalent to that
under which the malfunction was first detected. If any malfunction
other than a fuel system or engine misfire malfunction has been
detected, the MIL may be extinguished if the malfunction does not
reoccur during three subsequent sequential trips during which the
monitoring system responsible for illuminating the MIL functions
without detecting the malfunction, and no new malfunctions have been
detected. Upon Administrator approval, statistical MIL illumination
protocols may be employed, provided they result in comparable
timeliness in detecting a malfunction and evaluating system
performance, i.e., three to six driving cycles would be considered
acceptable.
(2) Drive cycle or driving cycle, in the context of this section
Sec. 86.010-17, the definition for drive cycle or driving cycle given
in Sec. 86.010-2 is enhanced. A drive cycle means an OBD trip that
consists of engine startup and engine shutoff and includes the period
of engine off time up to the next engine startup. For vehicles that
employ engine shutoff strategies (e.g., engine shutoff at idle), the
manufacturer may use an alternative definition for drive cycle (e.g.,
key-on followed by key-off). Any alternative definition must be based
on equivalence to engine startup and engine shutoff signaling the
beginning and ending of a single driving event for a conventional
vehicle. For applications that span 14,000 pounds GVWR, the
manufacturer may use the drive cycle definition of Sec. 86.010-18 in
lieu of the definition in this paragraph.
(e), (f), (g), and (h)(1)(i) through (h)(1)(iv) [Reserved]. For
guidance see Sec. 86.005-17.
(h)(1)(v) [Reserved]. For guidance see Sec. 86.007-17.
(h)(1)(vi) through (h)(3) [Reserved]. For guidance see Sec.
86.005-17.
(i) and (j) [Reserved]. For guidance see Sec. 86.007-17.
(k) [Reserved.]
7. Section 86.010-18 is added to Subpart A to read as follows:
Sec. 86.010-18 On-board Diagnostics for engines used in applications
greater than 14,000 pounds GVWR.
(a) General. According to the implementation schedule shown in
paragraph (o) of this section, heavy-duty engines intended for use in a
heavy-duty vehicle weighing more than 14,000 pounds GVWR must be
equipped with an on-board diagnostic (OBD) system capable of monitoring
all emission-related engine systems or components during the life of
the engine. The OBD system is required to detect all malfunctions
specified in paragraphs (g), (h), and (i) of this section although the
OBD system is not required to use a unique monitor to detect each of
those malfunctions.
(1) When the OBD system detects a malfunction, it must store a
pending, a MIL-on, or a previous-MIL-on diagnostic trouble code (DTC)
in the onboard computer's memory. A malfunction indicator light (MIL)
must also be activated as specified in paragraph (b) of this section.
(2) The OBD system must be equipped with a data link connector to
provide access to the stored DTCs as specified in paragraph (k)(2) of
this section.
(3) The OBD system cannot be programmed or otherwise designed to
deactivate based on age and/or mileage. This requirement does not alter
existing law and enforcement practice regarding a manufacturer's
liability for an engine beyond its regulatory useful life, except where
an engine has been programmed or otherwise designed so that an OBD
system deactivates based on age and/or mileage of the engine.
(4) Drive cycle or driving cycle, in the context of this section,
the definition for drive cycle or driving cycle given in Sec. 86.010-2
is enhanced. A drive cycle means an OBD trip that meets any of the
conditions of paragraphs (a)(4)(i) through (a)(4)(iv) of this section.
Further, for OBD monitors that run during engine-off conditions, the
period of engine-off time following engine shutoff and up to the next
engine start may be considered part of the drive cycle for the
conditions of paragraphs (a)(4)(i) and (a)(4)(iv) of this section. For
engines/vehicles that employ engine shutoff OBD monitoring strategies
that do not require the vehicle operator to restart the engine to
continue vehicle operation (e.g., a hybrid bus with engine shutoff at
idle), the manufacturer may use an alternative definition for drive
cycle (e.g., key-on followed by key-off). Any alternative definition
must be based on equivalence to engine startup and engine shutoff
signaling the beginning and ending of a single driving event for a
conventional vehicle. For engines that are not likely to be routinely
operated for long continuous periods of time, a manufacturer may also
request approval to use an alternative definition for drive cycle
(e.g., solely based on engine start and engine shutoff without regard
to four hours of continuous engine-on time). Administrator approval of
the alternative definition will be based on manufacturer-submitted data
and/or information demonstrating the typical usage, operating habits,
and/or driving patterns of these vehicles.
(i) Begins with engine start and ends with engine shutoff;
[[Page 3291]]
(ii) Begins with engine start and ends after four hours of
continuous engine-on operation;
(iii) Begins at the end of the previous four hours of continuous
engine-on operation and ends after four hours of continuous engine-on
operation; or
(iv) Begins at the end of the previous four hours of continuous
engine-on operation and ends with engine shutoff.
(b) Malfunction indicator light (MIL) and Diagnostic Trouble Codes
(DTC). The OBD system must incorporate a malfunction indicator light
(MIL) or equivalent and must store specific types of diagnostic trouble
codes (DTC).
(1) MIL specifications.
(i) [Reserved.]
(ii) The OBD system must activate the MIL when the ignition is in
the key-on/engine-off position before engine cranking to indicate that
the MIL is functional. The MIL shall be activated continuously during
this functional check for a minimum of 5 seconds. During this MIL key-
on functional check, the data stream value (see paragraph (k)(4)(ii) of
this section) for MIL status must indicate ``commanded off'' unless the
OBD system has detected a malfunction and has stored a MIL-on DTC. This
MIL key-on functional check is not required during vehicle operation in
the key-on/engine-off position subsequent to the initial engine
cranking of an ignition cycle (e.g., due to an engine stall or other
non-commanded engine shutoff).
(iii) As an option, the MIL may be used to indicate readiness
status (see paragraph (k)(4)(i) of this section) in a standardized
format in the key-on/engine-off position.
(iv) A manufacturer may also use the MIL to indicate which, if any,
DTCs are currently stored (e.g., to ``blink'' the stored DTCs). Such
use must not activate unintentionally during routine driver operation.
(v) [Reserved.]
(2) MIL activation and DTC storage protocol.
(i) Within 10 seconds of detecting a potential malfunction, the OBD
system must store a pending DTC that identifies the potential
malfunction.
(ii) If the potential malfunction is again detected before the end
of the next drive cycle during which monitoring occurs (i.e., the
potential malfunction has been confirmed as a malfunction), then within
10 seconds of such detection the OBD system must activate the MIL
continuously and store a MIL-on DTC. If the potential malfunction is
not detected before the end of the next drive cycle during which
monitoring occurs (i.e., there is no indication of the malfunction at
any time during the drive cycle), the corresponding pending DTC should
be erased at the end of the drive cycle. Similarly, if a malfunction is
detected for the first time and confirmed on a given drive cycle
without need for further evaluation, then within 10 seconds of such
detection the OBD system must activate the MIL continuously and store a
MIL-on DTC.
(iii) A manufacturer may request Administrator approval to employ
alternative statistical MIL activation and DTC storage protocols to
those specified in paragraphs (b)(2)(i) and (b)(2)(ii) of this section.
Approval will depend upon the manufacturer providing data and/or
engineering evaluations that demonstrate that the alternative protocols
can evaluate system performance and detect malfunctions in a manner
that is equally effective and timely. Strategies requiring on average
more than six drive cycles for MIL activation will not be accepted.
(iv) The OBD system must store a ``freeze frame'' of the operating
conditions (as defined in paragraph (k)(4)(iii) of this section)
present upon detecting a malfunction or a potential malfunction. In the
event that a pending DTC has matured to a MIL-on DTC, the manufacturer
shall either retain the currently stored freeze frame conditions or
replace the stored freeze frame with freeze frame conditions regarding
the MIL-on DTC. Any freeze frame stored in conjunction with any pending
DTC or MIL-on DTC should be erased upon erasure of the corresponding
DTC.
(v) If the engine enters a limp-home mode of operation that can
affect emissions or the performance of the OBD system, or in the event
of a malfunction of an onboard computer(s) itself that can affect the
performance of the OBD system, the OBD system must activate the MIL and
store a MIL-on DTC within 10 seconds to inform the vehicle operator. If
the limp-home mode of operation is recoverable (i.e., operation
automatically returns to normal at the beginning of the following
ignition cycle), the OBD system may wait to activate the MIL and store
the MIL-on DTC if the limp-home mode of operation is again entered
before the end of the next ignition cycle rather than activating the
MIL within 10 seconds on the first drive cycle during which the limp-
home mode of operation is entered.
(vi) Before the end of an ignition cycle, the OBD system must store
a permanent DTC(s) that corresponds to any stored MIL-on DTC(s).
(3) MIL deactivation and DTC erasure protocol.
(i) Deactivating the MIL. Except as otherwise provided for in
paragraph (g)(6)(iv)(B) of this section for empty reductant tanks, and
paragraphs (h)(1)(iv)(F), (h)(2)(viii), and (h)(7)(iv)(B) of this
section for gasoline fuel system, misfire, and evaporative system
malfunctions, once the MIL has been activated, it may be deactivated
after three subsequent sequential drive cycles during which the
monitoring system responsible for activating the MIL functions and the
previously detected malfunction is no longer present and provided no
other malfunction has been detected that would independently activate
the MIL according to the requirements outlined in paragraph (b)(2) of
this section.
(ii) Erasing a MIL-on DTC. The OBD system may erase a MIL-on DTC if
the identified malfunction has not again been detected in at least 40
engine warm up cycles and the MIL is presently not activated for that
malfunction. The OBD system may also erase a MIL-on DTC upon
deactivating the MIL according to paragraph (b)(3)(i) of this section
provided a previous-MIL-on DTC is stored upon erasure of the MIL-on
DTC. The OBD system may erase a previous-MIL-on DTC if the identified
malfunction has not again been detected in at least 40 engine warm up
cycles and the MIL is presently not activated for that malfunction.
(iii) Erasing a permanent DTC. The OBD system can erase a permanent
DTC only if either of the following conditions occur:
(A) The OBD system itself determines that the malfunction that
caused the corresponding MIL-on DTC to be stored is no longer present
and is not commanding activation of the MIL, concurrent with the
requirements of paragraph (b)(3)(i) of this section.
(B) Subsequent to erasing the DTC information from the on-board
computer (i.e., through the use of a scan tool or a battery
disconnect), the OBD monitor for the malfunction that caused the
permanent DTC to be stored has executed the minimum number of
monitoring events necessary for MIL activation and has determined that
the malfunction is no longer present.
(4) Exceptions to MIL and DTC requirements.
(i) If a limp-home mode of operation causes an overt indication
(e.g., activation of a red engine shut-down warning light) such that
the driver is certain to respond and have the problem corrected, a
manufacturer may choose not to activate the MIL as required by
paragraph (b)(2)(v) of this section. Additionally, if an auxiliary
emission control device has been properly
[[Page 3292]]
activated as approved by the Administrator, a manufacturer may choose
not to activate the MIL.
(ii) For gasoline engines, a manufacturer may choose to meet the
MIL and DTC requirements in Sec. 86.010-17 in lieu of meeting the
requirements of paragraph (b) of Sec. 86.010-18.
(a) Monitoring conditions. The OBD system must monitor and detect
the malfunctions specified in paragraphs (g), (h), and (i) of this
section under the following general monitoring conditions. The more
specific monitoring conditions of paragraph (d) of this section are
sometimes required according to the provisions of paragraphs (g), (h),
and (i) of this section.
(1) As specifically provided for in paragraphs (g), (h), and (i) of
this section, the monitoring conditions for detecting malfunctions must
be technically necessary to ensure robust detection of malfunctions
(e.g., avoid false passes and false indications of malfunctions);
designed to ensure monitoring will occur under conditions that may
reasonably be expected to be encountered in normal vehicle operation
and normal vehicle use; and, designed to ensure monitoring will occur
during the FTP transient test cycle contained in Appendix I paragraph
(f), of this part, or similar drive cycle as approved by the
Administrator.
(2) Monitoring must occur at least once per drive cycle in which
the monitoring conditions are met.
(3) Manufacturers may request approval to define monitoring
conditions that are not encountered during the FTP cycle as required in
paragraph (c)(1) of this section. In evaluating the manufacturer's
request, the Administrator will consider the degree to which the
requirement to run during the FTP transient cycle restricts monitoring
during in-use operation, the technical necessity for defining
monitoring conditions that are not encountered during the FTP cycle,
data and/or an engineering evaluation submitted by the manufacturer
that demonstrate that the component/system does not normally function
during the FTP, whether monitoring is otherwise not feasible during the
FTP cycle, and/or the ability of the manufacturer to demonstrate that
the monitoring conditions satisfy the minimum acceptable in-use monitor
performance ratio requirement as defined in paragraph (d) of this
section.
(d) In-use performance tracking. As specifically required in
paragraphs (g), (h), and (i) of this section, the OBD system must
monitor and detect the malfunctions specified in paragraphs (g), (h),
and (i) of this section according to the criteria of this paragraph
(d). The OBD system is not required to track and report in-use
performance for monitors other than those specifically identified in
paragraph (d)(1) of this section.
(1) The manufacturer must implement software algorithms in the OBD
system to individually track and report the in-use performance of the
following monitors, if equipped, in the standardized format specified
in paragraph (e) of this section: NMHC converting catalyst (paragraph
(g)(5) of this section); NOX converting catalyst (paragraph
(g)(6) of this section); gasoline catalyst (paragraph (h)(6) of this
section); exhaust gas sensor (paragraph (g)(9) or (h)(8) of this
section); evaporative system (paragraph (h)(7) of this section); EGR
system (paragraph (g)(3) or (h)(3) of this section); VVT system
(paragraph (g)(10) or (h)(9) of this section); secondary air system
(paragraph (h)(5) of this section); DPF system (paragraph (g)(8) of
this section); boost pressure control system (paragraph (g)(4) of this
section); and, NOX adsorber system (paragraph (g)(7) of this
section).
(i) The manufacturer shall not use the calculated ratio specified
in paragraph (d)(2) of this section or any other indication of monitor
frequency as a monitoring condition for a monitor (e.g., using a low
ratio to enable more frequent monitoring through diagnostic executive
priority or modification of other monitoring conditions, or using a
high ratio to enable less frequent monitoring).
(ii) [Reserved.]
(2) In-use performance ratio definition. For monitors required to
meet the requirements of paragraph (d) of this section, the performance
ratio must be calculated in accordance with the specifications of this
paragraph (d)(2).
(i) The numerator of the performance ratio is defined as the number
of times a vehicle has been operated such that all monitoring
conditions have been encountered that are necessary for the specific
monitor to detect a malfunction.
(ii) The denominator is defined as the number of times a vehicle
has been operated in accordance with the provisions of paragraph (d)(4)
of this section.
(iii) The performance ratio is defined as the numerator divided by
the denominator.
(3) Specifications for incrementing the numerator.
(i) Except as provided for in paragraph (d)(3)(v) of this paragraph
(d)(3), the numerator, when incremented, must be incremented by an
integer of one. The numerator shall not be incremented more than once
per drive cycle.
(ii) The numerator for a specific monitor must be incremented
within 10 seconds if and only if the following criteria are satisfied
on a single drive cycle:
(A) Every monitoring condition has been satisfied that is necessary
for the specific monitor to detect a malfunction and store a pending
DTC, including applicable enable criteria, presence or absence of
related DTCs, sufficient length of monitoring time, and diagnostic
executive priority assignments (e.g., diagnostic ``A'' must execute
prior to diagnostic ``B''). For the purpose of incrementing the
numerator, satisfying all the monitoring conditions necessary for a
monitor to determine that the monitor is not malfunctioning shall not,
by itself, be sufficient to meet this criteria.
(B) For monitors that require multiple stages or events in a single
drive cycle to detect a malfunction, every monitoring condition
necessary for all events to complete must be satisfied.
(C) For monitors that require intrusive operation of components to
detect a malfunction, a manufacturer must request approval of the
strategy used to determine that, had a malfunction been present, the
monitor would have detected the malfunction. Administrator approval of
the request will be based on the equivalence of the strategy to actual
intrusive operation and the ability of the strategy to determine
accurately if every monitoring condition was satisfied that was
necessary for the intrusive event to occur.
(D) For the secondary air system monitor, the criteria in
paragraphs (d)(3)(ii)(A) through (d)(3)(ii)(C) of this section are
satisfied during normal operation of the secondary air system.
Monitoring during intrusive operation of the secondary air system later
in the same drive cycle for the sole purpose of monitoring shall not,
by itself, be sufficient to meet these criteria.
(iii) For monitors that can generate results in a ``gray zone'' or
``non-detection zone'' (i.e., monitor results that indicate neither a
properly operating system nor a malfunctioning system) or in a ``non-
decision zone'' (e.g., monitors that increment and decrement counters
until a pass or fail threshold is reached), the numerator, in general,
shall not be incremented when the monitor indicates a result in the
``non-detection zone'' or prior to the monitor reaching a complete
decision. When necessary, the Administrator will consider data and/or
engineering analyses submitted by the manufacturer
[[Page 3293]]
demonstrating the expected frequency of results in the ``non-detection
zone'' and the ability of the monitor to determine accurately, had an
actual malfunction been present, whether or not the monitor would have
detected a malfunction instead of a result in the ``non-detection
zone.''
(iv) For monitors that run or complete their evaluation with the
engine off, the numerator must be incremented either within 10 seconds
of the monitor completing its evaluation in the engine off state, or
during the first 10 seconds of engine start on the subsequent drive
cycle.
(v) Manufacturers that use alternative statistical MIL activation
protocols as allowed in paragraph (b)(2)(iii) of this section for any
of the monitors requiring a numerator, are required to increment the
numerator(s) appropriately. The manufacturer may be required to provide
supporting data and/or engineering analyses demonstrating both the
equivalence of their incrementing approach to the incrementing
specified in this paragraph (d)(3) for monitors using the standard MIL
activation protocol.
(4) Specifications for incrementing the denominator.
(i) The denominator, when incremented, must be incremented by an
integer of one. The denominator shall not be incremented more than once
per drive cycle.
(ii) The denominator for each monitor must be incremented within 10
seconds if and only if the following criteria are satisfied on a single
drive cycle:
(A) Cumulative time since the start of the drive cycle is greater
than or equal to 600 seconds while at an elevation of less than 8,000
feet (2,400 meters) above sea level and at an ambient temperature of
greater than or equal to 20 degrees Fahrenheit (-7 C);
(B) Cumulative gasoline engine operation at or above 25 miles per
hour or diesel engine operation at or above 15% calculated load, either
of which occurs for greater than or equal to 300 seconds while at an
elevation of less than 8,000 feet (2,400 meters) above sea level and at
an ambient temperature of greater than or equal to 20 degrees
Fahrenheit (-7 C); and
(C) Continuous vehicle operation at idle (e.g., accelerator pedal
released by driver and vehicle speed less than or equal to one mile per
hour) for greater than or equal to 30 seconds while at an elevation of
less than 8,000 feet (2,400 meters) above sea level and at an ambient
temperature of greater than or equal to 20 degrees Fahrenheit (-7 C).
(iii) In addition to the requirements of paragraph (d)(4)(ii) of
this section, the evaporative system monitor denominator(s) may be
incremented if and only if:
(A) Cumulative time since the start of the drive cycle is greater
than or equal to 600 seconds while at an ambient temperature of greater
than or equal to 40 degrees Fahrenheit (4 C) but less than or equal to
95 degrees Fahrenheit (35 C); and,
(B) Engine cold start occurs with the engine coolant temperature
greater than or equal to 40 degrees Fahrenheit (4 C) but less than or
equal to 95 degrees Fahrenheit (35 C) and less than or equal to 12
degrees Fahrenheit (7 C) higher than the ambient temperature.
(iv) In addition to the requirements of paragraph (d)(4)(ii) of
this section, the denominator(s) for the following monitors may be
incremented if and only if the component or strategy is commanded
``on'' for a time greater than or equal to 10 seconds. For purposes of
determining this commanded ``on'' time, the OBD system shall not
include time during intrusive operation of any of the components or
strategies that occurs later in the same drive cycle for the sole
purpose of monitoring.
(A) Secondary air system (paragraph (h)(5) of this section).
(B) Cold start emission reduction strategy (paragraph (h)(4) of
this section).
(C) Components or systems that operate only at engine start-up
(e.g., glow plugs, intake air heaters) and are subject to monitoring
under ``other emission control systems'' (paragraph (i)(4) of this
section) or comprehensive component output components (paragraph
(i)(3)(iii) of this section).
(v) In addition to the requirements of paragraph (d)(4)(ii) of this
section, the denominator(s) for the following monitors of output
components (except those operated only at engine start-up and subject
to the requirements of paragraph (d)(4)(iv) of this section, may be
incremented if and only if the component is commanded to function
(e.g., commanded ``on'', ``opened'', ``closed'', ``locked'') on two or
more occasions during the drive cycle or for a time greater than or
equal to 10 seconds, whichever occurs first:
(A) Variable valve timing and/or control system (paragraph (g)(10)
or (h)(9) of this section).
(B) ``Other emission control systems'' (paragraph (i)(4) of this
section).
(C) Comprehensive component output component (paragraph (i)(3) of
this section) (e.g., turbocharger waste-gates, variable length manifold
runners).
(vi) For monitors of the following components, the manufacturer may
use alternative or additional criteria for incrementing the denominator
to that set forth in paragraph (d)(4)(ii) of this section. To do so,
the alternative criteria must be based on equivalence to the criteria
of paragraph (d)(4)(ii) of this section in measuring the frequency of
monitor operation relative to the amount of engine operation:
(A) Engine cooling system input components (paragraph (i)(1) of
this section).
(B) ``Other emission control systems'' (paragraph (i)(4) of this
section).
(C) Comprehensive component input components that require extended
monitoring evaluation (paragraph (i)(3) of this section) (e.g., stuck
fuel level sensor rationality).
(vii) For monitors of the following components or other emission
controls that experience infrequent regeneration events, the
manufacturer may use alternative or additional criteria for
incrementing the denominator to that set forth in paragraph (d)(4)(ii)
of this section. To do so, the alternative criteria must be based on
equivalence to the criteria of paragraph (d)(4)(ii) of this section in
measuring the frequency of monitor operation relative to the amount of
engine operation:
(A) Oxidation catalyst (paragraph (g)(5) of this section).
(B) DPF (paragraph (g)(8) of this section).
(viii) For hybrids that employ alternative engine start hardware or
strategies (e.g., integrated starter and generators), or alternative
fuel vehicles (e.g. dedicated, bi-fuel, or dual-fuel applications), the
manufacturer may use alternative criteria for incrementing the
denominator to that set forth in paragraph (d)(4)(ii) of this section.
In general, the Administrator will not approve alternative criteria for
those hybrids that employ engine shut off only at or near idle and/or
vehicle stop conditions. To use alternative criteria, the alternative
criteria must be based on the equivalence to the criteria of paragraph
(d)(4)(ii) of this section in measuring the amount of vehicle operation
relative to the measure of conventional vehicle operation.
(5) Disablement of numerators and denominators.
(i) Within 10 seconds of detecting a malfunction (i.e. a pending or
a MIL-on DTC has been stored) that disables a monitor for which the
monitoring conditions in paragraph (d) of this section must be met, the
OBD system must stop incrementing the numerator and denominator for any
monitor that may be disabled as a consequence of the detected
malfunction. Within 10 seconds of the time at which the malfunction is
no longer being detected
[[Page 3294]]
(e.g., the pending DTC is erased through OBD system self-clearing or
through a scan tool command), incrementing of all applicable numerators
and denominators must resume.
(ii) Within 10 seconds of the start of a power take-off unit (e.g.,
dump bed, snow plow blade, or aerial bucket, etc.) that disables a
monitor for which the monitoring conditions in paragraph (d) of this
section must be met, the OBD system must stop incrementing the
numerator and denominator for any monitor that may be disabled as a
consequence of power take-off operation. Within 10 seconds of the time
at which the power take-off operation ends, incrementing of all
applicable numerators and denominators must resume.
(iii) Within 10 seconds of detecting a malfunction (i.e., a pending
or a MIL-on DTC has been stored) of any component used to determine if
the criteria of paragraphs (d)(4)(ii) and (d)(4)(iii) of this section
are satisfied, the OBD system must stop incrementing all applicable
numerators and denominators. Within 10 seconds of the time at which the
malfunction is no longer being detected (e.g., the pending DTC is
erased through OBD system self-clearing or through a scan tool
command), incrementing of all applicable numerators and denominators
must resume.
(e) Standardized tracking and reporting of in-use monitor
performance.
(1) General. For monitors required to track and report in-use
monitor performance according to paragraph (d) of this section, the
performance data must be tracked and reported in accordance with the
specifications in paragraphs (d)(2), (e), and (k)(5) of this section.
The OBD system must separately report an in-use monitor performance
numerator and denominator for each of the following components:
(i) For diesel engines, NMHC catalyst bank 1, NMHC catalyst bank 2,
NOX catalyst bank 1, NOX catalyst bank 2, exhaust
gas sensor bank 1, exhaust gas sensor bank 2, EGR/VVT system, DPF,
boost pressure control system, and NOX adsorber. The OBD
system must also report a general denominator and an ignition cycle
counter in the standardized format specified in paragraphs (e)(5),
(e)(6), and (k)(5) of this section.
(ii) For gasoline engines, catalyst bank 1, catalyst bank 2,
exhaust gas sensor bank 1, exhaust gas sensor bank 2, evaporative leak
detection system, EGR/VVT system, and secondary air system. The OBD
system must also report a general denominator and an ignition cycle
counter in the standardized format specified in paragraphs (e)(5),
(e)(6), and (k)(5) of this section.
(iii) For specific components or systems that have multiple
monitors that are required to be reported under paragraphs (g) and (h)
of this section (e.g., exhaust gas sensor bank 1 may have multiple
monitors for sensor response or other sensor characteristics), the OBD
system must separately track numerators and denominators for each of
the specific monitors and report only the corresponding numerator and
denominator for the specific monitor that has the lowest numerical
ratio. If two or more specific monitors have identical ratios, the
corresponding numerator and denominator for the specific monitor that
has the highest denominator must be reported for the specific
component.
(2) Numerator.
(i) The OBD system must report a separate numerator for each of the
applicable components listed in paragraph (e)(1) of this section.
(ii) The numerator(s) must be reported in accordance with the
specifications in paragraph (k)(5)(ii) of this section.
(3) Denominator.
(i) The OBD system must report a separate denominator for each of
the applicable components listed in paragraph (e)(1) of this section.
(ii) The denominator(s) must be reported in accordance with the
specifications in paragraph (k)(5)(ii) of this section.
(4) Monitor performance ratio. For purposes of determining which
corresponding numerator and denominator to report as required in
paragraph (e)(1)(iii) of this section, the ratio must be calculated in
accordance with the specifications in paragraph (k)(5)(iii) of this
section.
(5) Ignition cycle counter.
(i) The ignition cycle counter is defined as a counter that
indicates the number of ignition cycles a vehicle has experienced
according to the specifications of paragraph (e)(5)(ii)(B) of this
section. The ignition cycle counter must be reported in accordance with
the specifications in paragraph (k)(5)(ii) of this section.
(ii) The ignition cycle counter must be incremented as follows:
(A) The ignition cycle counter, when incremented, must be
incremented by an integer of one. The ignition cycle counter shall not
be incremented more than once per ignition cycle.
(B) The ignition cycle counter must be incremented within 10
seconds if and only if the engine exceeds an engine speed of 50 to 150
rpm below the normal, warmed-up idle speed (as determined in the drive
position for engines paired with an automatic transmission) for at
least two seconds plus or minus one second.
(iii) Within 10 seconds of detecting a malfunction (i.e., a pending
or a MIL-on DTC has been stored) of any component used to determine if
the criteria in paragraph (e)(5)(ii)(B) of this section are satisfied
(i.e., engine speed or time of operation), the OBD system must stop
incrementing the ignition cycle counter. Incrementing of the ignition
cycle counter shall not be stopped for any other condition. Within 10
seconds of the time at which the malfunction is no longer being
detected (e.g., the pending DTC is erased through OBD system self-
clearing or through a scan tool command), incrementing of the ignition
cycle counter must resume.
(6) General denominator.
(i) The general denominator is defined as a measure of the number
of times an engine has been operated according to the specifications of
paragraph (e)(6)(ii)(B) of this section. The general denominator must
be reported in accordance with the specifications in paragraph
(k)(5)(ii) of this section.
(ii) The general denominator must be incremented as follows:
(A) The general denominator, when incremented, must be incremented
by an integer of one. The general denominator shall not be incremented
more than once per drive cycle.
(B) The general denominator must be incremented within 10 seconds
if and only if the criteria identified in paragraph (d)(4)(ii) of this
section are satisfied on a single drive cycle.
(C) Within 10 seconds of detecting a malfunction (i.e., a pending
or a MIL-on DTC has been stored) of any component used to determine if
the criteria in paragraph (d)(4)(ii) of this section are satisfied
(i.e., vehicle speed/load, ambient temperature, elevation, idle
operation, or time of operation), the OBD system must stop incrementing
the general denominator. Incrementing of the general denominator shall
not be stopped for any other condition (e.g., the disablement criteria
in paragraphs (d)(5)(i) and (d)(5)(ii) of this section shall not
disable the general denominator). Within 10 seconds of the time at
which the malfunction is no longer being detected (e.g., the pending
DTC is erased through OBD system self-clearing or through a scan tool
command), incrementing of the general denominator must resume.
(f) Malfunction criteria determination.
(1) In determining the malfunction criteria for the diesel engine
monitors required under paragraphs (g) and (i) of
[[Page 3295]]
this section that are required to indicate a malfunction before
emissions exceed an emission threshold based on any applicable
standard, the manufacturer must:
(i) Use the emission test cycle and standard (i.e., the transient
FTP or the supplemental emissions test (SET)) determined by the
manufacturer to be more stringent (i.e., to result in higher emissions
with the same level of monitored component malfunction). The
manufacturer must use data and/or engineering analysis to determine the
test cycle and standard that is more stringent.
(ii) Identify in the certification documentation required under
paragraph (m) of this section, the test cycle and standard determined
by the manufacturer to be the most stringent for each applicable
monitor.
(iii) If the Administrator reasonably believes that a manufacturer
has determined incorrectly the test cycle and standard that is most
stringent, the manufacturer must be able to provide emission data and/
or engineering analysis supporting their choice of test cycle and
standard.
(2) On engines equipped with emission controls that experience
infrequent regeneration events, a manufacturer must adjust the emission
test results that are used to determine the malfunction criteria for
monitors that are required to indicate a malfunction before emissions
exceed a certain emission threshold. For each such monitor, the
manufacturer must adjust the emission result as done in accordance with
the provisions of section 86.004-28(i) with the component for which the
malfunction criteria are being established having been deteriorated to
the malfunction threshold. The adjusted emission value must be used for
purposes of determining whether or not the applicable emission
threshold is exceeded.
(i) For purposes of this paragraph (f)(2) of this section,
regeneration means an event, by design, during which emissions levels
change while the emission control performance is being restored.
(ii) For purposes of this paragraph (f)(2) of this section,
infrequent means having an expected frequency of less than once per
transient FTP cycle.
(3) For gasoline engines, rather than meeting the malfunction
criteria specified under paragraphs (h) and (i) of this section, the
manufacturer may request approval to use an OBD system certified to the
requirements of Sec. 86.010-17. To do so, the manufacturer must
demonstrate use of good engineering judgment in determining equivalent
malfunction detection criteria to those required in this section.
(g) OBD monitoring requirements for diesel-fueled/compression-
ignition engines. The following table shows the thresholds at which
point certain components or systems, as specified in this paragraph
(g), are considered malfunctioning.
Table 1.--OBD Emissions Thresholds for Diesel-Fueled/Compression-Ignition Engines Meant for Placement in Applications Greater Than 14,000 Pounds GVWR (g/
bhp-hr)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Component Sec. 86.010-18 reference NMHC CO NOX PM
--------------------------------------------------------------------------------------------------------------------------------------------------------
NMHC catalyst system................ (g)(5)............................ 2.5x................. .................... .................... ...........
NOX aftertreatment system........... (g)(6), (g)(7).................... ..................... .................... +0.3................ ...........
Diesel particulate filter (DPF) (g)(8)............................ 2.5x................. .................... .................... 0.05/+0.04
system.
Air-fuel ratio sensors upstream of (g)(9)............................ 2.5x................. 2.5x................ +0.3................ 0.03/+0.02
aftertreatment devices.
Air-fuel ratio sensors downstream of (g)(9)............................ 2.5x................. .................... +0.3................ 0.05/+0.04
aftertreatment devices.
NOX sensors......................... (g)(9)............................ ..................... .................... +0.3................ 0.05/+0.04
``Other monitors'' with emissions (g)(1), (g)(3), (g)(4), (g)(10)... 2.5x................. 2.5x................ +0.3................ 0.03/+0.02
thresholds.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: FEL=Family Emissions Limit; 2.5x std means a multiple of 2.5 times the applicable emissions standard; +0.3 means the standard or FEL plus 0.3;
0.05/+0.04 means an absolute level of 0.05 or an additive level of the standard or FEL plus 0.04, whilchever level is higher; these emissions
thresholds apply to the monitoring requirements of paragraph (g) of this section 86.010-18.
(1) Fuel system monitoring.
(i) General. The OBD system must monitor the fuel delivery system
to verify that it is functioning properly. The individual electronic
components (e.g., actuators, valves, sensors, pumps) that are used in
the fuel system and are not specifically addressed in this paragraph
(g)(1) must be monitored in accordance with the requirements of
paragraph (i)(3) of this section.
(ii) Fuel system malfunction criteria.
(A) Fuel system pressure control. The OBD system must monitor the
fuel system's ability to control to the desired fuel pressure. This
monitoring must be done continuously unless new hardware has to be
added, in which case the monitoring must be done at least once per
drive cycle. The OBD system must detect a malfunction of the fuel
system's pressure control system when the pressure control system is
unable to maintain an engine's emissions at or below the emissions
thresholds for ``other monitors'' as shown in Table 1 of this paragraph
(g). For engines in which no failure or deterioration of the fuel
system pressure control could result in an engine's emissions exceeding
the applicable emissions thresholds, the OBD system must detect a
malfunction when the system has reached its control limits such that
the commanded fuel system pressure cannot be delivered.
(B) Fuel system injection quantity. The OBD system must detect a
malfunction of the fuel injection system when the system is unable to
deliver the commanded quantity of fuel necessary to maintain an
engine's emissions at or below the emissions thresholds for ``other
monitors'' as shown in Table 1 of this paragraph (g). For engines in
which no failure or deterioration of the fuel injection quantity could
result in an engine's emissions exceeding the applicable emissions
thresholds, the OBD system must detect a malfunction when the system
has reached its control limits such that the commanded fuel quantity
cannot be delivered.
(C) Fuel system injection timing. The OBD system must detect a
malfunction of the fuel injection system when the system is unable to
deliver fuel at the proper crank angle/timing (e.g., injection timing
too advanced or too retarded) necessary to maintain an engine's
emissions at or below the emissions thresholds for ``other monitors''
as shown in Table 1 of this paragraph (g). For engines in which no
failure or deterioration of the fuel injection timing could result in
an engine's emissions exceeding the applicable emissions thresholds,
the OBD system must detect a malfunction when the system has reached
its control limits such that the commanded fuel injection timing cannot
be achieved.
[[Page 3296]]
(D) Fuel system feedback control. See paragraph (i)(6) of this
section.
(iii) Fuel system monitoring conditions.
(A) The OBD system must monitor continuously for malfunctions
identified in paragraphs (g)(1)(ii)(A) and (g)(1)(ii)(D) of this
section.
(B) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraphs (g)(1)(ii)(B) and (g)(1)(ii)(C)
in accordance with paragraphs (c) and (d) of this section.
(iv) Fuel system MIL activation and DTC storage. The MIL must
activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(2) Engine misfire monitoring.
(i) General. The OBD system must monitor the engine for misfire
causing excess emissions.
(ii) Engine misfire malfunction criteria. The OBD system must be
capable of detecting misfire occurring in one or more cylinders. To the
extent possible without adding hardware for this specific purpose, the
OBD system must also identify the specific misfiring cylinder. If more
than one cylinder is misfiring continuously, a separate DTC must be
stored indicating that multiple cylinders are misfiring. When
identifying multiple cylinder misfire, the OBD system is not required
to identify individually through separate DTCs each of the continuously
misfiring cylinders.
(iii) Engine misfire monitoring conditions.
(A) The OBD system must monitor for engine misfire during engine
idle conditions at least once per drive cycle in which the monitoring
conditions for misfire are met. The manufacturer must be able to
demonstrate via engineering analysis and/or data that the self-defined
monitoring conditions: Are technically necessary to ensure robust
detection of malfunctions (e.g., avoid false passes and false detection
of malfunctions); require no more than 1000 cumulative engine
revolutions; and, do not require any single continuous idle operation
of more than 15 seconds to make a determination that a malfunction is
present (e.g., a decision can be made with data gathered during several
idle operations of 15 seconds or less); or, satisfy the requirements of
paragraph (c) of this section with alternative engine operating
conditions.
(B) Manufacturers may employ alternative monitoring conditions
(e.g., off-idle) provided the manufacturer is able to demonstrate that
the alternative monitoring ensure equivalent robust detection of
malfunctions and equivalent timeliness in detection of malfunctions.
(iv) Engine misfire MIL activation and DTC storage. The MIL must
activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(3) EGR system monitoring.
(i) General. The OBD system must monitor the EGR system on engines
so equipped for low flow rate, high flow rate, and slow response
malfunctions. For engines equipped with EGR coolers (e.g., heat
exchangers), the OBD system must monitor the cooler for insufficient
cooling malfunctions. The individual electronic components (e.g.,
actuators, valves, sensors) that are used in the EGR system must be
monitored in accordance with the comprehensive component requirements
in paragraph (i)(3) of this section.
(ii) EGR system malfunction criteria.
(A) EGR low flow. The OBD system must detect a malfunction of the
EGR system prior to a decrease from the manufacturer's specified EGR
flow rate that would cause an engine's emissions to exceed the
emissions thresholds for ``other monitors'' as shown in Table 1 of this
paragraph (g). For engines in which no failure or deterioration of the
EGR system that causes a decrease in flow could result in an engine's
emissions exceeding the applicable emissions thresholds, the OBD system
must detect a malfunction when the system has reached its control
limits such that it cannot increase EGR flow to achieve the commanded
flow rate.
(B) EGR high flow. The OBD system must detect a malfunction of the
EGR system, including a leaking EGR valve (i.e., exhaust gas flowing
through the valve when the valve is commanded closed) prior to an
increase from the manufacturer's specified EGR flow rate that would
cause an engine's emissions to exceed the emissions thresholds for
``other monitors'' as shown in Table 1 of this paragraph (g). For
engines in which no failure or deterioration of the EGR system that
causes an increase in flow could result in an engine's emissions
exceeding the applicable emissions thresholds, the OBD system must
detect a malfunction when the system has reached its control limits
such that it cannot reduce EGR flow to achieve the commanded flow rate.
(C) EGR slow response. The OBD system must detect a malfunction of
the EGR system prior to any failure or deterioration in the capability
of the EGR system to achieve the commanded flow rate within a
manufacturer-specified time that would cause an engine's emissions to
exceed the emissions thresholds for ``other monitors'' as shown in
Table 1 of this paragraph (g). The OBD system must monitor both the
capability of the EGR system to respond to a commanded increase in flow
and the capability of the EGR system to respond to a commanded decrease
in flow.
(D) EGR system feedback control. See paragraph (i)(6) of this
section.
(E) EGR cooler performance. The OBD system must detect a
malfunction of the EGR cooler prior to a reduction from the
manufacturer's specified cooling performance that would cause an
engine's emissions to exceed the emissions thresholds for ``other
monitors'' as shown in Table 1 of this paragraph (g). For engines in
which no failure or deterioration of the EGR cooler could result in an
engine's emissions exceeding the applicable emissions thresholds, the
OBD system must detect a malfunction when the system has no detectable
amount of EGR cooling.
(iii) EGR system monitoring conditions.
(A) The OBD system must monitor continuously for malfunctions
identified in paragraphs (g)(3)(ii)(A), (g)(3)(ii)(B), and
(g)(3)(ii)(D) of this section.
(B) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraph (g)(3)(ii)(C) in accordance with
paragraphs (c) and (d) of this section, with the exception that
monitoring must occur every time the monitoring conditions are met
during the drive cycle rather than once per drive cycle as required in
paragraph (c)(2) of this section. For purposes of tracking and
reporting as required in paragraph (d)(1) of this section, all monitors
used to detect malfunctions identified in paragraph (g)(3)(ii)(C) of
this section must be tracked separately but reported as a single set of
values as specified in paragraph (e)(1)(iii) of this section.
(C) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraph (g)(3)(ii)(E) of this section in
accordance with paragraphs (c) and (d) of this section. For purposes of
tracking and reporting as required in paragraph (d)(1) of this section,
all monitors used to detect malfunctions identified in paragraph
(g)(3)(ii)(E) of this section must be tracked separately but reported
as a single set of values as specified in paragraph (e)(1)(iii) of this
section.
(D) The manufacturer may request Administrator approval to disable
temporarily the EGR system monitor(s) under specific conditions (e.g.,
when freezing may affect performance of the system) provided the
manufacturer is
[[Page 3297]]
able to demonstrate via data or engineering analysis that a reliable
monitor cannot be run when these conditions exist.
(iv) EGR system MIL activation and DTC storage. The MIL must
activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(4) Turbo boost control system monitoring.
(i) General. The OBD system must monitor the boost pressure control
system (e.g., turbocharger) on engines so equipped for under and over
boost malfunctions. For engines equipped with variable geometry
turbochargers (VGT), the OBD system must monitor the VGT system for
slow response malfunctions. For engines equipped with charge air cooler
systems, the OBD system must monitor the charge air cooler system for
cooling system performance malfunctions. The individual electronic
components (e.g., actuators, valves, sensors) that are used in the
boost pressure control system must be monitored in accordance with the
comprehensive component requirements in paragraph (i)(3) of this
section.
(ii) Turbo boost control system malfunction criteria.
(A) Turbo underboost. The OBD system must detect a malfunction of
the boost pressure control system prior to a decrease from the
manufacturer's commanded boost pressure that would cause an engine's
emissions to exceed the emissions thresholds for ``other monitors'' as
shown in Table 1 of this paragraph (g). For engines in which no failure
or deterioration of the boost pressure control system that causes a
decrease in boost could result in an engine's emissions exceeding the
applicable emissions thresholds, the OBD system must detect a
malfunction when the system has reached its control limits such that it
cannot increase boost to achieve the commanded boost pressure.
(B) Turbo overboost. The OBD system must detect a malfunction of
the boost pressure control system prior to an increase from the
manufacturer's commanded boost pressure that would cause an engine's
emissions to exceed the emissions thresholds for ``other monitors'' as
shown in Table 1 of this paragraph (g). For engines in which no failure
or deterioration of the boost pressure control system that causes an
increase in boost could result in an engine's emissions exceeding the
applicable emissions thresholds, the OBD system must detect a
malfunction when the system has reached its control limits such that it
cannot decrease boost to achieve the commanded boost pressure.
(C) VGT slow response. The OBD system must detect a malfunction
prior to any failure or deterioration in the capability of the VGT
system to achieve the commanded turbocharger geometry within a
manufacturer-specified time that would cause an engine's emissions to
exceed the emissions thresholds for ``other monitors'' as shown in
Table 1 of this paragraph (g). For engines in which no failure or
deterioration of the VGT system response could result in an engine's
emissions exceeding the applicable emissions thresholds, the OBD system
must detect a malfunction of the VGT system when proper functional
response of the system to computer commands does not occur.
(D) Turbo boost feedback control. See paragraph (i)(6) of this
section.
(E) Charge air undercooling. The OBD system must detect a
malfunction of the charge air cooling system prior to a decrease from
the manufacturer's specified cooling rate that would cause an engine's
emissions to exceed the emissions thresholds for ``other monitors'' as
shown in Table 1 of this paragraph (g). For engines in which no failure
or deterioration of the charge air cooling system that causes a
decrease in cooling performance could result in an engine's emissions
exceeding the applicable emissions thresholds, the OBD system must
detect a malfunction when the system has no detectable amount of charge
air cooling.
(iii) Turbo boost monitoring conditions.
(A) The OBD system must monitor continuously for malfunctions
identified in paragraphs (g)(4)(ii)(A), (g)(4)(ii)(B), and
(g)(4)(ii)(D) of this section.
(B) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraph (g)(4)(ii)(C) of this section in
accordance with paragraphs (c) and (d) of this section, with the
exception that monitoring must occur every time the monitoring
conditions are met during the drive cycle rather than once per drive
cycle as required in paragraph (c)(2) of this section. For purposes of
tracking and reporting as required in paragraph (d)(1) of this section,
all monitors used to detect malfunctions identified in paragraph
(g)(4)(ii)(C) of this section must be tracked separately but reported
as a single set of values as specified in paragraph (e)(1)(iii) of this
section.
(C) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraph (g)(4)(ii)(E) of this section in
accordance with paragraphs (c) and (d) of this section. For purposes of
tracking and reporting as required in paragraph (d)(1) of this section,
all monitors used to detect malfunctions identified in paragraph
(g)(4)(ii)(E) of this section must be tracked separately but reported
as a single set of values as specified in paragraph (e)(1)(iii) of this
section.
(iv) Turbo boost system MIL activation and DTC storage. The MIL
must activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(5) NMHC converting catalyst monitoring.
(i) General. The OBD system must monitor the NMHC converting
catalyst(s) for proper NMHC conversion capability. For engines equipped
with catalyzed diesel particulate filter(s) (DPF) that convert NMHC
emissions, the catalyst function of the DPF must be monitored in
accordance with the DPF requirements of paragraph (g)(8) of this
section. For purposes of this paragraph (g)(5), each catalyst that
converts NMHC must be monitored either individually or in combination
with others.
(ii) NMHC converting catalyst malfunction criteria.
(A) NMHC converting catalyst conversion efficiency. The OBD system
must detect a catalyst malfunction when the catalyst conversion
capability decreases to the point that NMHC emissions exceed the
emissions thresholds for the NMHC catalyst system as shown in Table 1
of this paragraph (g). If no failure or deterioration of the catalyst
NMHC conversion capability could result in an engine's NMHC emissions
exceeding the applicable emissions thresholds, the OBD system must
detect a malfunction when the catalyst has no detectable amount of NMHC
conversion capability.
(B) NMHC converting catalyst aftertreatment assistance functions.
For catalysts used to generate an exotherm to assist DPF regeneration,
the OBD system must detect a malfunction when the catalyst is unable to
generate a sufficient exotherm to achieve DPF regeneration. For
catalysts used to generate a feedgas constituency to assist selective
catalytic reduction (SCR) systems (e.g., to increase NO2
concentration upstream of an SCR system), the OBD system must detect a
malfunction when the catalyst is unable to generate the necessary
feedgas constituents for proper SCR system operation. For catalysts
located downstream of a DPF and used to convert NMHC emissions during
DPF regeneration, the OBD system must detect a malfunction when the
catalyst has no detectable amount of NMHC conversion capability.
[[Page 3298]]
(iii) NMHC converting catalyst monitoring conditions. The
manufacturer must define the monitoring conditions for malfunctions
identified in paragraphs (g)(5)(ii)(A) and (g)(5)(ii)(B) of this
section in accordance with paragraphs (c) and (d) of this section. For
purposes of tracking and reporting as required in paragraph (d)(1) of
this section, all monitors used to detect malfunctions identified in
paragraphs (g)(5)(ii)(A) and (g)(5)(ii)(B) of this section must be
tracked separately but reported as a single set of values as specified
in paragraph (e)(1)(iii) of this section.
(iv) NMHC converting catalyst MIL activation and DTC storage. The
MIL must activate and DTCs must be stored according to the provisions
of paragraph (b) of this section. The monitoring method for the NMHC
converting catalyst(s) must be capable of detecting all instances,
except diagnostic self-clearing, when a catalyst DTC has been erased
but the catalyst has not been replaced (e.g., catalyst over-temperature
histogram approaches are not acceptable).
(6) Selective catalytic reduction (SCR) and lean NOX catalyst
monitoring.
(i) General. The OBD system must monitor the SCR and/or the lean
NOX converting catalyst(s) for proper conversion capability.
For engines equipped with SCR systems or other catalyst systems that
use an active/intrusive reductant injection (e.g., active lean
NOX catalysts that use diesel fuel post-injection or in-
exhaust injection), the OBD system must monitor the active/intrusive
reductant injection system for proper performance. The individual
electronic components (e.g., actuators, valves, sensors, heaters,
pumps) in the active/intrusive reductant injection system must be
monitored in accordance with the comprehensive component requirements
in paragraph (i)(3) of this section. For purposes of this paragraph
(g)(6), each catalyst that converts NOX must be monitored
either individually or in combination with others.
(ii) SCR and lean NOX catalyst malfunction criteria.
(A) SCR and lean NOX catalyst conversion efficiency. The OBD system
must detect a catalyst malfunction when the catalyst conversion
capability decreases to the point that would cause an engine's
emissions to exceed the emissions thresholds for NOX
aftertreatment systems as shown in Table 1 of this paragraph (g). If no
failure or deterioration of the catalyst NOX conversion
capability could result in an engine's emissions exceeding any of the
applicable emissions thresholds, the OBD system must detect a
malfunction when the catalyst has no detectable amount of
NOX conversion capability.
(B) SCR and lean NOX catalyst active/intrusive reductant delivery
performance. The OBD system must detect a malfunction prior to any
failure or deterioration of the system to properly regulate reductant
delivery (e.g., urea injection, separate injector fuel injection, post
injection of fuel, air assisted injection/mixing) that would cause an
engine's emissions to exceed any of the applicable emissions thresholds
for NOX aftertreatment systems as shown in Table 1 of this
paragraph (g). If no failure or deterioration of the reductant delivery
system could result in an engine's emissions exceeding any of the
applicable thresholds, the OBD system must detect a malfunction when
the system has reached its control limits such that it is no longer
able to deliver the desired quantity of reductant.
(C) SCR and lean NOX catalyst active/intrusive reductant quantity.
If the SCR or lean NOX catalyst system uses a reductant
other than the fuel used for the engine, or uses a reservoir/tank for
the reductant that is separate from the fuel tank used for the engine,
the OBD system must detect a malfunction when there is no longer
sufficient reductant available (e.g., the reductant tank is empty).
(D) SCR and lean NOX catalyst active/intrusive reductant quality.
If the SCR or lean NOX catalyst system uses a reservoir/tank
for the reductant that is separate from the fuel tank used for the
engine, the OBD system must detect a malfunction when an improper
reductant is used in the reductant reservoir/tank (e.g., the reductant
tank is filled with something other than the reductant).
(E) SCR and lean NOX catalyst active/intrusive reductant feedback
control. See paragraph (i)(6) of this section.
(iii) SCR and lean NOX catalyst monitoring conditions.
(A) The manufacturers must define the monitoring conditions for
malfunctions identified in paragraphs (g)(6)(ii)(A) and (g)(6)(ii)(D)
of this section in accordance with paragraphs (c) and (d) of this
section. For purposes of tracking and reporting as required in
paragraph (d)(1) of this section, all monitors used to detect
malfunctions identified in paragraph (g)(6)(ii)(A) of this section must
be tracked separately but reported as a single set of values as
specified in paragraph (e)(1)(iii) of this section.
(B) The OBD system must monitor continuously for malfunctions
identified in paragraphs (g)(6)(ii)(B), (g)(6)(ii)(C), and
(g)(6)(ii)(E) of this section.
(iv) SCR and lean NOX catalyst MIL activation and DTC
storage.
(A) For malfunctions identified in paragraph (g)(6)(ii)(A) of this
section, the MIL must activate and DTCs must be stored according to the
provisions of paragraph (b) of this section.
(B) For malfunctions identified in paragraphs (g)(6)(ii)(B),
(g)(6)(ii)(C), and (g)(6)(ii)(D) of this section, the manufacturer may
delay activating the MIL if the vehicle is equipped with an alternative
indicator for notifying the vehicle operator of the malfunction. The
alternative indicator must be of sufficient illumination and be located
such that it is readily visible to the vehicle operator under all
lighting conditions. If the vehicle is not equipped with such an
alternative indicator and the OBD MIL activates, the MIL may be
immediately deactivated and the corresponding DTC(s) erased once the
OBD system has verified that the reductant tank has been refilled
properly and the MIL has not been activated for any other malfunction.
The Administrator may approve other strategies that provide equivalent
assurance that a vehicle operator would be promptly notified and that
corrective action would be taken.
(C) The monitoring method for the SCR and lean NOX
catalyst(s) must be capable of detecting all instances, except
diagnostic self-clearing, when a catalyst DTC(s) has been erased but
the catalyst has not been replaced (e.g., catalyst over-temperature
histogram approaches are not acceptable).
(7) NOX adsorber system monitoring.
(i) General. The OBD system must monitor the NOX
adsorber on engines so-equipped for proper performance. For engines
equipped with active/intrusive injection (e.g., in-exhaust fuel and/or
air injection) to achieve desorption of the NOX adsorber,
the OBD system must monitor the active/intrusive injection system for
proper performance. The individual electronic components (e.g.,
injectors, valves, sensors) that are used in the active/intrusive
injection system must be monitored in accordance with the comprehensive
component requirements in paragraph (i)(3) of this section.
(ii) NOX adsorber system malfunction criteria.
(A) NOX adsorber system capability. The OBD system must
detect a NOX adsorber malfunction when its capability (i.e.,
its combined adsorption and conversion capability) decreases to
[[Page 3299]]
the point that would cause an engine's NOX emissions to
exceed the emissions thresholds for NOX aftertreatment
systems as shown in Table 1 of this paragraph (g). If no failure or
deterioration of the NOX adsorber capability could result in
an engine's NOX emissions exceeding the applicable emissions
thresholds, the OBD system must detect a malfunction when the system
has no detectable amount of NOX adsorber capability.
(B) NOX adsorber system active/intrusive reductant
delivery performance. For NOX adsorber systems that use
active/intrusive injection (e.g., in-cylinder post fuel injection, in-
exhaust air-assisted fuel injection) to achieve desorption of the
NOX adsorber, the OBD system must detect a malfunction if
any failure or deterioration of the injection system's ability to
properly regulate injection causes the system to be unable to achieve
desorption of the NOX adsorber.
(C) NOX adsorber system feedback control. Malfunction
criteria for the NOX adsorber and the NOX
adsorber active/instrusive reductant delivery system are contained in
paragraph (i)(6)of this section.
(iii) NOX adsorber system monitoring conditions.
(A) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraph (g)(7)(ii)(A) of this section in
accordance with paragraphs (c) and (d) of this section. For purposes of
tracking and reporting as required in paragraph (d)(1) of this section,
all monitors used to detect malfunctions identified in paragraph
(g)(7)(ii)(A) of this section must be tracked separately but reported
as a single set of values as specified in paragraph (e)(1)(iii) of this
section.
(B) The OBD system must monitor continuously for malfunctions
identified in paragraphs (g)(7)(ii)(B) and (g)(7)(ii)(C) of this
section.
(iv) NOX adsorber system MIL activation and DTC storage.
The MIL must activate and DTCs must be stored according to the
provisions of paragraph (b) of this section.
(8) Diesel particulate filter (DPF) system monitoring.
(i) General. The OBD system must monitor the DPF on engines so-
equipped for proper performance. For engines equipped with active
regeneration systems that use an active/intrusive injection (e.g., in-
exhaust fuel injection, in-exhaust fuel/air burner), the OBD system
must monitor the active/intrusive injection system for proper
performance. The individual electronic components (e.g., injectors,
valves, sensors) that are used in the active/intrusive injection system
must be monitored in accordance with the comprehensive component
requirements in paragraph (i)(3) of this section.
(ii) DPF system malfunction criteria.
(A) DPF filtering performance. The OBD system must detect a
malfunction prior to a decrease in the PM filtering capability of the
DPF (e.g., cracking, melting, etc.) that would cause an engine's PM
emissions to exceed the emissions thresholds for DPF systems as shown
in Table 1 of this paragraph (g). If no failure or deterioration of the
PM filtering performance could result in an engine's PM emissions
exceeding the applicable emissions thresholds, the OBD system must
detect a malfunction when no detectable amount of PM filtering occurs.
(B) DPF regeneration frequency. The OBD system must detect a
malfunction when the DPF regeneration frequency increases from (i.e.,
occurs more often than) the manufacturer's specified regeneration
frequency to a level such that it would cause an engine's NMHC
emissions to exceed the emissions threshold for DPF systems as shown in
Table 1 of this paragraph (g). If no such regeneration frequency exists
that could cause NMHC emissions to exceed the applicable emission
threshold, the OBD system must detect a malfunction when the DPF
regeneration frequency exceeds the manufacturer's specified design
limits for allowable regeneration frequency.
(C) DPF incomplete regeneration. The OBD system must detect a
regeneration malfunction when the DPF does not properly regenerate
under manufacturer-defined conditions where regeneration is designed to
occur.
(D) DPF NMHC conversion. For any DPF that serves to convert NMHC
emissions, the OBD system must detect a malfunction when the NMHC
conversion capability decreases to the point that NMHC emissions exceed
the emissions threshold for DPF systems as shown in Table 1 of this
paragraph (g). If no failure or deterioration of the NMHC conversion
capability could result in NMHC emissions exceeding the applicable
threshold, the OBD system must detect a malfunction when the system has
no detectable amount of NMHC conversion capability.
(E) DPF missing substrate. The OBD system must detect a malfunction
if either the DPF substrate is completely destroyed, removed, or
missing, or if the DPF assembly has been replaced with a muffler or
straight pipe.
(F) DPF system active/intrusive injection. For DPF systems that use
active/intrusive injection (e.g., in-cylinder post fuel injection, in-
exhaust air-assisted fuel injection) to achieve regeneration of the
DPF, the OBD system must detect a malfunction if any failure or
deterioration of the injection system's ability to properly regulate
injection causes the system to be unable to achieve regeneration of the
DPF.
(G) DPF regeneration feedback control. See paragraph (i)(6) of this
section.
(iii) DPF monitoring conditions. The manufacturer must define the
monitoring conditions for malfunctions identified in paragraph
(g)(8)(ii) of this section in accordance with paragraphs (c) and (d) of
this section, with the exception that monitoring must occur every time
the monitoring conditions are met during the drive cycle rather than
once per drive cycle as required in paragraph (c)(2) of this section.
For purposes of tracking and reporting as required in paragraph (d)(1)
of this section, all monitors used to detect malfunctions identified in
paragraph (g)(8)(ii) of this section must be tracked separately but
reported as a single set of values as specified in paragraph
(e)(1)(iii) of this section.
(iv) DPF system MIL activation and DTC storage. The MIL must
activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(9) Exhaust gas sensor and sensor heater monitoring.
(i) General. The OBD system must monitor for proper output signal,
activity, response rate, and any other parameter that can affect
emissions, all exhaust gas sensors (e.g., oxygen, air-fuel ratio,
NOX) used for emission control system feedback (e.g., EGR
control/feedback, SCR control/feedback, NOX adsorber
control/feedback) and/or as a monitoring device. For engines equipped
with heated exhaust gas sensors, the OBD system must monitor the heater
for proper performance.
(ii) Malfunction criteria for air-fuel ratio sensors located
upstream of aftertreatment devices.
(A) Sensor performance. The OBD system must detect a malfunction
prior to any failure or deterioration of the sensor voltage,
resistance, impedance, current, response rate, amplitude, offset, or
other characteristic(s) that would cause an engine's emissions to
exceed the emissions thresholds for ``other monitors'' as shown in
Table 1 of this paragraph (g).
(B) Circuit integrity. The OBD system must detect malfunctions of
the sensor related to a lack of circuit continuity or signal out-of-
range values.
(C) Feedback function. The OBD system must detect a malfunction of
the
[[Page 3300]]
sensor if the emission control system (e.g., EGR, SCR, or
NOX adsorber) is unable to use that sensor as a feedback
input (e.g., causes limp-home or open-loop operation).
(D) Monitoring function. To the extent feasible, the OBD system
must detect a malfunction of the sensor when the sensor output voltage,
resistance, impedance, current, amplitude, activity, offset, or other
characteristics are no longer sufficient for use as an OBD system
monitoring device (e.g., for catalyst, EGR, SCR, or NOX
adsorber monitoring).
(iii) Malfunction criteria for air-fuel ratio sensors located
downstream of aftertreatment devices.
(A) Sensor performance. The OBD system must detect a malfunction
prior to any failure or deterioration of the sensor voltage,
resistance, impedance, current, response rate, amplitude, offset, or
other characteristic(s) that would cause an engine's emissions to
exceed the emissions thresholds for air-fuel ratio sensors downstream
of aftertreatment devices as shown in Table 1 of this paragraph (g).
(B) Circuit integrity. The OBD system must detect malfunctions of
the sensor related to a lack of circuit continuity or signal out-of-
range values.
(C) Feedback function. The OBD system must detect a malfunction of
the sensor if the emission control system (e.g., EGR, SCR, or
NOX adsorber) is unable to use that sensor as a feedback
input (e.g., causes limp-home or open-loop operation).
(D) Monitoring function. To the extent feasible, the OBD system
must detect a malfunction of the sensor when the sensor output voltage,
resistance, impedance, current, amplitude, activity, offset, or other
characteristics are no longer sufficient for use as an OBD system
monitoring device (e.g., for catalyst, EGR, SCR, or NOX
adsorber monitoring).
(iv) Malfunction criteria for NOX sensors.
(A) Sensor performance. The OBD system must detect a malfunction
prior to any failure or deterioration of the sensor voltage,
resistance, impedance, current, response rate, amplitude, offset, or
other characteristic(s) that would cause an engine's emissions to
exceed the emissions thresholds for NOX sensors as shown in
Table 1 of this paragraph (g).
(B) Circuit integrity. The OBD system must detect malfunctions of
the sensor related to a lack of circuit continuity or signal out-of-
range values.
(C) Feedback function.The OBD system must detect a malfunction of
the sensor if the emission control system (e.g., EGR, SCR, or
NOX adsorber) is unable to use that sensor as a feedback
input (e.g., causes limp-home or open-loop operation).
(D) Monitoring function. To the extent feasible, the OBD system
must detect a malfunction of the sensor when the sensor output voltage,
resistance, impedance, current, amplitude, activity, offset, or other
characteristics are no longer sufficient for use as an OBD system
monitoring device (e.g., for catalyst, EGR, SCR, or NOX
adsorber monitoring).
(v) Malfunction criteria for other exhaust gas sensors. For other
exhaust gas sensors, the manufacturer must submit a monitoring plan to
the Administrator for approval. The plan must include data and/or
engineering evaluations that demonstrate that the monitoring plan is as
reliable and effective as the monitoring required in paragraphs
(g)(9)(ii) through (g)(9)(iv) of this section.
(vi) Malfunction criteria for exhaust gas sensor heaters.
(A) The OBD system must detect a malfunction of the heater
performance when the current or voltage drop in the heater circuit is
no longer within the manufacturer's specified limits for normal
operation (i.e., within the criteria required to be met by the
component vendor for heater circuit performance at high mileage). The
manufacturer may use other malfunction criteria for heater performance
malfunctions. To do so, the manufacturer must be able to demonstrate
via data and/or an engineering evaluation that the monitor is reliable
and robust.
(B) The OBD system must detect malfunctions of the heater circuit
including open or short circuits that conflict with the commanded state
of the heater (e.g., shorted to 12 Volts when commanded to 0 Volts
(ground)).
(vii) Monitoring conditions for exhaust gas sensors.
(A) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraphs (g)(9)(ii)(A), (g)(9)(iii)(A),
and (g)(9)(iv)(A) of this section (i.e., sensor performance) in
accordance with paragraphs (c) and (d) of this section. For purposes of
tracking and reporting as required in paragraph (d)(1) of this section,
all monitors used to detect malfunctions identified in paragraphs
(g)(9)(ii)(A), (g)(9)(iii)(A), and (g)(9)(iv)(A) of this section must
be tracked separately but reported as a single set of values as
specified in paragraph (e)(1)(iii) of this section.
(B) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraphs (g)(9)(ii)(D), (g)(9)(iii)(D),
and (g)(9)(iv)(D) of this section (i.e., monitoring function) in
accordance with paragraphs (c) and (d) of this section with the
exception that monitoring must occur every time the monitoring
conditions are met during the drive cycle rather than once per drive
cycle as required in paragraph (c)(2) of this section.
(C) Except as provided for in paragraph (g)(9)(vii)(D) of this
paragraph (g)(9), the OBD system must monitor continuously for
malfunctions identified in paragraphs (g)(9)(ii)(B), (g)(9)(ii)(C),
(g)(9)(iii)(B), (g)(9)(iii)(C), (g)(9)(iv)(B), and (g)(9)(iv)(C) (i.e.,
circuit integrity and feedback function).
(D) A manufacturer may request approval to disable continuous
exhaust gas sensor monitoring when an exhaust gas sensor malfunction
cannot be distinguished from other effects (e.g., disable monitoring
for out-of-range on the low side during fuel cut conditions). To do so,
the manufacturer must demonstrate via data and/or engineering analyses
that a properly functioning sensor cannot be distinguished from a
malfunctioning sensor and that the disablement interval is limited only
to that necessary for avoiding false malfunction detection.
(viii) Monitoring conditions for exhaust gas sensor heaters.
(A) The manufacturer must define monitoring conditions for
malfunctions identified in paragraph (g)(9)(vi)(A) of this section
(i.e., sensor heater performance) in accordance with paragraphs (c) and
(d) of this section.
(B) The OBD system must monitor continuously for malfunctions
identified in paragraph (g)(9)(vi)(B) of this section (i.e., circuit
malfunctions).
(ix) Exhaust gas sensor and sensor heater MIL activation and DTC
storage. The MIL must activate and DTCs must be stored according to the
provisions of paragraph (b) of this section.
(10) Variable Valve Timing (VVT) system monitoring.
(i) General. The OBD system must monitor the VVT system on engines
so equipped for target error and slow response malfunctions. The
individual electronic components (e.g., actuators, valves, sensors)
that are used in the VVT system must be monitored in accordance with
the comprehensive components requirements in paragraph (i)(3) of this
section.
(ii) VVT system malfunction criteria.
(A) VVT system target error. The OBD system must detect a
malfunction prior to any failure or deterioration in the capability of
the VVT system to achieve the commanded valve timing and/or control
within a crank angle and/or lift tolerance that would cause an engine's
[[Page 3301]]
emissions to exceed the emission thresholds for ``other monitors'' as
shown in Table 1 of this paragraph (g).
(B) VVT slow response. The OBD system must detect a malfunction
prior to any failure or deterioration in the capability of the VVT
system to achieve the commanded valve timing and/or control within a
manufacturer-specified time that would cause an engine's emissions to
exceed the emission thresholds for ``other monitors'' as shown in Table
1 of this paragraph (g).
(C) For engines in which no failure or deterioration of the VVT
system could result in an engine's emissions exceeding the applicable
emissions thresholds of paragraphs (g)(10)(ii)(A) and (g)(10)(ii)(B) of
this section, the OBD system must detect a malfunction of the VVT
system when proper functional response of the system to computer
commands does not occur.
(iii) VVT system monitoring conditions. Manufacturers must define
the monitoring conditions for VVT system malfunctions identified in
paragraph (g)(10)(ii) of this section in accordance with paragraphs (c)
and (d) of this section, with the exception that monitoring must occur
every time the monitoring conditions are met during the drive cycle
rather than once per drive cycle as required in paragraph (c)(2) of
this section. For purposes of tracking and reporting as required in
paragraph (d)(1) of this section, all monitors used to detect
malfunctions identified in paragraph (g)(10)(ii) of this section must
be tracked separately but reported as a single set of values as
specified in paragraph (e)(1)(iii) of this section.
(iv) VVT MIL activation and DTC storage. The MIL must activate and
DTCs must be stored according to the provisions of paragraph (b) of
this section.
(h) OBD monitoring requirements for gasoline-fueled/spark-ignition
engines. The following table shows the thresholds at which point
certain components or systems, as specified in this paragraph (h), are
considered malfunctioning.
Table 2.--OBD Emissions Thresholds for Gasoline-Fueled/Spark-Ignition Engines Meant for Placement in
Applications Greater Than 14,000 Pounds GVWR (g/bhp-hr)
----------------------------------------------------------------------------------------------------------------
Sec. 86.010-18
Component NOX NMHC CO reference
----------------------------------------------------------------------------------------------------------------
Catalyst system................. 1.75x std........ 1.75x std.......... ................. (h)(6).
Evaporative emissions control ................. 0.150 inch leak.... ................. (h)(7).
system.
``Other monitors'' with 1.5x std......... 1.5x std........... 1.5x std......... (h)(1), (h)(2),
emissions thresholds. (h)(3), (h)(4),
(h)(5), (h)(8),
(h)(9).
----------------------------------------------------------------------------------------------------------------
Notes: 1.75x std means a multiple of 1.75 times the applicable emissions standard; these emissions thresholds
apply to the monitoring requirements of paragraph (h) of this section 86.010-18; The evaporative emissions
control system threshold is not, technically, an emissions threshold but rather a leak size that must be
detected; nonetheless, for ease we refer to this as the threshold.
(1) Fuel system monitoring.
(i) General. The OBD system must monitor the fuel delivery system
to determine its ability to provide compliance with emission standards.
(ii) Fuel system malfunction criteria.
(A) The OBD system must detect a malfunction of the fuel delivery
system (including feedback control based on a secondary oxygen sensor)
when the fuel delivery system is unable to maintain an engine's
emissions at or below the emissions thresholds for ``other monitors''
as shown in Table 2 of this paragraph (h).
(B) Except as provided for in paragraph (h)(1)(ii)(C) of this
section, if the engine is equipped with adaptive feedback control, the
OBD system must detect a malfunction when the adaptive feedback control
has used up all of the adjustment allowed by the manufacturer.
(C) If the engine is equipped with feedback control that is based
on a secondary oxygen (or equivalent) sensor, the OBD system is not
required to detect a malfunction of the fuel system solely when the
feedback control based on a secondary oxygen sensor has used up all of
the adjustment allowed by the manufacturer. However, if a failure or
deterioration results in engine emissions that exceed the emissions
thresholds for ``other monitors'' as shown in Table 2 of this paragraph
(h), the OBD system is required to detect a malfunction.
(D) The OBD system must detect a malfunction whenever the fuel
control system fails to enter closed loop operation following engine
start within a manufacturer specified time interval. The specified time
interval must be supported by data and/or engineering analyses
submitted by the manufacturer.
(E) The manufacturer may adjust the malfunction criteria and/or
monitoring conditions to compensate for changes in altitude, for
temporary introduction of large amounts of purge vapor, or for other
similar identifiable operating conditions when such conditions occur.
(iii) Fuel system monitoring conditions. The fuel system must be
monitored continuously for the presence of a malfunction.
(iv) Fuel system MIL activation and DTC storage.
(A) A pending DTC must be stored immediately upon the fuel system
exceeding the malfunction criteria established in paragraph (h)(1)(ii)
of this section.
(B) Except as provided for in paragraph (h)(1)(iv)(C) of this
section, if a pending DTC is stored, the OBD system must activate the
MIL immediately and store a MIL-on DTC if a malfunction is again
detected during either the drive cycle immediately following storage of
the pending DTC regardless of the conditions encountered during that
drive cycle, or on the next drive cycle in which similar conditions are
encountered to those that occurred when the pending DTC was stored.
Similar conditions means engine conditions having an engine speed
within 375 rpm, load conditions within 20 percent, and the same warm up
status (i.e., cold or hot) as the engine conditions stored pursuant to
paragraph (h)(1)(iv)(E) of this section. Other definitions of similar
conditions may be used but must result in comparable timeliness and
reliability in detecting similar engine operation.
(C) The pending DTC may be erased at the end of the next drive
cycle in which similar conditions have been encountered without having
again exceeded the specified fuel system malfunction criteria. The
pending DTC may also be erased if similar conditions are not
encountered during the 80 drive cycles immediately following detection
of the potential malfunction for which the pending DTC was stored.
(D) Storage of freeze frame conditions. The OBD system must store
and erase freeze frame conditions either in conjunction with storing
and erasing a pending DTC or in conjunction with storing and erasing a
MIL-on DTC. Freeze frame information associated with a fuel system
malfunction shall be
[[Page 3302]]
stored in preference to freeze frame information required elsewhere in
paragraphs (h) or (i) of this section.
(E) Storage of fuel system conditions for determining similar
conditions of operation. The OBD must store the engine speed, load, and
warm-up status present at the time it first detects a potential
malfunction meeting the criteria of paragraph (h)(1)(ii) of this
section and stores a pending DTC.
(F) Deactivating the MIL. The MIL may be extinguished after three
sequential driving cycles in which similar conditions have been
encountered without detecting a malfunction of the fuel system.
(2) Engine misfire monitoring.
(i) General.
(A) The OBD system must monitor the engine for misfire causing
catalyst damage and misfire causing excess emissions.
(B) The OBD system must identify the specific cylinder that is
misfiring. The manufacturer may store a general misfire DTC instead of
a cylinder specific DTC under certain operating conditions. To do so,
the manufacturer must submit data and/or engineering analyses that
demonstrate that the misfiring cylinder cannot be identified reliably
when the conditions occur.
(C) If more than one cylinder is misfiring, a separate DTC must be
stored to indicate that multiple cylinders are misfiring unless
otherwise allowed by this paragraph (h)(2). When identifying multiple
cylinder misfire, the OBD system is not required to also identify using
separate DTCs each of the misfiring cylinders individually. If more
than 90 percent of the detected misfires occur in a single cylinder, an
appropriate DTC may be stored that indicates the specific misfiring
cylinder rather than storing the multiple cylinder misfire DTC. If two
or more cylinders individually have more than 10 percent of the total
number of detected misfires, a multiple cylinder DTC must be stored.
(ii) Engine misfire malfunction criteria.
(A) Misfire causing catalyst damage. The manufacturer must
determine the percentage of misfire evaluated in 200 revolution
increments for each engine speed and load condition that would result
in a temperature that causes catalyst damage. If this percentage of
misfire is exceeded, it shall be considered a malfunction that must be
detected. For every engine speed and load condition for which this
percentage of misfire is determined to be lower than five percent, the
manufacturer may set the malfunction criteria at five percent. The
manufacturer may use a longer interval than 200 revolutions but only
for determining, on a given drive cycle, the first misfire exceedance
as provided in paragraph (h)(2)(iv)(A) of this section. To do so, the
manufacturer must demonstrate that the interval is not so long that
catalyst damage would occur prior to the interval being elapsed.
(B) Misfire causing emissions to exceed the applicable thresholds.
The manufacturer must determine the percentage of misfire evaluated in
1000 revolution increments that would cause emissions from an emissions
durability demonstration engine to exceed the emissions thresholds for
``other monitors'' as shown in Table 2 of this paragraph (h) if that
percentage of misfire were present from the beginning of the test. If
this percentage of misfire is exceeded, regardless of the pattern of
misfire events (e.g., random, equally spaced, continuous), it shall be
considered a malfunction that must be detected. To establish this
percentage of misfire, the manufacturer must use misfire events
occurring at equally spaced, complete engine cycle intervals, across
randomly selected cylinders throughout each 1000-revolution increment.
If this percentage of misfire is determined to be lower than one
percent, the manufacturer may set the malfunction criteria at one
percent. The manufacturer may use a longer interval than 1000
revolutions. To do so, the manufacturer must demonstrate that the
strategy would be equally effective and timely at detecting misfire.
(iii) Engine misfire monitoring conditions.
(A) The OBD system must monitor continuously for misfire under the
following conditions: from no later than the end of the second
crankshaft revolution after engine start; during the rise time and
settling time for engine speed to reach the desired idle engine speed
at engine start-up (i.e., ``flare-up'' and ``flare-down''); and, under
all positive torque engine speeds and load conditions except within the
engine operating region bound by the positive torque line (i.e., engine
load with the transmission in neutral), and the points represented by
an engine speed of 3000 rpm with the engine load at the positive torque
line and the redline engine speed with the engine's manifold vacuum at
four inches of mercury lower than that at the positive torque line. For
this purpose, redline engine speed is defined as either the recommended
maximum engine speed as displayed on the instrument panel tachometer,
or the engine speed at which fuel shutoff occurs.
(B) If an OBD monitor cannot detect all misfire patterns under all
required engine speed and load conditions as required by paragraph
(h)(2)(iii)(A) of this section, the OBD system may still be acceptable.
The Administrator will evaluate the following factors in making a
determination: the magnitude of the region(s) in which misfire
detection is limited; the degree to which misfire detection is limited
in the region(s) (i.e., the probability of detection of misfire
events); the frequency with which said region(s) are expected to be
encountered in-use; the type of misfire patterns for which misfire
detection is troublesome; and demonstration that the monitoring
technology employed is not inherently incapable of detecting misfire
under the required conditions (i.e., compliance can be achieved on
other engines). The evaluation will be based on the following misfire
patterns: equally spaced misfire occurring on randomly selected
cylinders; single cylinder continuous misfire; and paired cylinder
(cylinders firing at the same crank angle) continuous misfire.
(C) The manufacturer may use monitoring system that has reduced
misfire detection capability during the portion of the first 1000
revolutions after engine start that a cold start emission reduction
strategy is active that reduces engine torque (e.g., spark retard
strategies). To do so, the manufacturer must demonstrate that the
probability of detection is greater than or equal to 75 percent during
the worst case condition (i.e., lowest generated torque) for a vehicle
operated continuously at idle (park/neutral idle) on a cold start
between 50 and 86 degrees Fahrenheit and that the technology cannot
reliably detect a higher percentage of the misfire events during the
conditions.
(D) The manufacturer may disable misfire monitoring or use an
alternative malfunction criterion when misfire cannot be distinguished
from other effects. To do so, the manufacturer must demonstrate that
the disablement interval or the period of use of an alternative
malfunction criterion is limited only to that necessary for avoiding
false detection and for one or more of the following operating
conditions: rough road; fuel cut; gear changes for manual transmission
vehicles; traction control or other vehicle stability control
activation such as anti-lock braking or other engine torque
modifications to enhance vehicle stability; off-board control or
intrusive activation of vehicle components or monitors during service
or assembly plant testing; portions of intrusive evaporative system or
EGR monitors that can significantly affect engine stability (i.e.,
while the purge valve is open during the vacuum pull-down of a
[[Page 3303]]
evaporative system leak check but not while the purge valve is closed
and the evaporative system is sealed or while an EGR monitor causes the
EGR valve to be cycled intrusively on and off during positive torque
conditions); or, engine speed, load, or torque transients due to
throttle movements more rapid than those that occur over the FTP cycle
for the worst case engine within each engine family. In general, the
Administrator will not approve disablement for conditions involving
normal air conditioning compressor cycling from on-to-off or off-to-on,
automatic transmission gear shifts (except for shifts occurring during
wide open throttle operation), transitions from idle to off-idle,
normal engine speed or load changes that occur during the engine speed
rise time and settling time (i.e., ``flare-up'' and ``flare-down'')
immediately after engine starting without any vehicle operator-induced
actions (e.g., throttle stabs), or excess acceleration (except for
acceleration rates that exceed the maximum acceleration rate obtainable
at wide open throttle while the vehicle is in gear due to abnormal
conditions such as slipping of a clutch).
(iv) MIL activation and DTC storage for engine misfire causing
catalyst damage.
(A) Pending DTCs. A pending DTC must be stored immediately if,
during a single drive cycle, the specified misfire percentage described
in paragraph (h)(2)(ii)(A) of this section is exceeded three times when
operating in the positive torque region encountered during a FTP cycle
or is exceeded on a single occasion when operating at any other engine
speed and load condition in the positive torque region defined in
paragraph (h)(2)(iii)(A) of this section. Immediately after a pending
DTC is stored pursuant to this paragraph, the MIL must blink once per
second at all times during the drive cycle that engine misfire is
occurring. The MIL may be deactivated during those times that misfire
is not occurring. If, at the time that a catalyst damaging misfire
malfunction occurs, the MIL is already activated for a malfunction
other than misfire, the MIL must still blink once per second at all
times during the drive cycle that engine misfire is occurring. If
misfire ceases, the MIL must stop blinking but remain activated as
appropriate in accordance with the other malfunction.
(B) MIL-on DTCs. If a pending DTC is stored in accordance with
paragraph (h)(2)(iv)(A) of this section, the OBD system must
immediately store a MIL-on DTC if the percentage of misfire described
in paragraph (h)(2)(ii)(A) of this section is again exceeded one or
more times during either the drive cycle immediately following storage
of the pending DTC, regardless of the conditions encountered during
that drive cycle, or on the next drive cycle in which similar
conditions are encountered to those that occurred when the pending DTC
was stored. If, during a previous drive cycle, a pending DTC is stored
in accordance with paragraph (h)(2)(iv)(A) of this section, a MIL-on
DTC must be stored immediately upon exceeding the percentage misfire
described in paragraph (h)(2)(ii)(A) of this section regardless of the
conditions encountered. Upon storage of a MIL-on DTC, the MIL must
blink once per second at all times during the drive cycle that engine
misfire is occurring. If misfire ceases, the MIL must stop blinking but
remain activated until the conditions are met for extinguishing the
MIL.
(C) Erasure of pending DTCs. Pending DTCs stored in accordance with
paragraph (h)(2)(iv)(A) of this section must be erased at the end of
the next drive cycle in which similar conditions are encountered to
those that occurred when the pending DTC was stored provided no
exceedances have been detected of the misfire percentage described in
paragraph (h)(2)(ii)(A) of this section. The pending DTC may also be
erased if similar conditions are not encountered during the next 80
drive cycles immediately following storage of the pending DTC.
(D) Exemptions for engines with fuel shutoff and default fuel
control. In engines that provide for fuel shutoff and default fuel
control to prevent over fueling during catalyst damaging misfire
conditions, the MIL need not blink as required by paragraphs
(h)(2)(iv)(A) and (h)(2)(iv)(B) of this section. Instead, the MIL may
be activated continuously upon misfire detection provided that the fuel
shutoff and default fuel control are activated immediately upon misfire
detection. Fuel shutoff and default fuel control may be deactivated
only when the engine is outside of the misfire range except that the
manufacturer may periodically, but not more than once every 30 seconds,
deactivate fuel shutoff and default fuel control to determine if the
catalyst damaging misfire is still occurring. Normal fueling and fuel
control may be resumed if the catalyst damaging misfire is no longer
occurring.
(E) The manufacturer may use a strategy that activates the MIL
continuously rather than blinking the MIL during extreme catalyst
damage misfire conditions (i.e., catalyst damage misfire occurring at
all engine speeds and loads). Use of such a strategy must be limited to
catalyst damage misfire levels that cannot be avoided during reasonable
driving conditions. To use such a strategy, the manufacturer must be
able to demonstrate that the strategy will encourage operation of the
vehicle in conditions that will minimize catalyst damage (e.g., at low
engine speeds and loads).
(v) MIL activation and DTC storage for engine misfire causing
emissions to exceed applicable emissions thresholds.
(A) Immediately upon detection, during the first 1000 revolutions
after engine start of the misfire percentage described in paragraph
(h)(2)(ii)(B) of this section, a pending DTC must be stored. If such a
pending DTC is stored already and another such exceedance of the
misfire percentage is detected within the first 1000 revolutions after
engine start on any subsequent drive cycle, the MIL must activate and a
MIL-on DTC must be stored. The pending DTC may be erased if, at the end
of the next drive cycle in which similar conditions are encountered to
those that occurred when the pending DTC was stored, there has been no
exceedance of the misfire percentage described in paragraph
(h)(2)(ii)(B) of this section. The pending DTC may also be erased if
similar conditions are not encountered during the next 80 drive cycles
immediately following storage of the pending DTC.
(B) No later than the fourth detection during a single drive cycle,
following the first 1000 revolutions after engine start of the misfire
percentage described in paragraph (h)(2)(ii)(B) of this section, a
pending DTC must be stored. If such a pending DTC is stored already,
then the MIL must activate and a MIL-on DTC must be stored within 10
seconds of the fourth detection of the misfire percentage described in
paragraph (h)(2)(ii)(B) of this section during either the drive cycle
immediately following storage of the pending DTC, regardless of the
conditions encountered during that drive cycle excepting those
conditions within the first 1000 revolutions after engine start, or on
the next drive cycle in which similar conditions are encountered to
those that occurred when the pending DTC was stored excepting those
conditions within the first 1000 revolutions after engine start. The
pending DTC may be erased if, at the end of the next drive cycle in
which similar conditions are encountered to those that occurred when
the pending DTC was stored, there has been no exceedance of the misfire
percentage described in paragraph (h)(2)(ii)(B) of this section. The
pending DTC may also be erased if
[[Page 3304]]
similar conditions are not encountered during the next 80 drive cycles
immediately following storage of the pending DTC.
(vi) Storage of freeze frame conditions for engine misfire.
(A) The OBD system must store and erase freeze frame conditions (as
defined in paragraph (k)(4)(iii) of this section) either in conjunction
with storing and erasing a pending DTC or in conjunction with storing
and erasing a MIL-on DTC.
(B) If, upon storage of a DTC as required by paragraphs (h)(2)(iv)
and (h)(2)(v) of this section, there already exist stored freeze frame
conditions for a malfunction other than a misfire or fuel system
malfunction (see paragraph (h)(1) of this section) then the stored
freeze frame information shall be replaced with freeze frame
information associated with the misfire malfunction.
(vii) Storage of engine conditions in association with engine
misfire. Upon detection of the misfire percentages described in
paragraphs (h)(2)(ii)(A) and (h)(2)(ii)(B) of this section, the
following engine conditions must be stored for use in determining
similar conditions: engine speed, load, and warm up status of the first
misfire event that resulted in pending DTC storage.
(viii) MIL deactivation in association with engine misfire. The MIL
may be deactivated after three sequential drive cycles in which similar
conditions have been encountered without an exceedance of the misfire
percentages described in paragraphs (h)(2)(ii)(A) and (h)(2)(ii)(B) of
this section.
(3) Exhaust gas recirculation system monitoring.
(i) General. The OBD system must monitor the EGR system on engines
so equipped for low and high flow rate malfunctions. The individual
electronic components (e.g., actuators, valves, sensors) that are used
in the EGR system must be monitored in accordance with the
comprehensive component requirements in paragraph (i)(3) of this
section.
(ii) EGR system malfunction criteria.
(A) The OBD system must detect a malfunction of the EGR system
prior to a decrease from the manufacturer's specified EGR flow rate
that would cause an engine's emissions to exceed the emissions
thresholds for ``other monitors'' as shown in Table 2 of this paragraph
(h). For engines in which no failure or deterioration of the EGR system
that causes a decrease in flow could result in an engine's emissions
exceeding the applicable emissions thresholds, the OBD system must
detect a malfunction when the system has no detectable amount of EGR
flow.
(B) The OBD system must detect a malfunction of the EGR system
prior to an increase from the manufacturer's specified EGR flow rate
that would cause an engine's emissions to exceed the emissions
thresholds for ``other monitors'' as shown in Table 2 of this paragraph
(h). For engines in which no failure or deterioration of the EGR system
that causes an increase in flow could result in an engine's emissions
exceeding the applicable emissions thresholds, the OBD system must
detect a malfunction when the system has reached its control limits
such that it cannot reduce EGR flow.
(iii) EGR system monitoring conditions.
(A) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraph (h)(3)(ii) of this section in
accordance with paragraphs (c) and (d) of this section. For purposes of
tracking and reporting as required by paragraph (d)(1) of this section,
all monitors used to detect malfunctions identified in paragraph
(h)(3)(ii) of this section must be tracked separately but reported as a
single set of values as specified in paragraph (e)(1)(iii) of this
section.
(B) The manufacturer may disable temporarily the EGR monitor under
conditions when monitoring may not be reliable (e.g., when freezing may
affect performance of the system). To do so, the manufacturer must be
able to demonstrate that the monitor is unreliable when such conditions
exist.
(iv) EGR system MIL activation and DTC storage. The MIL must
activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(4) Cold start emission reduction strategy monitoring.
(i) General. If an engine incorporates a specific engine control
strategy to reduce cold start emissions, the OBD system must monitor
the key components (e.g., idle air control valve), other than secondary
air, while the control strategy is active to ensure proper operation of
the control strategy.
(ii) Cold start strategy malfunction criteria.
(A) The OBD system must detect a malfunction prior to any failure
or deterioration of the individual components associated with the cold
start emission reduction control strategy that would cause an engine's
emissions to exceed the emissions thresholds for ``other monitors'' as
shown in Table 2 of this paragraph (h). The manufacturer must establish
the malfunction criteria based on data from one or more representative
engine(s) and provide an engineering evaluation for establishing the
malfunction criteria for the remainder of the manufacturer's product
line.
(B) Where no failure or deterioration of a component used for the
cold start emission reduction strategy could result in an engine's
emissions exceeding the applicable emissions thresholds, the individual
component must be monitored for proper functional response while the
control strategy is active in accordance with the malfunction criteria
in paragraphs (i)(3)(ii) and (i)(3)(iii) of this section.
(iii) Cold start strategy monitoring conditions. The manufacturer
must define monitoring conditions for malfunctions identified in
paragraph (h)(4)(ii) of this section in accordance with paragraphs (c)
and (d) of this section.
(iv) Cold start strategy MIL activation and DTC storage. The MIL
must activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(5) Secondary air system monitoring.
(i) General. The OBD system on engines equipped with any form of
secondary air delivery system must monitor the proper functioning of
the secondary air delivery system including all air switching
valves(s). The individual electronic components (e.g., actuators,
valves, sensors) that are used in the secondary air system must be
monitored in accordance with the comprehensive component requirements
in paragraph (i)(3) of this section. For purposes of this paragraph
(h)(5), ``air flow'' is defined as the air flow delivered by the
secondary air system to the exhaust system. For engines using secondary
air systems with multiple air flow paths/distribution points, the air
flow to each bank (i.e., a group of cylinders that share a common
exhaust manifold, catalyst, and control sensor) must be monitored in
accordance with the malfunction criteria in paragraph (h)(5)(ii) of
this section. Also for purposes of this paragraph (h)(5), ``normal
operation'' is defined as the condition when the secondary air system
is activated during catalyst and/or engine warm-up following engine
start. ``Normal operation'' does not include the condition when the
secondary air system is turned on intrusively for the sole purpose of
monitoring.
(ii) Secondary air system malfunction criteria.
(A) Except as provided in paragraph (h)(5)(ii)(C) of this section,
the OBD system must detect a secondary air system malfunction prior to
a decrease from the manufacturer's specified air
[[Page 3305]]
flow during normal operation that would cause an engine's emissions to
exceed the emissions thresholds for ``other monitors'' as shown in
Table 2 of this paragraph (h).
(B) Except as provided in paragraph (h)(5)(ii)(C) of this section,
the OBD system must detect a secondary air system malfunction prior to
an increase from the manufacturer's specified air flow during normal
operation that would cause an engine's emissions to exceed the
emissions thresholds for ``other monitors'' as shown in Table 2 of this
paragraph (h).
(C) For engines in which no deterioration or failure of the
secondary air system would result in an engine's emissions exceeding
the applicable emissions thresholds, the OBD system must detect a
malfunction when no detectable amount of air flow is delivered by the
secondary air system during normal operation.
(iii) Secondary air system monitoring conditions. The manufacturer
must define monitoring conditions for malfunctions identified in
paragraph (h)(5)(ii) of this section in accordance with paragraphs (c)
and (d) of this section. For purposes of tracking and reporting as
required by paragraph (d)(1) of this section, all monitors used to
detect malfunctions identified in paragraph (h)(5)(ii) of this section
must be tracked separately but reported as a single set of values as
specified in paragraph (e)(1)(iii) of this section.
(iv) Secondary air system MIL activation and DTC storage. The MIL
must activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(6) Catalyst system monitoring.
(i) General. The OBD system must monitor the catalyst system for
proper conversion capability.
(ii) Catalyst system malfunction criteria. The OBD system must
detect a catalyst system malfunction when the catalyst system's
conversion capability decreases to the point that emissions exceed the
emissions thresholds for the catalyst system as shown in Table 2 of
this paragraph (h).
(iii) Catalyst system monitoring conditions. The manufacturer must
define monitoring conditions for malfunctions identified in paragraph
(h)(6)(ii) of this section in accordance with paragraphs (c) and (d) of
this section. For purposes of tracking and reporting as required by
paragraph (d)(1) of this section, all monitors used to detect
malfunctions identified in paragraph (h)(6)(ii) of this section must be
tracked separately but reported as a single set of values as specified
in paragraph (e)(1)(iii) of this section.
(iv) Catalyst system MIL activation and DTC storage.
(A) The MIL must activate and DTCs must be stored according to the
provisions of paragraph (b) of this section.
(B) The monitoring method for the catalyst system must be capable
of detecting when a catalyst DTC has been erased (except OBD system
self erasure), but the catalyst has not been replaced (e.g., catalyst
overtemperature histogram approaches are not acceptable).
(7) Evaporative system monitoring.
(i) General. The OBD system must verify purge flow from the
evaporative system and monitor the complete evaporative system,
excluding the tubing and connections between the purge valve and the
intake manifold, for vapor leaks to the atmosphere. Individual
components of the evaporative system (e.g., valves, sensors) must be
monitored in accordance with the comprehensive components requirements
in paragraph (i)(3) of this section.
(ii) Evaporative system malfunction criteria.
(A) Purge monitor. The OBD system must detect an evaporative system
malfunction when no purge flow from the evaporative system to the
engine can be detected by the OBD system.
(B) Leak monitor. The OBD system must detect an evaporative system
malfunction when the complete evaporative system contains a leak or
leaks that cumulatively are greater than or equal to a leak caused by a
0.150 inch diameter hole.
(C) The manufacturer may demonstrate that detection of a larger
hole is more appropriate than that specified in paragraph (h)(7)(ii)(B)
of this section. To do so, the manufacturer must demonstrate through
data and/or engineering analyses that holes smaller than the proposed
detection size would not result in evaporative or running loss
emissions that exceed 1.5 times the applicable evaporative emissions
standards. Upon such a demonstration, the proposed detection size could
be substituted for the requirement of paragraph (h)(7)(ii)(B) of this
section.
(iii) Evaporative system monitoring conditions.
(A) The manufacturer must define monitoring conditions for
malfunctions identified in paragraph (h)(7)(ii)(A) of this section in
accordance with paragraphs (c) and (d) of this section.
(B) The manufacturer must define monitoring conditions for
malfunctions identified in paragraph (h)(7)(ii)(B) of this section in
accordance with paragraphs (c) and (d) of this section. For purposes of
tracking and reporting as required by paragraph (d)(1) of this section,
all monitors used to detect malfunctions identified in paragraph
(h)(7)(ii)(B) of this section must be tracked separately but reported
as a single set of values as specified in paragraph (e)(1)(iii) of this
section.
(C) The manufacturer may disable or abort an evaporative system
monitor when the fuel tank level is over 85 percent of nominal tank
capacity or during a refueling event.
(D) The manufacturer may request Administrator approval to run the
evaporative system monitor during only those drive cycles characterized
as cold starts provided such a condition is needed to ensure reliable
monitoring. In making the request, the manufacturer must demonstrate
through data and/or engineering analyses that a reliable monitor can
only be run on drive cycles that begin with a specific set of cold
start criteria. A set of cold start criteria based solely on ambient
temperature exceeding engine coolant temperature will not be
acceptable.
(E) The OBD system may disable temporarily the evaporative purge
system to run an evaporative system leak monitor.
(iv) Evaporative system MIL activation and DTC storage.
(A) Except as provided for in paragraph (h)(7)(iv)(B) of this
section, the MIL must activate and DTCs must be stored according to the
provisions of paragraph (b) of this section.
(B) If the OBD system is capable of discerning that a system leak
is being caused by a missing or improperly secured gas cap, the OBD
system need not activate the MIL or store a DTC provided the vehicle is
equipped with an alternative indicator for notifying the operator of
the gas cap problem. The alternative indicator must be of sufficient
illumination and location to be readily visible under all lighting
conditions. If the vehicle is not equipped with such an alternative
indicator, the MIL must activate and a DTC be stored as required in
paragraph (h)(7)(iv)(A) of this section; however, these may be
deactivated and erased, respectively, if the OBD system determines that
the gas cap problem has been corrected and the MIL has not been
activated for any other malfunction. The Administrator may approve
other strategies that provide equivalent assurance that a vehicle
operator will be notified promptly of a missing or improperly secured
gas cap and that corrective action will be undertaken.
(8) Exhaust gas sensor monitoring.
(i) General.
(A) The OBD system must monitor for malfunctions the output signal,
[[Page 3306]]
response rate, and any other parameter that can affect emissions of all
primary (i.e., fuel control) exhaust gas sensors (e.g., oxygen, wide-
range air/fuel). Both the lean-to-rich and rich-to-lean response rates
must be monitored.
(B) The OBD system must also monitor all secondary exhaust gas
sensors (those used for secondary fuel trim control or as a monitoring
device) for proper output signal, activity, and response rate.
(C) For engines equipped with heated exhaust gas sensor, the OBD
system must monitor the heater for proper performance.
(ii) Primary exhaust gas sensor malfunction criteria.
(A) The OBD system must detect a malfunction prior to any failure
or deterioration of the exhaust gas sensor output voltage, resistance,
impedance, current, response rate, amplitude, offset, or other
characteristic(s) (including drift or bias corrected for by secondary
sensors) that would cause an engine's emissions to exceed the emissions
thresholds for ``other monitors'' as shown in Table 2 of this paragraph
(h).
(B) The OBD system must detect malfunctions of the exhaust gas
sensor caused by either a lack of circuit continuity or out-of-range
values.
(C) The OBD system must detect a malfunction of the exhaust gas
sensor when a sensor failure or deterioration causes the fuel system to
stop using that sensor as a feedback input (e.g., causes default or
open-loop operation).
(D) The OBD system must detect a malfunction of the exhaust gas
sensor when the sensor output voltage, resistance, impedance, current,
amplitude, activity, or other characteristics are no longer sufficient
for use as an OBD system monitoring device (e.g., for catalyst
monitoring).
(iii) Secondary exhaust gas sensor malfunction criteria.
(A) The OBD system must detect a malfunction prior to any failure
or deterioration of the exhaust gas sensor voltage, resistance,
impedance, current, response rate, amplitude, offset, or other
characteristic(s) that would cause an engine's emissions to exceed the
emissions thresholds for ``other monitors'' as shown in Table 2 of this
paragraph (h).
(B) The OBD system must detect malfunctions of the exhaust gas
sensor caused by a lack of circuit continuity.
(C) To the extent feasible, the OBD system must detect a
malfunction of the exhaust gas sensor when the sensor output voltage,
resistance, impedance, current, amplitude, activity, offset, or other
characteristics are no longer sufficient for use as an OBD system
monitoring device (e.g., for catalyst monitoring).
(D) The OBD system must detect malfunctions of the exhaust gas
sensor caused by out-of-range values.
(E) The OBD system must detect a malfunction of the exhaust gas
sensor when a sensor failure or deterioration causes the fuel system
(e.g., fuel control) to stop using that sensor as a feedback input
(e.g., causes default or open-loop operation).
(iv) Exhaust gas sensor heater malfunction criteria.
(A) The OBD system must detect a malfunction of the heater
performance when the current or voltage drop in the heater circuit is
no longer within the manufacturer's specified limits for normal
operation (i.e., within the criteria required to be met by the
component vendor for heater circuit performance at high mileage). Other
malfunction criteria for heater performance malfunctions may be used
upon demonstrating via data or engineering analyses that the monitoring
reliability and timeliness is equivalent to the stated criteria in this
paragraph (h)(8)(iv)(A).
(B) The OBD system must detect malfunctions of the heater circuit
including open or short circuits that conflict with the commanded state
of the heater (e.g., shorted to 12 Volts when commanded to 0 Volts
(ground)).
(v) Primary exhaust gas sensor monitoring conditions.
(A) The manufacturer must define monitoring conditions for
malfunctions identified in paragraphs (h)(8)(ii)(A) and (h)(8)(ii)(D)
of this section in accordance with paragraphs (c) and (d) of this
section. For purposes of tracking and reporting as required by
paragraph (d)(1) of this section, all monitors used to detect
malfunctions identified in paragraphs (h)(8)(ii)(A) and (h)(8)(ii)(D)
of this section must be tracked separately but reported as a single set
of values as specified in paragraph (e)(1)(iii) of this section.
(B) Except as provided for in paragraph (h)(8)(v)(C) of this
section, monitoring for malfunctions identified in paragraphs
(h)(8)(ii)(B) and (h)(8)(ii)(C) of this section must be conducted
continuously.
(C) The manufacturer may disable continuous primary exhaust gas
sensor monitoring when a primary exhaust gas sensor malfunction cannot
be distinguished from other effects (e.g., disable out-of-range low
monitoring during fuel cut conditions). To do so, the manufacturer must
demonstrate via data or engineering analyses that a properly
functioning sensor cannot be distinguished from a malfunctioning sensor
and that the disablement interval is limited only to that necessary for
avoiding false detection.
(vi) Secondary exhaust gas sensor monitoring conditions.
(A) The manufacturer must define monitoring conditions for
malfunctions identified in paragraphs (h)(8)(iii)(A) through
(h)(8)(iii)(C) of this section in accordance with paragraphs (c) and
(d) of this section.
(B) Except as provided for in paragraph (h)(8)(vi)(C) of this
section, monitoring for malfunctions identified in paragraphs
(h)(8)(iii)(D) and (h)(8)(iii)(E) of this section must be conducted
continuously.
(C) The manufacturer may disable continuous secondary exhaust gas
sensor monitoring when a secondary exhaust gas sensor malfunction
cannot be distinguished from other effects (e.g., disable out-of-range
low monitoring during fuel cut conditions). To do so, the manufacturer
must demonstrate via data or engineering analyses that a properly
functioning sensor cannot be distinguished from a malfunctioning sensor
and that the disablement interval is limited only to that necessary for
avoiding false detection.
(vii) Exhaust gas sensor heater monitoring conditions.
(A) The manufacturer must define monitoring conditions for
malfunctions identified in paragraph (h)(8)(iv)(A) of this section in
accordance with paragraphs (c) and (d) of this section.
(B) Monitoring for malfunctions identified in paragraph
(h)(8)(iv)(B) of this section must be conducted continuously.
(viii) Exhaust gas sensor MIL activation and DTC storage. The MIL
must activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(9) Variable valve timing (VVT) system monitoring.
(i) General. The OBD system must monitor the VVT system on engines
so equipped for target error and slow response malfunctions. The
individual electronic components (e.g., actuators, valves, sensors)
that are used in the VVT system must be monitored in accordance with
the comprehensive components requirements in paragraph (i)(3) of this
section.
(ii) VVT system malfunction criteria.
(A) VVT system target error. The OBD system must detect a
malfunction prior to any failure or deterioration in the capability of
the VVT system to achieve the commanded valve timing and/or control
within a crank angle and/or lift tolerance that would cause an engine's
emissions to exceed the emission
[[Page 3307]]
thresholds for ``other monitors'' as shown in Table 2 of this paragraph
(h).
(B) VVT slow response. The OBD system must detect a malfunction
prior to any failure or deterioration in the capability of the VVT
system to achieve the commanded valve timing and/or control within a
manufacturer-specified time that would cause an engine's emissions to
exceed the emission thresholds for ``other monitors'' as shown in Table
2 of this paragraph (h).
(C) For engines in which no failure or deterioration of the VVT
system could result in an engine's emissions exceeding the applicable
emissions thresholds of paragraphs (h)(9)(ii)(A) and (h)(9)(ii)(B) of
this paragraph (h), the OBD system must detect a malfunction of the VVT
system when proper functional response of the system to computer
commands does not occur.
(iii) VVT system monitoring conditions. Manufacturers must define
the monitoring conditions for VVT system malfunctions identified in
paragraph (h)(9)(ii) of this section in accordance with paragraphs (c)
and (d) of this section, with the exception that monitoring must occur
every time the monitoring conditions are met during the drive cycle
rather than once per drive cycle as required in paragraph (c)(2) of
this section. For purposes of tracking and reporting as required in
paragraph (d)(1) of this section, all monitors used to detect
malfunctions identified in paragraph (h)(9)(ii) of this section must be
tracked separately but reported as a single set of values as specified
in paragraph (e)(1)(iii) of this section.
(iv) VVT MIL activation and DTC storage. The MIL must activate and
DTCs must be stored according to the provisions of paragraph (b) of
this section.
(i) OBD monitoring requirements for all engines.
(1) Engine cooling system monitoring.
(i) General.
(A) The OBD system must monitor the thermostat on engines so
equipped for proper operation.
(B) The OBD system must monitor the engine coolant temperature
(ECT) sensor for electrical circuit continuity, out-of-range values,
and rationality malfunctions.
(C) For engines that use a system other than the cooling system and
ECT sensor (e.g., oil temperature, cylinder head temperature) to
determine engine operating temperature for emission control purposes
(e.g., to modify spark or fuel injection timing or quantity), the
manufacturer may forego cooling system monitoring and instead monitor
the components or systems used in their approach. To do so, the
manufacturer must to submit data and/or engineering analyses that
demonstrate that their monitoring plan is as reliable and effective as
the monitoring required in this paragraph (i)(1).
(ii) Malfunction criteria for the thermostat.
(A) The OBD system must detect a thermostat malfunction if, within
the manufacturer specified time interval following engine start, any of
the following conditions occur: the coolant temperature does not reach
the highest temperature required by the OBD system to enable other
diagnostics; and, the coolant temperature does not reach a warmed-up
temperature within 20 degrees Fahrenheit of the manufacturer's nominal
thermostat regulating temperature. For the second of these two
conditions, the manufacturer may use a lower temperature for this
criterion provided the manufacturer can demonstrate that the fuel,
spark timing, and/or other coolant temperature-based modification to
the engine control strategies would not cause an emissions increase
greater than or equal to 50 percent of any of the applicable emissions
standards.
(B) The manufacturer may use alternative malfunction criteria to
those of paragraph (i)(1)(ii)(A) of this section and/or alternative
monitoring conditions to those of paragraph (i)(1)(iv) of this section
that are a function of temperature at engine start on engines that do
not reach the temperatures specified in the malfunction criteria when
the thermostat is functioning properly. To do so, the manufacturer is
required to submit data and/or engineering analyses that demonstrate
that a properly operating system does not reach the specified
temperatures and that the possibility is minimized for cooling system
malfunctions to go undetected thus disabling other OBD monitors.
(C) The manufacturer may request Administrator approval to forego
monitoring of the thermostat if the manufacturer can demonstrate that a
malfunctioning thermostat cannot cause a measurable increase in
emissions during any reasonable driving condition nor cause any
disablement of other OBD monitors.
(iii) Malfunction criteria for the ECT sensor.
(A) Circuit integrity. The OBD system must detect malfunctions of
the ECT sensor related to a lack of circuit continuity or out-of-range
values.
(B) Time to reach closed-loop/feedback enable temperature. The OBD
system must detect if, within the manufacturer specified time interval
following engine start, the ECT sensor does not achieve the highest
stabilized minimum temperature that is needed to initiate closed-loop/
feedback control of all affected emission control systems (e.g., fuel
system, EGR system). The manufacturer specified time interval must be a
function of the engine coolant temperature and/or intake air
temperature at startup. The manufacturer time interval must be
supported by data and/or engineering analyses demonstrating that it
provides robust monitoring and minimizes the likelihood of other OBD
monitors being disabled. The manufacturer may forego the requirements
of this paragraph (i)(1)(iii)(B) provided the manufacturer does not use
engine coolant temperature or the ECT sensor to enable closed-loop/
feedback control of any emission control systems.
(C) Stuck in range below the highest minimum enable temperature. To
the extent feasible when using all available information, the OBD
system must detect a malfunction if the ECT sensor inappropriately
indicates a temperature below the highest minimum enable temperature
required by the OBD system to enable other monitors (e.g., an OBD
system that requires ECT to be greater than 140 degrees Fahrenheit to
enable a diagnostic must detect malfunctions that cause the ECT sensor
to inappropriately indicate a temperature below 140 degrees
Fahrenheit). The manufacturer may forego this requirement for
temperature regions in which the monitors required under paragraphs
(i)(1)(ii) or (i)(1)(iii)(B) of this section will detect ECT sensor
malfunctions as defined in this paragraph (i)(1)(iii)(C).
(D) Stuck in range above the lowest maximum enable temperature. The
OBD system must detect a malfunction if the ECT sensor inappropriately
indicates a temperature above the lowest maximum enable temperature
required by the OBD system to enable other monitors (e.g., an OBD
system that requires an engine coolant temperature less than 90 degrees
Fahrenheit at startup prior to enabling an OBD monitor must detect
malfunctions that cause the ECT sensor to indicate inappropriately a
temperature above 90 degrees Fahrenheit). The manufacturer may forego
this requirement within temperature regions in which the monitors
required under paragraphs (i)(1)(ii), (i)(1)(iii)(B), and
(i)(1)(iii)(C) of this section will detect ECT sensor malfunctions as
defined in this paragraph (i)(1)(iii)(D) or in which the MIL will be
activated according to the provisions of paragraph (b)(2)(v) of this
[[Page 3308]]
section. The manufacturer may also forego this monitoring within
temperature regions where a temperature gauge on the instrument panel
indicates a temperature in the ``red zone'' (engine overheating zone)
and displays the same temperature information as used by the OBD
system.
(iv) Monitoring conditions for the thermostat.
(A) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraph (i)(1)(ii)(A) of this section in
accordance with paragraph (c) of this section. Additionally, except as
provided for in paragraphs (i)(1)(iv)(B) and (i)(1)(iv)(C) of this
section, monitoring for malfunctions identified in paragraph
(i)(1)(ii)(A) of this section must be conducted once per drive cycle on
every drive cycle in which the ECT sensor indicates, at engine start, a
temperature lower than the temperature established as the malfunction
criteria in paragraph (i)(1)(ii)(A) of this section.
(B) The manufacturer may disable thermostat monitoring at ambient
engine start temperatures below 20 degrees Fahrenheit.
(C) The manufacturer may request Administrator approval to suspend
or disable thermostat monitoring if the engine is subjected to
conditions that could lead to false diagnosis. To do so, the
manufacturer must submit data and/or engineering analyses that
demonstrate that the suspension or disablement is necessary. In
general, the manufacturer will not be allowed to suspend or disable the
thermostat monitor on engine starts where the engine coolant
temperature at engine start is more than 35 degrees Fahrenheit lower
than the thermostat malfunction threshold temperature determined under
paragraph (i)(1)(ii)(A) of this paragraph (i)(1).
(v) Monitoring conditions for the ECT sensor.
(A) Except as provided for in paragraph (i)(1)(v)(E) of this
section, the OBD system must monitor continuously for malfunctions
identified in paragraph (i)(1)(iii)(A) of this section (i.e., circuit
integrity and out-of-range).
(B) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraph (i)(1)(iii)(B) of this section in
accordance with paragraph (c) of this section. Additionally, except as
provided for in paragraph (i)(1)(v)(D) of this section, monitoring for
malfunctions identified in paragraph (i)(1)(iii)(B) of this section
must be conducted once per drive cycle on every drive cycle in which
the ECT sensor indicates a temperature lower than the closed-loop
enable temperature at engine start (i.e., all engine start temperatures
greater than the ECT sensor out-of-range low temperature and less than
the closed-loop enable temperature).
(C) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraphs (i)(1)(iii)(C) and (i)(1)(iii)(D)
of this section in accordance with paragraphs (c) and (d) of this
section.
(D) The manufacturer may suspend or delay the monitor for the time
to reach closed-loop enable temperature if the engine is subjected to
conditions that could lead to false diagnosis (e.g., vehicle operation
at idle for more than 50 to 75 percent of the warm-up time).
(E) The manufacturer may request Administrator approval to disable
continuous ECT sensor monitoring when an ECT sensor malfunction cannot
be distinguished from other effects. To do so, the manufacturer must
submit data and/or engineering analyses that demonstrate a properly
functioning sensor cannot be distinguished from a malfunctioning sensor
and that the disablement interval is limited only to that necessary for
avoiding false detection.
(vi) Engine cooling system MIL activation and DTC storage. The MIL
must activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(2) Crankcase ventilation (CV) system monitoring.
(i) General. The OBD system must monitor the CV system on engines
so equipped for system integrity. Engines not required to be equipped
with CV systems are exempt from monitoring the CV system. For diesel
engines, the manufacturer must submit a plan for Administrator prior to
OBD certification. That plan must include descriptions of the
monitoring strategy, malfunction criteria, and monitoring conditions
for CV system monitoring. The plan must demonstrate that the CV system
monitor is of equivalent effectiveness, to the extent feasible, to the
malfunction criteria and the monitoring conditions of this paragraph
(i)(2).
(ii) Crankcase ventilation system malfunction criteria.
(A) For the purposes of this paragraph (i)(2), ``CV system'' is
defined as any form of crankcase ventilation system, regardless of
whether it utilizes positive pressure. ``CV valve'' is defined as any
form of valve or orifice used to restrict or control crankcase vapor
flow. Further, any additional external CV system tubing or hoses used
to equalize crankcase pressure or to provide a ventilation path between
various areas of the engine (e.g., crankcase and valve cover) are
considered part of the CV system ``between the crankcase and the CV
valve'' and subject to the malfunction criteria in paragraph
(i)(2)(ii)(B) of this section.
(B) Except as provided for in paragraphs (i)(2)(ii)(C) through
(i)(2)(ii)(E) of this section, the OBD system must detect a malfunction
of the CV system when a disconnection of the system occurs between
either the crankcase and the CV valve, or between the CV valve and the
intake manifold.
(C) The manufacturer may forego monitoring for a disconnection
between the crankcase and the CV valve provided the CV system is
designed such that the CV valve is fastened directly to the crankcase
such that it is significantly more difficult to remove the CV valve
from the crankcase than to disconnect the line between the CV valve and
the intake manifold (taking aging effects into consideration). To do
so, the manufacturer must be able to provide data and/or an engineering
evaluation demonstrating that the CV system is so designed.
(D) The manufacturer may forego monitoring for a disconnection
between the crankcase and the CV valve provided the CV system is
designed such that it uses tubing connections between the CV valve and
the crankcase that are: resistant to deterioration or accidental
disconnection; significantly more difficult to disconnect than is the
line between the CV valve and the intake manifold; and, not subject to
disconnection per the manufacturer's repair procedures for any non-CV
system repair. To do so, the manufacturer must be able to provide data
and/or engineering evaluation demonstrating that the CV system is so
designed.
(E) The manufacturer may forego monitoring for a disconnection
between the CV valve and the intake manifold provided the CV system is
designed such that any disconnection either causes the engine to stall
immediately during idle operation, or is unlikely to occur due to a CV
system design that is integral to the induction system (e.g., machined
passages rather than tubing or hoses). To do so, the manufacturer must
be able to provide data and/or an engineering evaluation demonstrating
that the CV system is so designed.
(iii) Crankcase ventilation system monitoring conditions. The
manufacturer must define the monitoring conditions for malfunctions
identified in paragraph (i)(2) of this section in accordance with
paragraphs (c) and (d) of this section.
[[Page 3309]]
(iv) Crankcase ventilation system MIL activation and DTC storage.
The MIL must activate and DTCs must be stored according to the
provisions of paragraph (b) of this section. The stored DTC need not
identify specifically the CV system (e.g., a DTC for idle speed control
or fuel system monitoring can be stored) if the manufacturer can
demonstrate that additional monitoring hardware is necessary to make
such an identification and provided the manufacturer's diagnostic and
repair procedures for the detected malfunction include directions to
check the integrity of the CV system.
(3) Comprehensive component monitoring.
(i) General. Except as provided for in paragraph (i)(4) of this
section, the OBD system must detect a malfunction of any electronic
engine component or system not otherwise described in paragraphs (g),
(h), (i)(1), and (i)(2) of this section that either provides input to
(directly or indirectly, such components may include the crank angle
sensor, knock sensor, throttle position sensor, cam position sensor,
intake air temperature sensor, boost pressure sensor, manifold pressure
sensor, mass air flow sensor, exhaust temperature sensor, exhaust
pressure sensor, fuel pressure sensor, fuel composition sensor of a
flexible fuel vehicle, etc.) or receives commands from (such components
or systems may include the idle speed control system, glow plug system,
variable length intake manifold runner systems, supercharger or
turbocharger electronic components, heated fuel preparation systems,
the wait-to-start lamp on diesel applications, the MIL, etc.) the
onboard computer(s) and meets either of the criteria described in
paragraphs (i)(3)(i)(A) and/or (i)(3)(i)(B) of this section. Note that,
for the purposes of this paragraph (i)(3), ``electronic engine
component or system'' does not include components that are driven by
the engine and are not related to the control of the fueling, air
handling, or emissions of the engine (e.g., power take-off (PTO)
components, air conditioning system components, and power steering
components).
(A) It can affect emissions during any reasonable in-use driving
condition. The manufacturer must be able to provide emission data
showing that the component or system, when malfunctioning and installed
on a suitable test engine, does not have an emission effect.
(B) It is used as part of the monitoring strategy for any other
monitored system or component.
(ii) Comprehensive component malfunction criteria for input
components.
(A) The OBD system must detect malfunctions of input components
caused by a lack of circuit continuity and out-of-range values. In
addition, where feasible, rationality checks must also be done and
shall verify that a sensor output is neither inappropriately high nor
inappropriately low (i.e., ``two-sided'' monitoring).
(B) To the extent feasible, the OBD system must separately detect
and store different DTCs that distinguish rationality malfunctions from
lack of circuit continuity and out-of-range malfunctions. For lack of
circuit continuity and out-of-range malfunctions, the OBD system must,
to the extent feasible, separately detect and store different DTCs for
each distinct malfunction (e.g., out-of-range low, out-of-range high,
open circuit). The OBD system is not required to store separate DTCs
for lack of circuit continuity malfunctions that cannot be
distinguished from other out-of-range circuit malfunctions.
(C) For input components that are used to activate alternative
strategies that can affect emissions (e.g., AECDs, engine shutdown
systems), the OBD system must conduct rationality checks to detect
malfunctions that cause the system to activate erroneously or
deactivate the alternative strategy. To the extent feasible when using
all available information, the rationality check must detect a
malfunction if the input component inappropriately indicates a value
that activates or deactivates the alternative strategy. For example,
for an alternative strategy that activates when the intake air
temperature is greater than 120 degrees Fahrenheit, the OBD system must
detect malfunctions that cause the intake air temperature sensor to
indicate inappropriately a temperature above 120 degrees Fahrenheit.
(D) For engines that require precise alignment between the camshaft
and the crankshaft, the OBD system must monitor the crankshaft position
sensor(s) and camshaft position sensor(s) to verify proper alignment
between the camshaft and crankshaft in addition to monitoring the
sensors for circuit continuity and proper rationality. Proper alignment
monitoring between a camshaft and a crankshaft is required only in
cases where both are equipped with position sensors. For engines
equipped with VVT systems and a timing belt or chain, the OBD system
must detect a malfunction if the alignment between the camshaft and
crankshaft is off by one or more cam/crank sprocket cogs (e.g., the
timing belt/chain has slipped by one or more teeth/cogs). If a
manufacturer demonstrates that a single tooth/cog misalignment cannot
cause a measurable increase in emissions during any reasonable driving
condition, the OBD system must detect a malfunction when the minimum
number of teeth/cogs misalignment has occurred that does cause a
measurable emission increase.
(iii) Comprehensive component malfunction criteria for output
components/systems.
(A) The OBD system must detect a malfunction of an output
component/system when proper functional response does not occur in
response to computer commands. If such a functional check is not
feasible, the OBD system must detect malfunctions of output components/
systems caused by a lack of circuit continuity or circuit malfunction
(e.g., short to ground or high voltage). For output component lack of
circuit continuity malfunctions and circuit malfunctions, the OBD
system is not required to store different DTCs for each distinct
malfunction (e.g., open circuit, shorted low). Manufacturers are not
required to activate an output component/system when it would not
normally be active for the sole purpose of performing a functional
check of it as required in this paragraph (i)(3).
(B) For gasoline engines, the idle control system must be monitored
for proper functional response to computer commands. For gasoline
engines using monitoring strategies based on deviation from target idle
speed, a malfunction must be detected when either of the following
conditions occurs: the idle speed control system cannot achieve the
target idle speed within 200 revolutions per minute (rpm) above the
target speed or 100 rpm below the target speed; or, the idle speed
control system cannot achieve the target idle speed within the smallest
engine speed tolerance range required by the OBD system to enable any
other monitors. Regarding the former of these conditions, the
manufacturer may use larger engine speed tolerances. To do so, the
manufacturer must be able to provide data and/or engineering analyses
that demonstrate that the tolerances can be exceeded without a
malfunction being present.
(C) For diesel engines, the idle control system must be monitored
for proper functional response to computer commands. For diesel
engines, a malfunction must be detected when either of the following
conditions occurs: the idle fuel control system cannot achieve the
target idle speed or fuel injection quantity within 50
percent of the manufacturer-specified fuel quantity and engine speed
[[Page 3310]]
tolerances; or, the idle fuel control system cannot achieve the target
idle speed or fueling quantity within the smallest engine speed or
fueling quantity tolerance range required by the OBD system to enable
any other monitors.
(D) Glow plugs/intake air heater systems must be monitored for
proper functional response to computer commands and for circuit
continuity malfunctions. The glow plug/intake air heater circuit(s)
must be monitored for proper current and voltage drop. The manufacturer
may use other monitoring strategies but must be able to provide data
and/or engineering analyses that demonstrate reliable and timely
detection of malfunctions. The OBD system must also detect a
malfunction when a single glow plug no longer operates within the
manufacturer's specified limits for normal operation. If a manufacturer
can demonstrate that a single glow plug malfunction cannot cause a
measurable increase in emissions during any reasonable driving
condition, the OBD system must instead detect a malfunction when the
number of glow plugs needed to cause an emission increase is
malfunctioning. To the extent feasible, the stored DTC must identify
the specific malfunctioning glow plug(s).
(E) The wait-to-start lamp circuit and the MIL circuit must be
monitored for malfunctions that cause either lamp to fail to activate
when commanded to do so (e.g., burned out bulb).
(iv) Monitoring conditions for input components.
(A) The OBD system must monitor input components continuously for
out-of-range values and circuit continuity. The manufacturer may
disable continuous monitoring for circuit continuity and out-of-range
values when a malfunction cannot be distinguished from other effects.
To do so, the manufacturer must be able to provide data and/or
engineering analyses that demonstrate that a properly functioning input
component cannot be distinguished from a malfunctioning input component
and that the disablement interval is limited only to that necessary for
avoiding false malfunction detection.
(B) For input component rationality checks (where applicable), the
manufacturer must define the monitoring conditions for detecting
malfunctions in accordance with paragraphs (c) and (d) of this section,
with the exception that rationality checks must occur every time the
monitoring conditions are met during the drive cycle rather than once
per drive cycle as required in paragraph (c)(2) of this section.
(v) Monitoring conditions for output components/systems.
(A) The OBD system must monitor output components/systems
continuously for circuit continuity and circuit malfunctions. The
manufacturer may disable continuous monitoring for circuit continuity
and circuit malfunctions when a malfunction cannot be distinguished
from other effects. To do so, the manufacturer must be able to provide
data and/or engineering analyses that demonstrate that a properly
functioning output component/system cannot be distinguished from a
malfunctioning one and that the disablement interval is limited only to
that necessary for avoiding false malfunction detection.
(B) For output component/system functional checks, the manufacturer
must define the monitoring conditions for detecting malfunctions in
accordance with paragraphs (c) and (d) of this section. Specifically
for the idle control system, the manufacturer must define the
monitoring conditions for detecting malfunctions in accordance with
paragraphs (c) and (d) of this section, with the exception that
functional checks must occur every time the monitoring conditions are
met during the drive cycle rather than once per drive cycle as required
in paragraph (c)(2) of this section.
(vi) Comprehensive component MIL activation and DTC storage.
(A) Except as provided for in paragraphs (i)(3)(vi)(B) and
(i)(3)(vi)(C) of this section, the MIL must activate and DTCs must be
stored according to the provisions of paragraph (b) of this section.
(B) The MIL need not be activated in conjunction with storing a
MIL-on DTC for any comprehensive component if: the component or system,
when malfunctioning, could not cause engine emissions to increase by 15
percent or more of the applicable FTP standard during any reasonable
driving condition; or, the component or system is not used as part of
the monitoring strategy for any other system or component that is
required to be monitored.
(C) The MIL need not be activated if a malfunction has been
detected in the MIL circuit that prevents the MIL from activating
(e.g., burned out bulb or light-emitting diode, LED). Nonetheless, the
electronic MIL status (see paragraph (k)(4)(ii) of this section) must
be reported as MIL commanded-on and a MIL-on DTC must be stored.
(4) Other emission control system monitoring.
(i) General. For other emission control systems that are either not
addressed in paragraphs (g) through (i)(3) of this section (e.g.,
hydrocarbon traps, homogeneous charge compression ignition control
systems), or addressed in paragraph (i)(3) of this section but not
corrected or compensated for by an adaptive control system (e.g., swirl
control valves), the manufacturer must submit a plan for Administrator
approval of the monitoring strategy, malfunction criteria, and
monitoring conditions prior to introduction on a production engine. The
plan must demonstrate the effectiveness of the monitoring strategy, the
malfunction criteria used, the monitoring conditions required by the
monitor, and, if applicable, the determination that the requirements of
paragraph (i)(4)(ii) of this section are satisfied.
(ii) For engines that use emission control systems that alter
intake air flow or cylinder charge characteristics by actuating
valve(s), flap(s), etc., in the intake air delivery system (e.g., swirl
control valve systems), the manufacturer, in addition to meeting the
requirements of paragraph (i)(4)(i) of this section, may elect to have
the OBD system monitor the shaft to which all valves in one intake bank
are physically attached rather than performing a functional check of
the intake air flow, cylinder charge, or individual valve(s)/flap(s).
For non-metal shafts or segmented shafts, the monitor must verify all
shaft segments for proper functional response (e.g., by verifying that
the segment or portion of the shaft farthest from the actuator
functions properly). For systems that have more than one shaft to
operate valves in multiple intake banks, the manufacturer is not
required to add more than one set of detection hardware (e.g., sensor,
switch) per intake bank to meet this requirement.
(5) Exceptions to OBD monitoring requirements.
(i) The Administrator may revise the PM filtering performance
malfunction criteria for DPFs to exclude detection of specific failure
modes such as partially melted substrates, if the most reliable
monitoring method developed requires it.
(ii) The manufacturer may disable an OBD system monitor at ambient
engine start temperatures below 20 degrees Fahrenheit (low ambient
temperature conditions may be determined based on intake air or engine
coolant temperature at engine start) or at elevations higher than 8,000
feet above sea level. To do so, the manufacturer must submit data and/
or engineering analyses that demonstrate that monitoring is
[[Page 3311]]
unreliable during the disable conditions. A manufacturer may request
that an OBD system monitor be disabled at other ambient engine start
temperatures by submitting data and/or engineering analyses
demonstrating that misdiagnosis would occur at the given ambient
temperatures due to their effect on the component itself (e.g.,
component freezing).
(iii) The manufacturer may disable an OBD system monitor when the
fuel level is 15 percent or less of the nominal fuel tank capacity for
those monitors that can be affected by low fuel level or running out of
fuel (e.g., misfire detection). To do so, the manufacturer must submit
data and/or engineering analyses that demonstrate that monitoring at
the given fuel levels is unreliable, and that the OBD system is still
able to detect a malfunction if the component(s) used to determine fuel
level indicates erroneously a fuel level that causes the disablement.
(iv) The manufacturer may disable OBD monitors that can be affected
by engine battery or system voltage levels.
(A) For an OBD monitor affected by low vehicle battery or system
voltages, manufacturers may disable monitoring when the battery or
system voltage is below 11.0 Volts. The manufacturer may use a voltage
threshold higher than 11.0 Volts to disable monitors but must submit
data and/or engineering analyses that demonstrate that monitoring at
those voltages is unreliable and that either operation of a vehicle
below the disablement criteria for extended periods of time is unlikely
or the OBD system monitors the battery or system voltage and will
detect a malfunction at the voltage used to disable other monitors.
(B) For an OBD monitor affected by high engine battery or system
voltages, the manufacturer may disable monitoring when the battery or
system voltage exceeds a manufacturer-defined voltage. To do so, the
manufacturer must submit data and/or engineering analyses that
demonstrate that monitoring above the manufacturer-defined voltage is
unreliable and that either the electrical charging system/alternator
warning light will be activated (or voltage gauge would be in the ``red
zone'') or the OBD system monitors the battery or system voltage and
will detect a malfunction at the voltage used to disable other
monitors.
(v) The manufacturer may also disable affected OBD monitors in
systems designed to accommodate the installation of power take off
(PTO) units provided monitors are disabled only while the PTO unit is
active and the OBD readiness status (see paragraph (k)(4)(i) of this
section) is cleared by the onboard computer (i.e., all monitors set to
indicate ``not complete'' or ``not ready'') while the PTO unit is
activated. If monitors are so disabled and when the disablement ends,
the readiness status may be restored to its state prior to PTO
activation.
(6) Feedback control system monitoring. If the engine is equipped
with feedback control of any of the systems covered in paragraphs (g),
(h) and (i) of this section, then the OBD system must detect as
malfunctions the conditions specified in this paragraph (i)(6) for each
of the individual feedback controls.
(i) The OBD system must detect when the system fails to begin
feedback control within a manufacturer specified time interval.
(ii) When any malfunction or deterioration causes open loop or
limp-home operation.
(iii) When feedback control has used up all of the adjustment
allowed by the manufacturer.
(iv) A manufacturer may temporarily disable monitoring for
malfunctions specified in paragraph (i)(6)(iii) of this section during
conditions that the specific monitor cannot distinguish robustly
between a malfunctioning system and a properly operating system. To do
so, the manufacturer is required to submit data and/or engineering
analyses demonstrating that the individual feedback control system,
when operating as designed on an engine with all emission controls
working properly, routinely operates during these conditions while
having used up all of the adjustment allowed by the manufacturer. In
lieu of detecting, with a system specific monitor, the malfunctions
specified in paragraphs (i)(6)(i) and (i)(6)(ii) of this section the
OBD system may monitor the individual parameters or components that are
used as inputs for individual feedback control systems provided that
the monitors detect all malfunctions that meet the criteria of
paragraphs (i)(6)(i) and (i)(6)(ii) of this section.
(a) Production evaluation testing.
(1) [Reserved.]
(2) Verification of monitoring requirements.
(i) Within either the first six months of the start of engine
production or the first three months of the start of vehicle
production, whichever is later, the manufacturer must conduct a
complete evaluation of the OBD system of one or more production
vehicles (test vehicles) and submit the results of the evaluation to
the Administrator.
(ii) Selection of test vehicles.
(A) For each engine selected for monitoring system demonstration in
paragraph (l) of this section, the manufacturer must evaluate one
production vehicle equipped with an engine from the same engine family
and rating as the demonstration engine. The vehicle selection must be
approved by the Administrator.
(B) If the manufacturer is required to test more than one test
vehicle, the manufacturer may test an engine in lieu of a vehicle for
all but one of the required test vehicles.
(C) The requirement for submittal of data from one or more of the
test vehicles may be waived if data have been submitted previously for
all of the engine ratings and variants.
(iii) Evaluation requirements.
(A) The evaluation must demonstrate the ability of the OBD system
on the selected test vehicle to detect a malfunction, activate the MIL,
and, where applicable, store an appropriate DTC readable by a scan tool
when a malfunction is present and the monitoring conditions have been
satisfied for each individual monitor required by this section.
(B) The evaluation must verify that the malfunction of any
component used to enable another OBD monitor but that does not itself
result in MIL activation (e.g., fuel level sensor) will not inhibit the
ability of other OBD monitors to detect malfunctions properly.
(C) The evaluation must verify that the software used to track the
numerator and denominator for the purpose of determining in-use
monitoring frequency increments as required by paragraph (d)(2) of this
section.
(D) Malfunctions may be implanted mechanically or simulated
electronically, but internal onboard computer hardware or software
changes shall not be used to simulate malfunctions. For monitors that
are required to indicate a malfunction before emissions exceed an
emission threshold, manufacturers are not required to use
malfunctioning components/systems set exactly at their malfunction
criteria limits. Emission testing is not required to confirm that the
malfunction is detected before the appropriate emission thresholds are
exceeded.
(E) The manufacturer must submit a proposed test plan for approval
prior to performing evaluation testing. The test plan must identify the
method used to induce a malfunction for each monitor.
(F) If the demonstration of a specific monitor cannot be reasonably
performed without causing physical damage to the test vehicle (e.g.,
onboard computer internal circuit malfunctions), the
[[Page 3312]]
manufacturer may omit the specific demonstration.
(G) For evaluation of test vehicles selected in accordance with
paragraph (j)(2)(ii) of this section, the manufacturer is not required
to demonstrate monitors that were demonstrated prior to certification
as required in paragraph (l) of this section.
(iv) The manufacturer must submit a report of the results of all
testing conducted as required by paragraph (j)(2) of this section. The
report must identify the method used to induce a malfunction in each
monitor, the MIL activation status, and the DTC(s) stored.
(3) Verification of in-use monitoring performance ratios.
(i) The manufacturer must collect and report in-use monitoring
performance data representative of production vehicles (i.e., engine
rating and chassis application combination). The manufacturer must
collect and report the data to the Administrator within 12 months after
the first production vehicle was first introduced into commerce.
(ii) The manufacturer must separate production vehicles into the
monitoring performance groups and submit data that represents each of
these groups. The groups shall be based on the following criteria:
(A) Emission control system architecture. All engines that use the
same or similar emissions control system architecture (e.g., EGR with
DPF and SCR; EGR with DPF and NOX adsorber; EGR with DPF-
only) and associated monitoring system would be in the same emission
architecture category.
(B) Vehicle application type. Within an emission architecture
category, engines shall be separated into one of three vehicle
application types: engines intended primarily for line-haul chassis
applications, engines intended primarily for urban delivery chassis
applications, and all other engines.
(iii) The manufacturer may use an alternative grouping method to
collect representative data. To do so, the manufacturer must show that
the alternative groups include production vehicles using similar
emission controls, OBD strategies, monitoring condition calibrations,
and vehicle application driving/usage patterns such that they are
expected to have similar in-use monitoring performance. The
manufacturer will still be required to submit one set of data for each
of the alternative groups.
(iv) For each monitoring performance group, the data must include
all of the in-use performance tracking data (i.e., all numerators,
denominators, the general denominator, and the ignition cycle counter),
the date the data were collected, the odometer reading, the VIN, and
the calibration ID.
(v) The manufacturer must submit a plan to the Administrator that
details the types of production vehicles in each monitoring performance
group, the number of vehicles per group to be sampled, the sampling
method, the timeline to collect the data, and the reporting format. The
plan must provide for effective collection of data from, at least, 15
vehicles per monitoring performance group and provide for data that
represent a broad range of temperature conditions. The plan shall not,
by design, exclude or include specific vehicles in an attempt to
collect data only from vehicles expected to have the highest in-use
performance ratios.
(vi) The 12 month deadline for reporting may be extended to 18
months if the manufacturer can show that the delay is justified. In
such a case, an interim report of progress to date must be submitted
within the 12 month deadline.
(k) Standardization requirements.
(1) Reference materials. The OBD system must conform with the
following Society of Automotive Engineers (SAE) standards and/or the
following International Standards Organization (ISO) standards. The
following documents are incorporated by reference, see Sec. 86.1:
(i) SAE material. Copies of these materials may be obtained from
the Society of Automotive Engineers, Inc., 400 Commonwealth Drive,
Warrendale, PA 15096-0001.
(A) SAE J1930 ``Electrical/Electronic Systems Diagnostic Terms,
Definitions, Abbreviations, and Acronyms--Equivalent to ISO/TR 15031-
2:April 30, 2002,'' April 2002.
(B) SAE J1939 ``Recommended Practice for a Serial Control and
Communications Vehicle Network'' and the associated subparts included
in SAE HS-1939, ``Truck and Bus Control and Communications Network
Standards Manual,'' 2006 Edition.
(C) [Reserved.]
(D) SAE J1978 ``OBD II Scan Tool--Equivalent to ISO/DIS 15031-4:
December 14, 2001,'' April 2002.
(E) SAE J1979 ``E/E Diagnostic Test Modes--Equivalent to ISO/DIS
15031-5:April 30, 2002,'' April 2002.
(F) SAE J2012 ``Diagnostic Trouble Code Definitions--Equivalent to
ISO/DIS 15031-6:April 30, 2002,'' April 2002.
(G) SAE J2403 ``Medium/Heavy-Duty E/E Systems Diagnosis
Nomenclature,'' August 2004.
(H) SAE J2534 ``Recommended Practice for Pass-Thru Vehicle
Reprogramming,'' February 2002.
(ii) ISO materials. Copies of these materials may be obtained from
the International Organization for Standardization, Case Postale 56,
CH-1211 Geneva 20, Switzerland.
(A) ISO 15765-4:2001 ``Road Vehicles-Diagnostics on Controller Area
Network (CAN)--Part 4: Requirements for emission-related systems,''
December 2001.
(2) The manufacturer defined data link connector must be accessible
to a trained service technician.
(3) [Reserved.]
(4) Required emission related functions. The following functions
must be implemented and must be accessible by, at a minimum, a
manufacturer scan tool:
(i) Ready status. The OBD system must indicate ``complete'' or
``not complete'' for each of the installed monitored components and
systems identified in paragraphs (g), (h) with the exception of (h)(4),
and (i)(3) of this section. All components or systems identified in
paragraphs (h)(1), (h)(2), or (i)(3) of this section that are monitored
continuously must always indicate ``complete.'' Components or systems
that are not subject to being monitored continuously must immediately
indicate ``complete'' upon the respective monitor(s) being executed
fully and determining that the component or system is not
malfunctioning. A component or system must also indicate ``complete''
if, after the requisite number of decisions necessary for determining
MIL status has been executed fully, the monitor indicates a malfunction
of the component or system. The status for each of the monitored
components or systems must indicate ``not complete'' whenever
diagnostic memory has been cleared or erased by a means other than that
allowed in paragraph (b) of this section. Normal vehicle shut down
(i.e., key-off/engine-off) shall not cause the status to indicate ``not
complete.''
(A) The manufacturer may request that the ready status for a
monitor be set to indicate ``complete'' without the monitor having
completed if monitoring is disabled for a multiple number of drive
cycles due to the continued presence of extreme operating conditions
(e.g., cold ambient temperatures, high altitudes). Any such request
must specify the conditions for monitoring system disablement and the
number of drive cycles that would pass without monitor completion
before ready status would be indicated as ``complete.''
[[Page 3313]]
(B) For the evaporative system monitor, the ready status must be
set in accordance with this paragraph (k)(4)(i) when both the
functional check of the purge valve and, if applicable, the leak
detection monitor of the hole size specified in paragraph (h)(7)(ii)(B)
of this section indicate that they are complete.
(C) If the manufacturer elects to indicate ready status through the
MIL in the key-on/engine-off position as provided for in paragraph
(b)(1)(iii) of this section, the ready status must be indicated in the
following manner: If the ready status for all monitored components or
systems is ``complete,'' the MIL shall remain continuously activated in
the key-on/engine-off position for at least 10-20 seconds. If the ready
status for one or more of the monitored components or systems is ``not
complete,'' after at least 5 seconds of operation in the key-on/engine-
off position with the MIL activated continuously, the MIL shall blink
once per second for 5-10 seconds. The data stream value for MIL status
as required in paragraph (k)(4)(ii) of this section must indicate
``commanded off'' during this sequence unless the MIL has also been
``commanded on'' for a detected malfunction.
(ii) Data stream. The following signals must be made available on
demand through the data link connector. The actual signal value must
always be used instead of a limp home value.
(A) For gasoline engines.
(1) Calculated load value, engine coolant temperature, engine
speed, vehicle speed, and time elapsed since engine start.
(2) Absolute load, fuel level (if used to enable or disable any
other monitors), barometric pressure (directly measured or estimated),
engine control module system voltage, and commanded equivalence ratio.
(3) Number of stored MIL-on DTCs, catalyst temperature (if directly
measured or estimated for purposes of enabling the catalyst
monitor(s)), monitor status (i.e., disabled for the rest of this drive
cycle, complete this drive cycle, or not complete this drive cycle)
since last engine shut-off for each monitor used for ready status,
distance traveled (or engine run time for engines not using vehicle
speed information) while MIL activated, distance traveled (or engine
run time for engines not using vehicle speed information) since DTC
memory last erased, and number of warm-up cycles since DTC memory last
erased, OBD requirements to which the engine is certified (e.g.,
California OBD, EPA OBD, European OBD, non-OBD) and MIL status (i.e.,
commanded-on or commanded-off).
(B) For diesel engines.
(1) Calculated load (engine torque as a percentage of maximum
torque available at the current engine speed), driver's demand engine
torque (as a percentage of maximum engine torque), actual engine torque
(as a percentage of maximum engine torque), reference engine maximum
torque, reference maximum engine torque as a function of engine speed
(suspect parameter numbers (SPN) 539 through 543 defined by SAE J1939
within parameter group number (PGN) 65251 for engine configuration),
engine coolant temperature, engine oil temperature (if used for
emission control or any OBD monitors), engine speed, and time elapsed
since engine start.
(2) Fuel level (if used to enable or disable any other monitors),
vehicle speed (if used for emission control or any OBD monitors),
barometric pressure (directly measured or estimated), and engine
control module system voltage.
(3) Number of stored MIL-on DTCs, monitor status (i.e., disabled
for the rest of this drive cycle, complete this drive cycle, or not
complete this drive cycle) since last engine shut-off for each monitor
used for ready status, distance traveled (or engine run time for
engines not using vehicle speed information) while MIL activated,
distance traveled (or engine run time for engines not using vehicle
speed information) since DTC memory last erased, number of warm-up
cycles since DTC memory last erased, OBD requirements to which the
engine is certified (e.g., California OBD, EPA OBD, European OBD, non-
OBD), and MIL status (i.e., commanded-on or commanded-off).
(4) NOX NTE control area status (i.e., inside control
area, outside control area, inside manufacturer-specific NOX
NTE carve-out area, or deficiency active area) and PM NTE control area
status (i.e., inside control area, outside control area, inside
manufacturer-specific PM NTE carve-out area, or deficiency active
area).
(5) For purposes of the calculated load and torque parameters in
paragraph (k)(4)(ii)(B)(1) of this section, manufacturers must report
the most accurate values that are calculated within the applicable
electronic control unit (e.g., the engine control module). Most
accurate, in this context, must be of sufficient accuracy, resolution,
and filtering to be used for the purposes of in-use emission testing
with the engine still in a vehicle (e.g., using portable emission
measurement equipment).
(C) For all engines so equipped.
(1) Absolute throttle position, relative throttle position, fuel
control system status (e.g., open loop, closed loop), fuel trim, fuel
pressure, ignition timing advance, fuel injection timing, intake air/
manifold temperature, engine intercooler temperature, manifold absolute
pressure, air flow rate from mass air flow sensor, secondary air status
(upstream, downstream, or atmosphere), ambient air temperature,
commanded purge valve duty cycle/position, commanded EGR valve duty
cycle/position, actual EGR valve duty cycle/position, EGR error between
actual and commanded, PTO status (active or not active), redundant
absolute throttle position (for electronic throttle or other systems
that utilize two or more sensors), absolute pedal position, redundant
absolute pedal position, commanded throttle motor position, fuel rate,
boost pressure, commanded/target boost pressure, turbo inlet air
temperature, fuel rail pressure, commanded fuel rail pressure, DPF
inlet pressure, DPF inlet temperature, DPF outlet pressure, DPF outlet
temperature, DPF delta pressure, exhaust pressure sensor output,
exhaust gas temperature sensor output, injection control pressure,
commanded injection control pressure, turbocharger/turbine speed,
variable geometry turbo position, commanded variable geometry turbo
position, turbocharger compressor inlet temperature, turbocharger
compressor inlet pressure, turbocharger turbine inlet temperature,
turbocharger turbine outlet temperature, waste gate valve position, and
glow plug lamp status.
(2) Oxygen sensor output, air/fuel ratio sensor output,
NOX sensor output, and evaporative system vapor pressure.
(iii) Freeze frame.
(A) ``Freeze frame'' information required to be stored pursuant to
paragraphs (b)(2)(iv), (h)(1)(iv)(D), and (h)(2)(vi) of this section
must be made available on demand through the data link connector.
(B) ``Freeze frame'' conditions must include the DTC that caused
the data to be stored along with all of the signals required in
paragraphs (k)(4)(ii)(A)(1) or (k)(4)(ii)(B)(1) of this section. Freeze
frame conditions must also include all of the signals required on the
engine in paragraphs (k)(4)(ii)(A)(2) and (k)(4)(ii)(B)(2) of this
section, and paragraph (k)(4)(ii)(C)(1) of this section that are used
for diagnostic or control purposes in the specific monitor or emission-
critical powertrain control unit that stored the DTC.
(C) Only one frame of data is required to be recorded. The
manufacturer may choose to store additional frames provided that at
least the required frame
[[Page 3314]]
can be read by, at a minimum, a manufacturer scan tool.
(iv) Diagnostic trouble codes.
(A) For all monitored components and systems, any stored pending,
MIL-on, and previous-MIL-on DTCs must be made available through the
diagnostic connector.
(B) The stored DTC must, to the extent possible, pinpoint the
probable cause of the malfunction or potential malfunction. To the
extent feasible, the manufacturer must use separate DTCs for every
monitor where the monitor and repair procedure or probable cause of the
malfunction is different. In general, rationality and functional checks
must use different DTCs than the respective circuit integrity checks.
Additionally, input component circuit integrity checks must use
different DTCs for distinct malfunctions (e.g., out-of-range low, out-
of-range high, open circuit).
(C) The manufacturer must use appropriate standard-defined DTCs
whenever possible. With Administrator approval, the manufacturer may
use manufacturer-defined DTCs in accordance with the applicable
standard's specifications. To do so, the manufacturer must be able to
show a lack of available standard-defined DTCs, uniqueness of the
monitor or monitored component, expected future usage of the monitor or
component, and estimated usefulness in providing additional diagnostic
and repair information to service technicians. Manufacturer-defined
DTCs must be used in a consistent manner (i.e., the same DTC shall not
be used to represent two different failure modes) across a
manufacturer's entire product line.
(D) A pending or MIL-on DTC (as required in paragraphs (g) through
(i) of this section) must be stored and available to, at a minimum, a
manufacturer scan tool within 10 seconds after a monitor has determined
that a malfunction or potential malfunction has occurred. A permanent
DTC must be stored and available to, at a minimum, a manufacturer scan
tool no later than the end of an ignition cycle in which the
corresponding MIL-on DTC that caused MIL activation has been stored.
(E) Pending DTCs for all components and systems (including those
monitored continuously and non-continuously) must be made available
through the diagnostic connector. A manufacturer using alternative
statistical protocols for MIL activation as allowed in paragraph
(b)(2)(iii) of this section must submit the details of their protocol
for setting pending DTCs. The protocol must be, overall, equivalent to
the requirements of this paragraph (k)(4)(iv)(E) and provide service
technicians with a quick and accurate indication of a potential
malfunction.
(F) Permanent DTC for all components and systems must be made
available through the diagnostic connector in a format that
distinguishes permanent DTCs from pending DTCs, MIL-on DTCs, and
previous-MIL-on DTCs. A MIL-on DTC must be stored as a permanent DTC no
later than the end of the ignition cycle and subsequently at all times
that the MIL-on DTC is commanding the MIL on. Permanent DTCs must be
stored in non-volatile random access memory (NVRAM) and shall not be
erasable by any scan tool command or by disconnecting power to the on-
board computer. Permanent DTCs must be erasable if the engine control
module is reprogrammed and the ready status described in paragraph
(k)(4)(i) of this section for all monitored components and systems are
set to ``not complete.'' The OBD system must have the ability to store
a minimum of four current MIL-on DTCs as permanent DTCs in NVRAM. If
the number of MIL-on DTCs currently commanding activation of the MIL
exceeds the maximum number of permanent DTCs that can be stored, the
OBD system must store the earliest detected MIL-on DTC as permanent
DTC. If additional MIL-on DTCs are stored when the maximum number of
permanent DTCs is already stored in NVRAM, the OBD system shall not
replace any existing permanent DTC with the additional MIL-on DTCs.
(v) Test results.
(A) Except as provided for in paragraph (k)(4)(v)(G) of this
section, for all monitored components and systems identified in
paragraphs (g) and (h) of this section, results of the most recent
monitoring of the components and systems and the test limits
established for monitoring the respective components and systems must
be stored and available through the data link.
(B) The test results must be reported such that properly
functioning components and systems (e.g., ``passing'' systems) do not
store test values outside of the established test limits. Test limits
must include both minimum and maximum acceptable values and must be
defined so that a test result equal to either test limit is a
``passing'' value, not a ``failing'' value.
(C) [Reserved.]
(D) The test results must be stored until updated by a more recent
valid test result or the DTC memory of the OBD system computer is
cleared. Upon DTC memory being cleared, test results reported for
monitors that have not yet completed with valid test results since the
last time the fault memory was cleared must report values of zero for
the test result and test limits.
(E) All test results and test limits must always be reported and
the test results must be stored until updated by a more recent valid
test result or the DTC memory of the OBD system computer is cleared.
(F) The OBD system must store and report unique test results for
each separate monitor.
(G) The requirements of this paragraph (k)(4)(v) do not apply to
continuous fuel system monitoring, cold start emission reduction
strategy monitoring, and continuous circuit monitoring.
(vi) Software calibration identification (CAL ID). On all engines,
a single software calibration identification number (CAL ID) for each
monitor or emission critical control unit(s) must be made available
through the data link connector. A unique CAL ID must be used for every
emission-related calibration and/or software set having at least one
bit of different data from any other emission-related calibration and/
or software set. Control units coded with multiple emission or
diagnostic calibrations and/or software sets must indicate a unique CAL
ID for each variant in a manner that enables an off-board device to
determine which variant is being used by the vehicle. Control units
that use a strategy that will result in MIL activation if the incorrect
variant is used (e.g., control units that contain variants for manual
and automatic transmissions but will activate the MIL if the selected
variant does not match the type of transmission mated to the engine)
are not required to use unique CAL IDs.
(vii) Software calibration verification number (CVN).
(A) All engines must use an algorithm to calculate a single
calibration verification number (CVN) that verifies the on-board
computer software integrity for each monitor or emission critical
control unit that is electronically reprogrammable. The CVN must be
made available through the data link connector. The CVN must indicate
whether the emission-related software and/or calibration data are valid
and applicable for the given vehicle and CAL ID.
(B) The CVN algorithm used to calculate the CVN must be of
sufficient complexity that the same CVN is difficult to achieve with
modified calibration values.
(C) The CVN must be calculated at least once per drive cycle and
stored until the CVN is subsequently updated. Except for immediately
after a
[[Page 3315]]
reprogramming event or a non-volatile memory clear or for the first 30
seconds of engine operation after a volatile memory clear or battery
disconnect, the stored value must be made available through the data
link connector to, at a minimum, a manufacturer scan tool. The stored
CVN value shall not be erased when DTC memory is erased or during
normal vehicle shut down (i.e., key-off/engine-off).
(D) [Reserved.]
(viii) Vehicle identification number (VIN).
(A) All vehicles must have the vehicle identification number (VIN)
available through the data link connector to, at a minimum, a
manufacturer scan tool. Only one electronic control unit per vehicle
may report the VIN to a scan tool.
(B) If the VIN is reprogrammable, all emission-related diagnostic
information identified in paragraph (k)(4)(ix)(A) of this section must
be erased in conjunction with reprogramming of the VIN.
(ix) Erasure of diagnostic information.
(A) For purposes of this paragraph (k)(4)(ix), ``emission-related
diagnostic information'' includes all of the following: ready status as
required by paragraph (k)(4)(i) of this section; data stream
information as required by paragraph (k)(4)(ii) of this section
including the number of stored MIL-on DTCs, distance traveled while MIL
activated, number of warm-up cycles since DTC memory last erased, and
distance traveled since DTC memory last erased; freeze frame
information as required by paragraph (k)(4)(iii) of this section;
pending, MIL-on, and previous-MIL-on DTCs as required by paragraph
(k)(4)(iv) of this section; and, test results as required by paragraph
(k)(4)(v) of this section.
(B) For all engines, the emission-related diagnostic information
must be erased if commanded by any scan tool and may be erased if the
power to the on-board computer is disconnected. If any of the emission-
related diagnostic information is commanded to be erased by any scan
tool, all emission-related diagnostic information must be erased from
all diagnostic or emission critical control units. The OBD system shall
not allow a scan tool to erase a subset of the emission-related
diagnostic information (e.g., the OBD system shall not allow a scan
tool to erase only one of three stored DTCs or only information from
one control unit without erasing information from the other control
unit(s)).
(5) In-use performance ratio tracking requirements.
(i) For each monitor required in paragraphs (g) through (i) of this
section to separately report an in-use performance ratio, manufacturers
must implement software algorithms to report a numerator and
denominator.
(ii) For the numerator, denominator, general denominator, and
ignition cycle counters required by paragraph (e) of this section, the
following numerical value specifications apply:
(A) Each number shall have a minimum value of zero and a maximum
value of 65,535 with a resolution of one.
(B) Each number shall be reset to zero only when a non-volatile
random access memory (NVRAM) reset occurs (e.g., reprogramming event)
or, if the numbers are stored in keep-alive memory (KAM), when KAM is
lost due to an interruption in electrical power to the control unit
(e.g., battery disconnect). Numbers shall not be reset to zero under
any other circumstances including when a scan tool command to clear
DTCs or reset KAM is received.
(C) To avoid overflow problems, if either the numerator or
denominator for a specific component reaches the maximum value of
65,535 2, both numbers shall be divided by two before
either is incremented again.
(D) To avoid overflow problems, if the ignition cycle counter
reaches the maximum value of 65,535 2, the ignition cycle
counter shall roll over and increment to zero on the next ignition
cycle.
(E) To avoid overflow problems, if the general denominator reaches
the maximum value of 65,535 2, the general denominator
shall roll over and increment to zero on the next drive cycle that
meets the general denominator definition.
(F) If a vehicle is not equipped with a component (e.g., oxygen
sensor bank 2, secondary air system), the corresponding numerator and
denominator for that specific component shall always be reported as
zero.
(iii) For the ratio required by paragraph (e) of this section, the
following numerical value specifications apply:
(A) The ratio shall have a minimum value of zero and a maximum
value of 7.99527 with a resolution of 0.000122.
(B) The ratio for a specific component shall be considered to be
zero whenever the corresponding numerator is equal to zero and the
corresponding denominator is not zero.
(C) The ratio for a specific component shall be considered to be
the maximum value of 7.99527 if the corresponding denominator is zero
or if the actual value of the numerator divided by the denominator
exceeds the maximum value of 7.99527.
(6) Engine run time tracking requirements.
(i) For all gasoline and diesel engines, the manufacturer must
implement software algorithms to track and report individually the
amount of time the engine has been operated in the following
conditions:
(A) Total engine run time.
(B) Total idle run time (with ``idle'' defined as accelerator pedal
released by the driver, vehicle speed less than or equal to one mile
per hour, engine speed greater than or equal to 50 to 150 rpm below the
normal, warmed-up idle speed (as determined in the drive position for
vehicles equipped with an automatic transmission), and power take-off
not active).
(C) Total run time with power take off active.
(ii) For each counter specified in paragraph (k)(6)(i) of this
section, the following numerical value specifications apply:
(A) Each number shall be a four-byte value with a minimum value of
zero, a resolution of one second per bit, and an accuracy of ten seconds per drive cycle.
(B) Each number shall be reset to zero only when a non-volatile
memory reset occurs (e.g., reprogramming event). Numbers shall not be
reset to zero under any other circumstances including when a scan tool
(generic or enhanced) command to clear fault codes or reset KAM is
received.
(C) To avoid overflow problems, if any of the individual counters
reach the maximum value, all counters shall be divided by two before
any are incremented again.
(D) The counters shall be made available to, at a minimum, a
manufacturer scan tool and may be rescaled when transmitted from a
resolution of one second per bit to no more than three minutes per bit.
(l) Monitoring system demonstration requirements for certification.
(1) General.
(i) The manufacturer must submit emissions test data from one or
more durability demonstration test engines (test engines).
(ii) The Administrator may approve other demonstration protocols if
the manufacturer can provide comparable assurance that the malfunction
criteria are chosen based on meeting the malfunction criteria
requirements and that the timeliness of malfunction detection is within
the constraints of the applicable monitoring requirements.
(iii) For flexible fuel engines capable of operating on more than
one fuel or
[[Page 3316]]
fuel combinations, the manufacturer must submit a plan for providing
emission test data. The plan must demonstrate that testing will
represent properly the expected in-use fuel or fuel combinations.
(2) Selection of test engines.
(i) Prior to submitting any applications for certification for a
model year, the manufacturer must notify the Administrator regarding
the planned engine families and engine ratings within each family for
that model year. The Administrator will select the engine family(ies)
and the specific engine rating within the engine family(ies) that the
manufacturer shall use as demonstration test engines. The selection of
test vehicles for production evaluation testing as specified in
paragraph (j)(2) of this section may take place during this selection
process.
(ii) The manufacturer must provide emissions test data from the OBD
parent rating as defined in paragraph (o)(1) of this section.
(iii) For the test engine, the manufacturer must use an engine aged
for a minimum of 125 hours fitted with exhaust aftertreatment emission
controls aged to be representative of useful life aging. The
manufacturer is required to submit a description of the accelerated
aging process and/or supporting data. The process and/or data must
demonstrate assurance that deterioration of the exhaust aftertreatment
emission controls is stabilized sufficiently such that it represents
emission control performance at the end of the useful life.
(3) Required testing. Except as otherwise described in this
paragraph (l)(3), the manufacturer must perform single malfunction
testing based on the applicable test with the components/systems set at
their malfunction criteria limits as determined by the manufacturer for
meeting the emissions thresholds required in paragraphs (g), (h), and
(i) of this section.
(i) Required testing for diesel-fueled/compression ignition
engines.
(A) Fuel system. The manufacturer must perform a separate test for
each malfunction limit established by the manufacturer for the fuel
system parameters (e.g., fuel pressure, injection timing) specified in
paragraphs (g)(1)(ii)(A) through (g)(1)(ii)(C) of this section. When
performing a test for a specific parameter, the fuel system must be
operating at the malfunction criteria limit for the applicable
parameter only. All other parameters must be operating with normal
characteristics. In conducting the fuel system demonstration tests, the
manufacturer may use computer modifications to cause the fuel system to
operate at the malfunction limit if the manufacturer can demonstrate
that the computer modifications produce test results equivalent to an
induced hardware malfunction.
(B) [Reserved.]
(C) EGR system. The manufacturer must perform a separate test for
each malfunction limit established by the manufacturer for the EGR
system parameters (e.g., low flow, high flow, slow response) specified
in paragraphs (g)(3)(ii)(A) through (g)(3)(ii)(C) of this section and
in (g)(3)(ii)(E) of this section. In conducting the EGR system slow
response demonstration tests, the manufacturer may use computer
modifications to cause the EGR system to operate at the malfunction
limit if the manufacturer can demonstrate that the computer
modifications produce test results equivalent to an induced hardware
malfunction.
(D) Turbo boost control system. The manufacturer must perform a
separate test for each malfunction limit established by the
manufacturer for the turbo boost control system parameters (e.g.,
underboost, overboost, response) specified in paragraphs (g)(4)(ii)(A)
through (g)(4)(ii)(C) of this section and in (g)(4)(ii)(E) of this
section.
(E) NMHC catalyst. The manufacturer must perform a separate test
for each monitored NMHC catalyst(s). The catalyst(s) being evaluated
must be deteriorated to the applicable malfunction limit established by
the manufacturer for the monitoring required by paragraph (g)(5)(ii)(A)
of this section and using methods established by the manufacturer in
accordance with paragraph (l)(7) of this section. For each monitored
NMHC catalyst(s), the manufacturer must also demonstrate that the OBD
system will detect a catalyst malfunction with the catalyst at its
maximum level of deterioration (i.e., the substrate(s) completely
removed from the catalyst container or ``empty'' can). Emissions data
are not required for the empty can demonstration.
(F) NOX catalyst. The manufacturer must perform a
separate test for each monitored NOX catalyst(s) (e.g., SCR
catalyst). The catalyst(s) being evaluated must be deteriorated to the
applicable malfunction criteria established by the manufacturer for the
monitoring required by paragraphs (g)(6)(ii)(A) and (g)(6)(ii)(B) of
this section and using methods established by the manufacturer in
accordance with paragraph (l)(7) of this section. For each monitored
NOX catalyst(s), the manufacturer must also demonstrate that
the OBD system will detect a catalyst malfunction with the catalyst at
its maximum level of deterioration (i.e., the substrate(s) completely
removed from the catalyst container or ``empty'' can). Emissions data
are not required for the empty can demonstration.
(G) NOX adsorber. The manufacturer must perform a test
using a NOX adsorber(s) deteriorated to the applicable
malfunction limit established by the manufacturer for the monitoring
required by paragraph (g)(7)(ii)(A) of this section. The manufacturer
must also demonstrate that the OBD system will detect a NOX
adsorber malfunction with the NOX adsorber at its maximum
level of deterioration (i.e., the substrate(s) completely removed from
the container or ``empty'' can). Emissions data are not required for
the empty can demonstration.
(H) Diesel particulate filter. The manufacturer must perform a
separate test using a DPF deteriorated to the applicable malfunction
limits established by the manufacturer for the monitoring required by
paragraphs (g)(8)(ii)(A), (g)(8)(ii)(B), and (g)(8)(ii)(D) of this
section. The manufacturer must also demonstrate that the OBD system
will detect a DPF malfunction with the DPF at its maximum level of
deterioration (i.e., the filter(s) completely removed from the filter
container or ``empty'' can). Emissions data are not required for the
empty can demonstration.
(I) Exhaust gas sensor. The manufacturer must perform a separate
test for each malfunction limit established by the manufacturer for the
monitoring required in paragraphs (g)(9)(ii)(A), (g)(9)(iii)(A), and
(g)(9)(iv)(A) of this section. When performing a test, all exhaust gas
sensors used for the same purpose (e.g., for the same feedback control
loop, for the same control feature on parallel exhaust banks) must be
operating at the malfunction criteria limit for the applicable
parameter only. All other exhaust gas sensor parameters must be
operating with normal characteristics.
(J) VVT system. The manufacturer must perform a separate test for
each malfunction limit established by the manufacturer for the
monitoring required in paragraphs (g)(10)(ii)(A) and (g)(10)(ii)(B) of
this section. In conducting the VVT system demonstration tests, the
manufacturer may use computer modifications to cause the VVT system to
operate at the malfunction limit if the manufacturer can demonstrate
that the computer modifications produce test results equivalent to an
induced hardware malfunction.
[[Page 3317]]
(K) For each of the testing requirements of this paragraph
(l)(3)(i), if the manufacturer has established that only a functional
check is required because no failure or deterioration of the specific
tested system could result in an engine's emissions exceeding the
applicable emissions thresholds, the manufacturer is not required to
perform a demonstration test; however, the manufacturer is required to
provide the data and/or engineering analysis used to determine that
only a functional test of the system(s) is required.
(ii) Required testing for gasoline-fueled/spark-ignition engines.
(A) Fuel system. For engines with adaptive feedback based on the
primary fuel control sensor(s), the manufacturer must perform a test
with the adaptive feedback based on the primary fuel control sensor(s)
at the rich limit(s) and a test at the lean limit(s) established by the
manufacturer as required by paragraph (h)(1)(ii)(A) of this section to
detect a malfunction before emissions exceed applicable emissions
thresholds. For engines with feedback based on a secondary fuel control
sensor(s) and subject to the malfunction criteria in paragraph
(h)(1)(ii)(A) of this section, the manufacturer must perform a test
with the feedback based on the secondary fuel control sensor(s) at the
rich limit(s) and a test at the lean limit(s) established by the
manufacturer as required by paragraph (h)(1)(ii)(A) of this section to
detect a malfunction before emissions exceed the applicable emissions
thresholds. For other fuel metering or control systems, the
manufacturer must perform a test at the criteria limit(s). For purposes
of fuel system testing as required by this paragraph (l)(3)(ii)(A), the
malfunction(s) induced may result in a uniform distribution of fuel and
air among the cylinders. Non uniform distribution of fuel and air used
to induce a malfunction shall not cause misfire. In conducting the fuel
system demonstration tests, the manufacturer may use computer
modifications to cause the fuel system to operate at the malfunction
limit. To do so, the manufacturer must be able to demonstrate that the
computer modifications produce test results equivalent to an induced
hardware malfunction.
(B) Misfire. The manufacturer must perform a test at the
malfunction criteria limit specified in paragraph (h)(2)(ii)(B) of this
section.
(C) EGR system. The manufacturer must perform a test at each flow
limit calibrated to the malfunction criteria specified in paragraphs
(h)(3)(ii)(A) and (h)(3)(ii)(B) of this section.
(D) Cold start emission reduction strategy. The manufacturer must
perform a test at the malfunction criteria for each component monitored
according to paragraph (h)(4)(ii)(A) of this section.
(E) Secondary air system. The manufacturer must perform a test at
each flow limit calibrated to the malfunction criteria specified in
paragraphs (h)(5)(ii)(A) and (h)(5)(ii)(B) of this section.
(F) Catalyst. The manufacturer must perform a test using a catalyst
system deteriorated to the malfunction criteria specified in paragraph
(h)(6)(ii) of this section using methods established by the
manufacturer in accordance with paragraph (l)(7)(ii) of this section.
The manufacturer must also demonstrate that the OBD system will detect
a catalyst system malfunction with the catalyst system at its maximum
level of deterioration (i.e., the substrate(s) completely removed from
the catalyst container or ``empty'' can). Emission data are not
required for the empty can demonstration.
(G) Exhaust gas sensor. The manufacturer must perform a test with
all primary exhaust gas sensors used for fuel control simultaneously
possessing a response rate deteriorated to the malfunction criteria
limit specified in paragraph (h)(8)(ii)(A) of this section. The
manufacturer must also perform a test for any other primary or
secondary exhaust gas sensor parameter under parargraphs (h)(8)(ii)(A)
and (h)(8)(iii)(A) of this section that can cause engine emissions to
exceed the applicable emissions thresholds (e.g., shift in air/fuel
ratio at which oxygen sensor switches, decreased amplitude). When
performing additional test(s), all primary and secondary (if
applicable) exhaust gas sensors used for emission control must be
operating at the malfunction criteria limit for the applicable
parameter only. All other primary and secondary exhaust gas sensor
parameters must be operating with normal characteristics.
(H) VVT system. The manufacturer must perform a test at each target
error limit and slow response limit calibrated to the malfunction
criteria specified in (h)(9)(ii)(A) and (h)(9)(ii)(B) of this section.
In conducting the VVT system demonstration tests, the manufacturer may
use computer modifications to cause the VVT system to operate at the
malfunction limit. To do so, the manufacturer must be able to
demonstrate that the computer modifications produce test results
equivalent to an induced hardware malfunction.
(I) For each of the testing requirements of this paragraph
(l)(3)(ii), if the manufacturer has established that only a functional
check is required because no failure or deterioration of the specific
tested system could cause an engine's emissions to exceed the
applicable emissions thresholds, the manufacturer is not required to
perform a demonstration test; however the manufacturer is required to
provide the data and/or engineering analyses used to determine that
only a functional test of the system(s) is required.
(iii) Required testing for all engines.
(A) Other emission control systems. The manufacturer must conduct
demonstration tests for all other emission control components (e.g.,
hydrocarbon traps, adsorbers) designed and calibrated to a malfunction
limit based on an emissions threshold based on the requirements of
paragraph (i)(4) of this section.
(B) For each of the testing requirements of paragraph
(l)(3)(iii)(A) of this section, if the manufacturer has established
that only a functional check is required because no failure or
deterioration of the specific tested system could result in an engine's
emissions exceeding the applicable emissions thresholds, the
manufacturer is not required to perform a demonstration test; however,
the manufacturer is required to provide the data and/or engineering
analysis used to determine that only a functional test of the system(s)
is required.
(iv) The manufacturer may electronically simulate deteriorated
components but shall not make any engine control unit modifications
when performing demonstration tests unless approved by the
Administrator. All equipment necessary to duplicate the demonstration
test must be made available to the Administrator upon request.
(4) Testing protocol.
(i) Preconditioning. The manufacturer must use an applicable cycle
for preconditioning test engines prior to conducting each of the
emission tests required by paragraph (l)(3) of this section. The
manufacturer may perform a single additional preconditioning cycle,
identical to the initial one, after a 20 minute hot soak but must
demonstrate that such an additional cycle is necessary to stabilize the
emissions control system. A practice of requiring a cold soak prior to
conducting preconditioning cycles is not permitted.
(ii) Test sequence.
(A) The manufacturer must set individually each system or component
on the test engine at the malfunction
[[Page 3318]]
criteria limit prior to conducting the applicable preconditioning
cycle(s). If a second preconditioning cycle is permitted in accordance
with paragraph (l)(4)(i) of this section, the manufacturer may adjust
the system or component to be tested before conducting the second
preconditioning cycle. The manufacturer shall not replace, modify, or
adjust the system or component after the last preconditioning cycle has
been completed.
(B) After preconditioning, the test engine must be operated over
the applicable cycle to allow for the initial detection of the tested
system or component malfunction. This test cycle may be omitted from
the testing protocol if it is unnecessary. If required by the
monitoring strategy being tested, a cold soak may be performed prior to
conducting this test cycle.
(C) The test engine must then be operated over the applicable
exhaust emissions test.
(iii) [Reserved.]
(iv) The manufacturer may request approval to use an alternative
testing protocol for demonstration of MIL activation if the engine
dynamometer emission test cycle does not allow all of a given monitor's
enable conditions to be satisfied. The manufacturer may request the use
of an alternative engine dynamometer test cycle or the use of chassis
testing to demonstrate proper MIL activation. To do so, the
manufacturer must demonstrate the technical necessity for using an
alternative test cycle and the degree to which the alternative test
cycle demonstrates that in-use operation with the malfunctioning
component will result in proper MIL activation.
(5) Evaluation protocol. Full OBD engine ratings, as defined by
paragraph (o)(1) of this section, shall be evaluated according to the
following protocol:
(i) For all tests conducted as required by paragraph (l) of this
section, the MIL must activate before the end of the first engine start
portion of the applicable test.
(ii) If the MIL activates prior to emissions exceeding the
applicable malfunction criteria limits specified in paragraphs (g)
through (i) of this section, no further demonstration is required. With
respect to the misfire monitor demonstration test, if the manufacturer
has elected to use the minimum misfire malfunction criteria of one
percent as allowed in paragraph (h)(2)(ii)(B) of this section, no
further demonstration is required provided the MIL activates with
engine misfire occurring at the malfunction criteria limit.
(iii) If the MIL does not activate when the system or component is
set at its malfunction criteria limit(s), the criteria limit(s) or the
OBD system is not acceptable.
(A) Except for testing of the catalyst or DPF system, if the MIL
first activates after emissions exceed the applicable malfunction
criteria specified in paragraphs (g) through (i) of this section, the
test engine shall be retested with the tested system or component
adjusted so that the MIL will activate before emissions exceed the
applicable malfunction criteria specified in paragraphs (g) through (i)
of this section. If the component cannot be so adjusted because an
alternative fuel or emission control strategy is used when a
malfunction is detected (e.g., open loop fuel control used after an
oxygen sensor malfunction is detected), the test engine shall be
retested with the component adjusted to the worst acceptable limit
(i.e., the applicable OBD monitor indicates that the component is
performing at or slightly better than the malfunction criteria limit).
When tested with the component so adjusted, the MIL must not activate
during the test and the engine emissions must be below the applicable
malfunction criteria specified in paragraphs (g) through (i) of this
section.
(B) In testing the catalyst or DPF system, if the MIL first
activates after emissions exceed the applicable emissions threshold(s)
specified in paragraphs (g) and (h) of this section, the tested engine
shall be retested with a less deteriorated catalyst or DPF system
(i.e., more of the applicable engine out pollutants are converted or
trapped). For the OBD system to be approved, testing shall be continued
until the MIL activates with emissions below the applicable thresholds
of paragraphs (g) and (h) of this section, or the MIL activates with
emissions within a range no more than 20 percent below the applicable
emissions thresholds and 10 percent or less above those emissions
thresholds.
(iv) If an OBD system is determined to be unacceptable by the
criteria of this paragraph (l)(5) of this section, the manufacturer may
recalibrate and retest the system on the same test engine. In such a
case, the manufacturer must confirm, by retesting, that all systems and
components that were tested prior to the recalibration and are affected
by it still function properly with the recalibrated OBD system.
(6) Confirmatory testing.
(i) The Administrator may perform confirmatory testing to verify
the emission test data submitted by the manufacturer as required by
this paragraph (l) of this section comply with its requirements and the
malfunction criteria set forth in paragraphs (g) through (i) of this
section. Such confirmatory testing is limited to the test engine
required by paragraph (l)(2) of this section.
(ii) To conduct this confirmatory testing, the Administrator may
install appropriately deteriorated or malfunctioning components (or
simulate them) in an otherwise properly functioning test engine of an
engine rating represented by the demonstration test engine in order to
test any of the components or systems required to be tested by
paragraph (l) of this section. The manufacturer shall make available,
if requested, an engine and all test equipment (e.g., malfunction
simulators, deteriorated components) necessary to duplicate the
manufacturer's testing. Such a request from the Administrator shall
occur within six months of reviewing and approving the demonstration
test engine data submitted by the manufacturer for the specific engine
rating.
(7) Catalyst aging.
(i) Diesel catalysts. For purposes of determining the catalyst
malfunction limits for the monitoring required by paragraphs
(g)(5)(ii)(A), (g)(5)(ii)(B), and (g)(6)(ii)(A) of this section, where
those catalysts are monitored individually, the manufacturer must use a
catalyst deteriorated to the malfunction criteria using methods
established by the manufacturer to represent real world catalyst
deterioration under normal and malfunctioning engine operating
conditions. For purposes of determining the catalyst malfunction limits
for the monitoring required by paragraphs (g)(5)(ii)(A), (g)(5)(ii)(B),
and (g)(6)(ii)(A) of this section, where those catalysts are monitored
in combination with other catalysts, the manufacturer must submit their
catalyst system aging and monitoring plan to the Administrator as part
of their certification documentation package. The plan must include the
description, emission control purpose, and location of each component,
the monitoring strategy for each component and/or combination of
components, and the method for determining the applicable malfunction
criteria including the deterioration/aging process.
(ii) Gasoline catalysts. For the purposes of determining the
catalyst system malfunction criteria in paragraph (h)(6)(ii) of this
section, the manufacturer must use a catalyst system deteriorated to
the malfunction criteria using methods established by the manufacturer
to represent real world catalyst deterioration under normal and
malfunctioning operating conditions. The malfunction criteria must be
[[Page 3319]]
established by using a catalyst system with all monitored and
unmonitored (downstream of the sensor utilized for catalyst monitoring)
catalysts simultaneously deteriorated to the malfunction criteria
except for those engines that use fuel shutoff to prevent over-fueling
during engine misfire conditions. For such engines, the malfunction
criteria must be established by using a catalyst system with all
monitored catalysts simultaneously deteriorated to the malfunction
criteria while unmonitored catalysts shall be deteriorated to the end
of the engine's useful life.
(m) Certification documentation requirements.
(1) When submitting an application for certification of an engine,
the manufacturer must submit the following documentation. If any of the
items listed here are standardized for all of the manufacturer's
engines, the manufacturer may, for each model year, submit one set of
documents covering the standardized items for all of its engines.
(i) For the required documentation that is not standardized across
all engines, the manufacturer may be allowed to submit documentation
for certification from one engine that is representative of other
engines. All such engines shall be considered to be part of an OBD
certification documentation group. To represent the OBD group, the
chosen engine must be certified to the most stringent emissions
standards and OBD monitoring requirements and cover all of the
emissions control devices for the engines in the group and covered by
the submitted documentation. Such OBD groups must be approved in
advance of certification.
(ii) Upon approval, one or more of the documentation requirements
of this paragraph (m) of this section may be waived or modified if the
information required is redundant or unnecessarily burdensome to
generate.
(iii) To the extent possible, the certification documentation must
use SAE J1930 or J2403 terms, abbreviations, and acronyms.
(2) Unless otherwise specified, the following information must be
submitted as part of the certification application and prior to
receiving a certificate.
(i) A description of the functional operation of the OBD system
including a complete written description for each monitoring strategy
that outlines every step in the decision-making process of the monitor.
Algorithms, diagrams, samples of data, and/or other graphical
representations of the monitoring strategy shall be included where
necessary to adequately describe the information.
(ii) A table including the following information for each monitored
component or system (either computer-sensed or computer-controlled) of
the emissions control system:
(A) Corresponding diagnostic trouble code.
(B) Monitoring method or procedure for malfunction detection.
(C) Primary malfunction detection parameter and its type of output
signal.
(D) Malfunction criteria limits used to evaluate output signal of
primary parameter.
(E) Other monitored secondary parameters and conditions (in
engineering units) necessary for malfunction detection.
(F) Monitoring time length and frequency of monitoring events.
(G) Criteria for storing a diagnostic trouble code.
(H) Criteria for activating a malfunction indicator light.
(I) Criteria used for determining out-of-range values and input
component rationality checks.
(iii) Whenever possible, the table required by paragraph (m)(2)(ii)
of this section shall use the following engineering units:
(A) Degrees Celsius for all temperature criteria.
(B) KiloPascals (KPa) for all pressure criteria related to manifold
or atmospheric pressure.
(C) Grams (g) for all intake air mass criteria.
(D) Pascals (Pa) for all pressure criteria related to evaporative
system vapor pressure.
(E) Miles per hour (mph) for all vehicle speed criteria.
(F) Relative percent (%) for all relative throttle position
criteria (as defined in SAE J1979/J1939).
(G) Voltage (V) for all absolute throttle position criteria (as
defined in SAE J1979/J1939).
(H) Per crankshaft revolution (/rev) for all changes per ignition
event based criteria (e.g., g/rev instead of g/stroke or g/firing).
(I) Per second (/sec) for all changes per time based criteria
(e.g., g/sec).
(J) Percent of nominal tank volume (%) for all fuel tank level
criteria.
(iv) A logic flowchart describing the step-by-step evaluation of
the enable criteria and malfunction criteria for each monitored
emission related component or system.
(v) Emissions test data, a description of the testing sequence
(e.g., the number and types of preconditioning cycles), approximate
time (in seconds) of MIL activation during the test, diagnostic trouble
code(s) and freeze frame information stored at the time of detection,
corresponding test results (e.g. SAE J1979 Mode/Service $06, SAE J1939
Diagnostic Message 8 (DM8)) stored during the test, and a description
of the modified or deteriorated components used for malfunction
simulation with respect to the demonstration tests specified in
paragraph (l) of this section. The freeze frame data are not required
for engines subject to paragraph (o)(2) of this section.
(vi) For gasoline engines, data supporting the misfire monitor,
including:
(A) The established percentage of misfire that can be tolerated
without damaging the catalyst over the full range of engine speed and
load conditions.
(B) Data demonstrating the probability of detection of misfire
events by the misfire monitoring system over the full engine speed and
load operating range for the following misfire patterns: random
cylinders misfiring at the malfunction criteria established in
paragraph (h)(2)(ii)(B) of this section, one cylinder continuously
misfiring, and paired cylinders continuously misfiring.
(C) Data identifying all disablement of misfire monitoring that
occurs during the FTP. For every disablement that occurs during the
cycles, the data shall identify: when the disablement occurred relative
to the driver's trace, the number of engine revolutions during which
each disablement was present, and which disable condition documented in
the certification application caused the disablement.
(D) Manufacturers are not required to use the durability
demonstration engine to collect the misfire data required by paragraph
(m)(2)(vi) of this section.
(vii) Data supporting the limit for the time between engine
starting and attaining the designated heating temperature for after-
start heated catalyst systems.
(viii) Data supporting the criteria used to detect a malfunction of
the fuel system, EGR system, boost pressure control system, catalyst,
NOX adsorber, DPF, cold start emission reduction strategy,
secondary air, evaporative system, VVT system, exhaust gas sensors, and
other emission controls that causes emissions to exceed the applicable
malfunction criteria specified in paragraphs (g) through (i) of this
section. For diesel engine monitors required by paragraphs (g) and (i)
of this section that are required to indicate a malfunction before
emissions exceed an emission threshold based on any applicable standard
(e.g., 2.5 times any
[[Page 3320]]
of the applicable standards), the test cycle and standard determined by
the manufacturer to be the most stringent for each applicable monitor
in accordance with paragraph (f)(1) of this section.
(ix) A list of all electronic powertrain input and output signals
(including those not monitored by the OBD system) that identifies which
signals are monitored by the OBD system. For input and output signals
that are monitored as comprehensive components, the listing shall also
identify the specific diagnostic trouble code for each malfunction
criteria (e.g., out-of-range low, out-of-range high, open circuit,
rationality low, rationality high).
(x) A written description of all parameters and conditions
necessary to begin closed-loop/feedback control of emission control
systems (e.g., fuel system, boost pressure, EGR flow, SCR reductant
delivery, DPF regeneration, fuel system pressure).
(xi) A written identification of the communication protocol
utilized by each engine for communication with a scan tool.
(xii) Reserved.
(xiii) A written description of the method used by the manufacturer
to meet the requirements of paragraph (i)(2) of this section (crankcase
ventilation system monitoring) including diagrams or pictures of valve
and/or hose connections.
(xiv) Build specifications provided to engine purchasers or chassis
manufacturers detailing all specifications or limitations imposed on
the engine purchaser relevant to OBD requirements or emissions
compliance (e.g., cooling system heat rejection rates). A description
of the method or copies of agreements used to ensure engine purchasers
or chassis manufacturers will comply with the OBD and emissions
relevant build specifications (e.g., signed agreements, required audit/
evaluation procedures).
(xv) Any other information determined by the Administrator to be
necessary to demonstrate compliance with the requirements of this
section.
(n) Deficiencies.
(1) Upon application by the manufacturer, the Administrator may
accept an OBD system as compliant even though specific requirements are
not fully met. Such compliances without meeting specific requirements,
or deficiencies, will be granted only if compliance is infeasible or
unreasonable considering such factors as, but not limited to: technical
feasibility of the given monitor and lead time and production cycles
including phase-in or phase-out of engines or vehicle designs and
programmed upgrades of computers. Unmet requirements shall not be
carried over from the previous model year except where unreasonable
hardware or software modifications are necessary to correct the
deficiency, and the manufacturer has demonstrated an acceptable level
of effort toward compliance as determined by the Administrator.
Furthermore, EPA will not accept any deficiency requests that include
the complete lack of a major diagnostic monitor (``major'' diagnostic
monitors being those for exhaust aftertreatment devices, oxygen sensor,
air-fuel ratio sensor, NOX sensor, engine misfire,
evaporative leaks, and diesel EGR, if equipped), with the possible
exception of the special provisions for alternative fueled engines. For
alternative fueled heavy-duty engines (e.g. natural gas, liquefied
petroleum gas, methanol, ethanol), manufacturers may request the
Administrator to waive specific monitoring requirements of this section
for which monitoring may not be reliable with respect to the use of the
alternative fuel. At a minimum, alternative fuel engines must be
equipped with an OBD system meeting OBD requirements to the extent
feasible as approved by the Administrator.
(2) In the event the manufacturer seeks to carry-over a deficiency
from a past model year to the current model year, the manufacturer must
re-apply for approval to do so. In considering the request to carry-
over a deficiency, the Administrator shall consider the manufacturer's
progress towards correcting the deficiency. The Administrator may not
allow manufacturers to carry over monitoring system deficiencies for
more than two model years unless it can be demonstrated that
substantial engine hardware modifications and additional lead time
beyond two years are necessary to correct the deficiency.
(3) A deficiency shall not be granted retroactively (i.e., after
the engine has been certified).
(o) Implementation schedule. Except as provided for in paragraphs
(o)(4) and (o)(5) of this section, the requirements of this section
must be met according to the following provisions:
(1) Full OBD. The manufacturer must implement an OBD system meeting
the requirements of this section on one engine rating within one engine
family of the manufacturer's product line. This ``full OBD'' rating
will be known as the ``OBD parent'' rating. The OBD parent rating must
be chosen as the rating having the highest weighted projected U.S.
sales within the engine family having the highest weighted projected
U.S. sales, with U.S. sales being weighted by the useful life of the
engine rating.
(2) Extrapolated OBD. For all other engine ratings within the
engine family from which the OBD parent rating has been selected, the
manufacturer must implement an OBD system meeting the requirements of
this section except that the OBD system is not required to detect a
malfunction prior to exceeding the emission thresholds shown in Table 1
of paragraph (g) of this section and Table 2 of paragraph (h) of this
section. These extrapolated OBD engines will be known as the ``OBD
child'' ratings. On these OBD child ratings, rather than detecting a
malfunction prior to exceeding the emission thresholds, the
manufacturer must submit a plan for Administrator review and approval
that details the engineering evaluation the manufacturer will use to
establish the malfunction criteria for the OBD child ratings. The plan
must demonstrate both the use of good engineering judgment in
establishing the malfunction criteria, and robust detection of
malfunctions, including consideration of differences of base engine,
calibration, emission control components, and emission control
strategies.
(3) Engine families other than those from which the parent and
child ratings have been selected are not subject to the requirements of
this section.
(4) Small volume manufacturers, as defined in Sec. 86.094-14(b)(1)
and (2), are exempt from the requirements of Sec. 86.010-18.
(5) Engines certified as alternative fueled engines are exempt from
the requirements of Sec. 86.010-18.
(p) In-use compliance standards. For monitors required to indicate
a malfunction before emissions exceed a certain emission threshold
(e.g., 2.5 times any of the applicable standards):
(1) On the full OBD rating (i.e., the parent rating) as defined in
paragraph (o)(1) of this section, separate in-use emissions thresholds
shall apply. These thresholds are determined by doubling the applicable
thresholds as shown in Table 1 of paragraph (g) and Table 2 of
paragraph (h) of this section. The resultant thresholds apply only in-
use and do not apply for certification or selective enforcement
auditing.
(2) The extrapolated OBD ratings (i.e., the child ratings) as
defined in paragraph (o)(2) of this section shall not be evaluated
against emissions levels for purposes of OBD compliance in-use.
(3) Only the test cycle and standard determined and identified by
the manufacturer at the time of certification in accordance with
paragraph (f) of this section as the most stringent shall be
[[Page 3321]]
used for the purpose of determining OBD system noncompliance in-use.
(4) An OBD system shall not be considered noncompliant solely due
to a failure or deterioration mode of a monitored component or system
that could not have been reasonably foreseen to occur by the
manufacturer.
8. Section 86.010-30 is added to Subpart A to read as follows:
Sec. 86.010-30 Certification.
Section 86.010-30 includes text that specifies requirements that
differ from Sec. Sec. 86.094-30, 86.095-30, 86.096-30, 86.098-30,
86.001-30, 86.004-30 or 86.007-30. Where a paragraph in Sec. 86.094-
30, Sec. 86.095-30, Sec. 86.096-30, Sec. 86.098-30, Sec. 86.001-30,
Sec. 86.004-30 or Sec. 86.007-30 is identical and applicable to Sec.
86.010-30, this may be indicated by specifying the corresponding
paragraph and the statement ``[Reserved]. For guidance see Sec.
86.094-30.'' or ``[Reserved]. For guidance see Sec. 86.095-30.'' or
``[Reserved]. For guidance see Sec. 86.096-30.'' or ``[Reserved]. For
guidance see Sec. 86.098-30.'' or ``[Reserved]. For guidance see Sec.
86.001-30.'' or ``[Reserved]. For guidance see Sec. 86.004-30.'' or
``[Reserved]. For guidance see Sec. 86.007-30.''
(a)(1) and (a)(2) [Reserved]. For guidance see Sec. 86.094-30.
(a)(3)(i) through (a)(4)(ii) [Reserved]. For guidance see Sec.
86.004-30.
(a)(4)(iii) introductory text through (a)(4)(iii)(C) [Reserved].
For guidance see Sec. 86.094-30.
(a)(4)(iv) introductory text [Reserved]. For guidance see Sec.
86.095-30.
(a)(4)(iv)(A)-(a)(9) [Reserved]. For guidance see Sec. 86.094-30.
(a)(10) and (a)(11) [Reserved]. For guidance see Sec. 86.004-30.
(a)(12) [Reserved]. For guidance see Sec. 86.094-30.
(a)(13) [Reserved]. For guidance see Sec. 86.095-30.
(a)(14) [Reserved]. For guidance see Sec. 86.094-30.
(a)(15)-(18) [Reserved]. For guidance see Sec. 86.096-30.
(a)(19) [Reserved]. For guidance see Sec. 86.098-30.
(a)(20) [Reserved]. For guidance see Sec. 86.001-30.
(a)(21) [Reserved]. For guidance see Sec. 86.004-30.
(b)(1) introductory text through (b)(1)(ii)(A) [Reserved]. For
guidance see Sec. 86.094-30.
(b)(1)(ii)(B) [Reserved]. For guidance see Sec. 86.004-30.
(b)(1)(ii)(C) [Reserved]. For guidance see Sec. 86.094-30.
(b)(1)(ii)(D) [Reserved]. For guidance see Sec. 86.004-30.
(b)(1)(iii) and (b)(1)(iv) [Reserved]. For guidance see Sec.
86.094-30.
(b)(2) [Reserved]. For guidance see Sec. 86.098-30.
(b)(3)-(b)(4)(i) [Reserved]. For guidance see Sec. 86.094-30.
(b)(4)(ii) introductory text [Reserved]. For guidance see Sec.
86.098-30.
(b)(4)(ii)(A) [Reserved]. For guidance see Sec. 86.094-30.
(b)(4)(ii)(B)-(b)(4)(iv) [Reserved]. For guidance see Sec. 86.098-
30.
(b)(5)-(e) [Reserved]. For guidance see Sec. 86.094-30.
(f) For engine families required to have an OBD system and meant
for applications less than or equal to 14,000 pounds GVWR,
certification will not be granted if, for any test vehicle approved by
the Administrator in consultation with the manufacturer, the
malfunction indicator light does not activate under any of the
following circumstances, unless the manufacturer can demonstrate that
any identified OBD problems discovered during the Administrator's
evaluation will be corrected on production vehicles.
(f)(1)(i) Otto-cycle. [Reserved]. For guidance see Sec. 86.004-30.
(f)(1)(ii) Diesel.
(A) If monitored for emissions performance--a reduction catalyst is
replaced with a deteriorated or defective catalyst, or an electronic
simulation of such, resulting in exhaust NOX emissions
exceeding the applicable NOX FEL+0.3 g/bhp-hr. Also if
monitored for emissions performance--an oxidation catalyst is replaced
with a deteriorated or defective catalyst, or an electronic simulation
of such, resulting in exhaust NMHC emissions exceeding 2.5 times the
applicable NMHC standard.
(B) If monitored for performance--a particulate trap is replaced
with a deteriorated or defective trap, or an electronic simulation of
such, resulting in either exhaust PM emissions exceeding the applicable
FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is higher; or, exhaust
NMHC emissions exceeding 2.5 times the applicable NMHC standard. Also,
if monitored for performance--a particulate trap is replaced with a
catastrophically failed trap or a simulation of such.
(f)(2) [Reserved]. For guidance see Sec. 86.004-30.
(f)(3)(i) Oxygen sensors and air-fuel ratio sensors downstream of
aftertreatment devices.
(f)(3)(i)(A) [Reserved]. For guidance see Sec. 86.007-30.
(f)(3)(i)(B) Diesel. If so equipped, any oxygen sensor or air-fuel
ratio sensor located downstream of aftertreatment devices is replaced
with a deteriorated or defective sensor, or an electronic simulation of
such, resulting in exhaust emissions exceeding any of the following
levels: the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM,
whichever is higher; or, the applicable NOX FEL+0.3 g/bhp-
hr; or, 2.5 times the applicable NMHC standard.
(ii) Oxygen sensors and air-fuel ratio sensors upstream of
aftertreatment devices.
(f)(3)(ii)(A) [Reserved]. For guidance see Sec. 86.007-30.
(f)(3)(ii)(B) Diesel. If so equipped, any oxygen sensor or air-fuel
ratio sensor located upstream of aftertreatment devices is replaced
with a deteriorated or defective sensor, or an electronic simulation of
such, resulting in exhaust emissions exceeding any of the following
levels: the applicable PM FEL+0.02 g/bhp-hr or 0.03 g/bhp-hr PM,
whichever is higher; or, the applicable NOX FEL+0.3 g/bhp-
hr; or, 2.5 times the applicable NMHC standard; or, 2.5 times the
applicable CO standard.
(iii) NOX sensors.
(f)(3)(iii)(A) [Reserved]. For guidance see Sec. 86.007-30.
(f)(3)(iii)(B) Diesel. If so equipped, any NOX sensor is
replaced with a deteriorated or defective sensor, or an electronic
simulation of such, resulting in exhaust emissions exceeding any of the
following levels: the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr
PM, whichever is higher; or, the applicable NOX FEL+0.3 g/
bhp-hr.
(f)(4) [Reserved]. For guidance see Sec. 86.004-30.
(f)(5)(i) [Reserved]. For guidance see Sec. 86.007-30.
(f)(5)(ii) Diesel. A malfunction condition is induced in any
emission-related engine system or component, including but not
necessarily limited to, the exhaust gas recirculation (EGR) system, if
equipped, and the fuel control system, singularly resulting in exhaust
emissions exceeding any of the following levels: the applicable PM
FEL+0.02 g/bhp-hr or 0.03 g/bhp-hr PM, whichever is higher; or, the
applicable NOX FEL+0.3 g/bhp-hr; or, 2.5 times the
applicable NMHC standard; or, 2.5 times the applicable CO standard.
(f)(6) [Reserved]. For guidance see Sec. 86.004-30.
9. Section 86.010-38 is added to subpart A to read as follows:
Sec. 86.010-38 Maintenance instructions.
This Section 86.010-38 includes text that specifies requirements
that differ from those specified in Sec. 86.007-38. Where a paragraph
in Sec. 86.096-38, or Sec. 86.004-38, or Sec. 86.007-38 is identical
and applicable to Sec. 86.010-38, this may be indicated by specifying
the corresponding paragraph and the statement ``[Reserved]. For
guidance see Sec. 86.096-38,'' ``[Reserved]. For guidance
[[Page 3322]]
see or Sec. 86.004-38, '' or ``[Reserved]. For guidance see Sec.
86.007-38.''
(a)-(f) [Reserved]. For guidance see Sec. 86.004-38.
(g) [Reserved]. For guidance see Sec. 86.096-38. For incorporation
by reference see Sec. Sec. 86.1 and 86.096-38.
(h) [Reserved]. For guidance see Sec. 86.004-38.
(i) [Reserved]. For guidance see Sec. 86.007-38.
(j) Emission control diagnostic service information for heavy-duty
engines used in vehicles over 14,000 pounds gross vehicle weight (GVW)
(1) Manufacturers of heavy-duty engines used in applications
weighing more than 14,000 pounds gross vehicle weight (GVW) that are
subject to the applicable OBD requirements of this subpart A are
subject to the provisions of this paragraph (j) beginning in the 2010
model year. The provisions of this paragraph (j) apply only to those
heavy-duty engines subject to the applicable OBD requirements.
(2) Upon Administrator approval, manufacturers may alternatively
comply with all service information and tool provisions found in Sec.
86.096-38 that are applicable to 1996 and subsequent vehicles weighing
less than 14,000 pounds gross vehicle weight (GVW).
(3) General Requirements
(i) Manufacturers shall furnish or cause to be furnished to any
person engaged in the repairing or servicing of heavy-duty engines, or
the Administrator upon request, any and all information needed to make
use of the on-board diagnostic system and such other information,
including instructions for making emission-related diagnosis and
repairs, including but not limited to service manuals, technical
service bulletins, recall service information, bi-directional control
information, and training information, unless such information is
protected by section 208(c) as a trade secret. No such information may
be withheld under section 208(c) of the Act if that information is
provided (directly or indirectly) by the manufacturer to franchised
dealers or other persons engaged in the repair, diagnosing, or
servicing of heavy-duty engines.
(ii) Definitions. The following definitions apply for this
paragraph (j):
(A) Aftermarket service provider means any individual or business
engaged in the diagnosis, service, and repair of a heavy-duty engine,
who is not directly affiliated with a manufacturer or manufacturer
franchised dealership.
(B) Bi-directional control means the capability of a diagnostic
tool to send messages on the data bus that temporarily overrides the
module's control over a sensor or actuator and gives control to the
diagnostic tool operator. Bi-directional controls do not create
permanent changes to engine or component calibrations.
(C) Data stream information means information (i.e., messages and
parameters) originated within the engine by a module or intelligent
sensors (i.e., a sensor that contains and is ontrolled by its own
module) and transmitted between a network of modules and/or intelligent
sensors connected in parallel with either one or more communication
wires. The information is broadcast over the communication wires for
use by the OBD system to gather information on emissions-related
components or systems and from other engine modules that may impact
emissions. For the purposes of this section, data stream information
does not include engine calibration related information, or any data
stream information from systems or modules that do not impact
emissions.
(D) Emissions-related information means any information related to
the diagnosis, service, and repair of emissions-related components.
Emissions-related information includes, but is not limited to,
information regarding any system, component or part of an engine that
controls emissions and any system, component and/or part associated
with the engine, including, but not limited to: the engine, the fuel
system and ignition system; information for any system, component or
part that is likely to impact emissions, and any other information
specified by the Administrator to be relevant to the diagnosis and
repair of an emissions-related problem; any other information specified
by the Administrator to be relevant for the diagnosis and repair of an
emissions-related failure found through an evaluation of vehicles in-
use and after such finding has been communicated to the affected
manufacturer(s).
(E) Emissions-related training information means any information
related training or instruction for the purpose of the diagnosis,
service, and repair of emissions-related components.
(F) Enhanced service and repair information means information which
is specific for an original equipment manufacturer's brand of tools and
equipment. This includes computer or anti-theft system initialization
information necessary for the completion of any emissions-related
repair on engines that employ integral security systems.
(G) Equipment and Tool Company means a registered equipment or
software company either public or private that is engaged in, or plans
to engage in, the manufacture of scan tool reprogramming equipment or
software.
(H) Generic service and repair information means information which
is not specific for an original equipment manufacturer's brand of tools
and equipment.
(I) Indirect information means any information that is not
specifically contained in the service literature, but is contained in
items such as tools or equipment provided to franchised dealers (or
others). This includes computer or anti-theft system initialization
information necessary for the completion of any emissions-related
repair on engines that employ integral security systems.
(J) Intermediary means any individual or entity, other than an
original equipment manufacturer, which provides service or equipment to
aftermarket service providers.
(K) Manufacturer franchised dealership means any service provider
with which a manufacturer has a direct business relationship.
(L) Third party information provider means any individual or
entity, other than an original equipment manufacturer, who consolidates
manufacturer service information and makes this information available
to aftermarket service providers.
(M) Third party training provider means any individual or entity,
other than an original equipment manufacturer who develops and/or
delivers instructional and educational material for training courses.
(4) Information dissemination. By July 1, 2010 each manufacturer
shall provide or cause to be provided to the persons specified in
paragraph (j)(3)(i) of this section and to any other interested parties
a manufacturer-specific World Wide Web site containing the information
specified in paragraph (j)(3)(i) of this section for 2010 and later
model year engines which have been certified to the OBD requirements
specified in Sec. 86.010-18 and are offered for sale; this requirement
does not apply to indirect information, including the information
specified in paragraphs (j)(13) through (j)(17) of this section. Upon
request and approval of the Administrator, manufacturers who can
demonstrate significant hardship in complying with this provision
within four months after the effective date may request an additional
six months lead time to meet this requirement. Each manufacturer Web
site shall:
(i) Provide access in full-text to all of the information specified
in paragraph (j)(5) of this section.
[[Page 3323]]
(ii) Be updated at the same time as manufacturer franchised
dealership World Wide Web sites.
(iii) Provide users with a description of the minimum computer
hardware and software needed by the user to access that manufacturer's
information (e.g., computer processor speed and operating system
software). This description shall appear when users first log-on to the
home page of the manufacturer's Web site.
(iv) Provide Short-Term (24 to 72 hours), Mid-Term (30 day period),
and Long-Term (365 day period) Web site subscription options to any
person specified in paragraph (j)(2)(i) of this section whereby the
user will be able to access the site, search for the information, and
purchase, view and print the information at a fair and reasonable cost
as specified in paragraph (j)(7) of this section for each of the
options. In addition, for each of the tiers, manufacturers are required
to make their entire site accessible for the respective period of time
and price. In other words, a manufacturer may not limit any or all of
the tiers to just one make or one model.
(v) Allow the user to search the manufacturer Web site by various
topics including but not limited to model, model year, key words or
phrases, etc., while allowing ready identification of the latest
calibration. Manufacturers who do not use model year to classify their
engines in their service information may use an alternate delineation
such as body series. Any manufacturer utilizing this flexibility shall
create a cross-reference to the corresponding model year and provide
this cross-reference on the manufacturer Web site home page.
(vi) Provide accessibility using common, readily available software
and shall not require the use of software, hardware, viewers, or
browsers that are not readily available to the general public.
Manufacturers shall also provide hyperlinks to any plug-ins, viewers or
browsers (e.g. Adobe Acrobat or Netscape) needed to access the
manufacturer Web site.
(vii) Allow simple hyper-linking to the manufacturer Web site from
Government Web sites and automotive-related Web sites.
(viii) Posses sufficient server capacity to allow ready access by
all users and has sufficient capacity to assure that all users may
obtain needed information without undue delay.
(ix) Correct or delete broken Web links on a weekly basis.
(x) Allow for Web site navigation that does not require a user to
return to the manufacturer home page or a search engine in order to
access a different portion of the site.
(xi) Allow users to print out any and all of the materials required
to be made available on the manufacturers Web site, including the
ability to print it at the user's location.
(5) Small volume provisions for information dissemination.
(i) Manufacturers with total annual sales of less than 5,000
engines shall have until July 1, 2011 to launch their individual Web
sites as required by paragraph (j)(4) of this section.
(ii) Manufacturers with total annual sales of less than 1,000
engines may, in lieu of meeting the requirement of paragraph (j)(4) of
this section, request the Administrator to approve an alternative
method by which the required emissions-related information can be
obtained by the persons specified in paragraph (j)(3)(i) of this
section.
(6) Required information. All information relevant to the diagnosis
and completion of emissions-related repairs shall be posted on
manufacturer Web sites. This excludes indirect information specified in
paragraphs (j)(7) and (j)(13) through (j)(17) of this section. To the
extent that this information does not already exist in some form for
their manufacturer franchised dealerships, manufacturers are required
to develop and make available the information required by this section
to both their manufacturer franchised dealerships and the aftermarket.
The required information includes, but is not limited to:
(i) Manuals, including subsystem and component manuals developed by
a manufacturer's third party supplier that are made available to
manufacturer franchised dealerships, technical service bulletins
(TSBs), recall service information, diagrams, charts, and training
materials. Manuals and other such service information from third party
suppliers are not required to be made available in full-text on
manufacturer Web sites as described in paragraph (j)(3) of this
section. Rather, manufacturers must make available on the manufacturer
Web site as required by paragraph (j)(3) of this section an index of
the relevant information and instructions on how to order such
information. In the alternate, a manufacturer can create a link from
its Web site to the Web site(s) of the third party supplier.
(ii) OBD system information which includes, but is not limited to,
the following:
(A) A general description of the operation of each monitor,
including a description of the parameter that is being monitored;
(B) A listing of all typical OBD diagnostic trouble codes
associated with each monitor;
(C) A description of the typical enabling conditions (either
generic or monitor-specific) for each monitor (if equipped) to execute
during engine operation, including, but not limited to, minimum and
maximum intake air and engine coolant temperature, speed range, and
time after engine startup. In addition, manufacturers shall list all
monitor-specific OBD drive cycle information for all major OBD monitors
as equipped including, but not limited to, catalyst, catalyst heater,
oxygen sensor, oxygen sensor heater, evaporative system, exhaust gas
re-circulation (EGR), secondary air, and air conditioning system.
Additionally, for diesel engines which also perform misfire, fuel
system and comprehensive component monitoring under specific driving
conditions (i.e., non-continuous monitoring; as opposed to spark
ignition engines that monitor these systems under all conditions or
continuous monitoring), the manufacturer shall make available monitor-
specific drive cycles for these monitors. Any manufacturer who develops
generic drive cycles, either in addition to, or instead of, monitor-
specific drive cycles shall also make these available in full-text on
manufacturer Web sites;
(D) A listing of each monitor sequence, execution frequency and
typical duration;
(E) A listing of typical malfunction thresholds for each monitor;
(F) For OBD parameters for specific engines that deviate from the
typical parameters, the OBD description shall indicate the deviation
and provide a separate listing of the typical values for those engines;
(G) Identification and scaling information necessary to interpret
and understand data available through Diagnostic Message 8 pursuant to
SAE Recommended Practice J1939-73, Application Layer--Diagnostics,
revised June 2001 or through Service/Mode $06 pursuant to SAE
Recommended Practice J1979, E/E Diagnostic Test Modes--Equivalent to
ISO/DIS 15031-5: April 30, 2002. These documents are Incorporated by
Reference in Sec. 86.1.
(H) Algorithms, look-up tables, or any values associated with look-
up tables are not required to be made available.
(iii) Any information regarding any system, component, or part of a
engine monitored by the OBD system that could in a failure mode cause
the OBD system to illuminate the malfunction indicator light (MIL);
(iv) Manufacturer-specific emissions-related diagnostic trouble
codes (DTCs)
[[Page 3324]]
and any related service bulletins, trouble shooting guides, and/or
repair procedures associated with these manufacturer-specific DTCs; and
(v) Information regarding how to obtain the information needed to
perform reinitialization of any computer or anti-theft system following
an emissions-related repair.
(7) Anti-theft System Initialization Information. Computer or anti-
theft system initialization information and/or related tools necessary
for the proper installation of on-board computers or necessary for the
completion of any emissions-related repair on engines that employ
integral security systems or the repair or replacement of any other
emission-related part shall be made available at a fair and reasonable
cost to the persons specified in paragraph (j)(3)(i) of this section.
(i) Except as provided under paragraph (j)(7)(ii) of this section,
manufacturers must make this information available to persons specified
in paragraph (j)(3)(i) of this section, such that such persons will not
need any special tools or manufacturer-specific scan tools to perform
the initialization. Manufacturers may make such information available
through, for example, generic aftermarket tools, a pass-through device,
or inexpensive manufacturer specific cables.
(ii) A manufacturer may request Administrator approval for an
alternative means to re-initialize engines for some or all model years
through the 2013 model year by 90 days following the effective date of
the final rule. The Administrator shall approve the request only after
the following conditions have been met:
(A) The manufacturer must demonstrate that the availability of such
information to aftermarket service providers would significantly
increase the risk of theft.
(B) The manufacturer must make available a reasonable alternative
means to install or repair computers, or to otherwise repair or replace
an emission-related part.
(C) Any alternative means proposed by a manufacturer cannot require
aftermarket technicians to use a manufacturer franchised dealership to
obtain information or special tools to re-initialize the anti-theft
system. All information must come directly from the manufacturer or a
single manufacturer-specified designee.
(D) Any alternative means proposed by a manufacturer must be
available to aftermarket technicians at a fair and reasonable price.
(E) Any alternative must be available to aftermarket technicians
within twenty-four hours of the initial request.
(F) Any alternative must not require the purchase of a special tool
or tools, including manufacturer-specific tools, to complete this
repair. Alternatives may include lease of such tools, but only for
appropriately minimal cost.
(G) In lieu of leasing their manufacturer-specific tool to meet
this requirement, a manufacturer may also choose to release the
necessary information to equipment and tool manufacturers for
incorporation into aftermarket scan tools. Any manufacturer choosing
this option must release the information to equipment and tool
manufacturers within 60 days of Administrator approval.
(8) Cost of required information.
(i) All information required to be made available by this section,
shall be made available at a fair and reasonable price. In determining
whether a price is fair and reasonable, consideration may be given to
relevant factors, including, but not limited to, the following:
(A) The net cost to the manufacturer franchised dealerships for
similar information obtained from manufacturers, less any discounts,
rebates, or other incentive programs;
(B) The cost to the manufacturer for preparing and distributing the
information, excluding any research and development costs incurred in
designing and implementing, upgrading or altering the onboard computer
and its software or any other engine part or component. Amortized
capital costs for the preparation and distribution of the information
may be included;
(C) The price charged by other manufacturers for similar
information;
(D) The price charged by manufacturers for similar information
prior to the launch of manufacturer Web sites;
(E) The ability of the average aftermarket technician or shop to
afford the information;
(F) The means by which the information is distributed;
(G) The extent to which the information is used, which includes the
number of users, and frequency, duration, and volume of use; and
(H) Inflation.
(ii) Manufacturers must submit to EPA a request for approval of
their pricing structure for their Web sites and amounts to be charged
for the information required to be made available under paragraphs
(j)(4) and (j)(6) of this section at least 180 days in advance of the
launch of the web site. Subsequent to the approval of the manufacturer
Web site pricing structure, manufacturers shall notify EPA upon the
increase in price of any one or all of the subscription options of 20
percent or more above the previously approved price, taking inflation
into account.
(A) The manufacturer shall submit a request to EPA that sets forth
a detailed description of the pricing structure and amounts, and
support for the position that the pricing structure and amounts are
fair and reasonable by addressing, at a minimum, each of the factors
specified in paragraph (j)(8)(i) of this section.
(B) EPA will act upon on the request within180 days following
receipt of a complete request or following receipt of any additional
information requested by EPA.
(C) EPA may decide not to approve, or to withdraw approval for a
manufacturer's pricing structure and amounts based on a conclusion that
this pricing structure and/or amounts are not, or are no longer, fair
and reasonable, by sending written notice to the manufacturer
explaining the basis for this decision.
(D) In the case of a decision by EPA not to approve or to withdraw
approval, the manufacturer shall within three months following notice
of this decision, obtain EPA approval for a revised pricing structure
and amounts by following the approval process described in this
paragraph.
(9) Unavailable information. Any information which is not provided
at a fair and reasonable price shall be considered unavailable, in
violation of these regulations and section 202(m)(5) of the Clean Air
Act.
(10) Third party information providers. By January 1, 2011
manufacturers shall, for model year 2010 and later engines, make
available to third-party information providers as defined in paragraph
(j)(3)(ii) of this section with whom they engage in licensing or
business arrangements;
(i) The required emissions-related information as specified in
paragraph (j)(6) of this section either:
(A) Directly in electronic format such as diskette or CD-ROM using
non-proprietary software, in English; or
(B) Indirectly via a Web site other than that required by paragraph
(j)(4) of this section;
(ii) For any manufacturer who utilizes an automated process in
their manufacturer-specific scan tool for diagnostic fault trees, the
data schema, detail specifications, including category types/codes and
engine codes, and data format/content structure of the diagnostic
trouble trees.
(iii) Manufacturers can satisfy the requirement of paragraph
(j)(10)(ii) of this section by making available
[[Page 3325]]
diagnostic trouble trees on their manufacturer Web sites in full-text.
(iv) Manufacturers are not responsible for the accuracy of the
information distributed by third parties. However, where manufacturers
charge information intermediaries for information, whether through
licensing agreements or other arrangements, manufacturers are
responsible for inaccuracies contained in the information they provide
to third party information providers.
(11) Required emissions-related training information. By January 1,
2011, for emissions-related training information, manufacturers shall:
(i) Video tape or otherwise duplicate and make available for sale
on manufacturer Web sites within 30 days after transmission any
emissions-related training courses provided to manufacturer franchised
dealerships via the Internet or satellite transmission;
(ii) Provide on the manufacturer Web site an index of all
emissions-related training information available for purchase by
aftermarket service providers for 2010 and newer engines. The required
information must be made available for purchase within 3 months of
model introduction and then must be made available at the same time it
is made available to manufacturer franchised dealerships, whichever is
earlier. The index shall describe the title of the course or
instructional session, the cost of the video tape or duplicate, and
information on how to order the item(s) from the manufacturer Web site.
All of the items available must be shipped within 24 hours of the order
being placed and are to made available at a fair and reasonable price
as described in paragraph (j)(8) of this section. Manufacturers unable
to meet the 24 hour shipping requirement under circumstances where
orders exceed supply and additional time is needed by the distributor
to reproduce the item being ordered, may exceed the 24 hour shipping
requirement, but in no instance can take longer than 14 days to ship
the item.
(iii) Provide access to third party training providers as defined
in paragraph (j)(3)(ii) of this section all emission-related training
courses transmitted via satellite or Internet offered to their
manufacturer franchised dealerships. Manufacturers may not charge
unreasonable up-front fees to third party training providers for this
access, but may require a royalty, percentage, or other arranged fee
based on per-use enrollment/subscription basis. Manufacturers may take
reasonable steps to protect any copyrighted information and are not
required to provide this information to parties that do not agree to
such steps.
(12) Timeliness and maintenance of information dissemination.
(i) Subsequent to the initial launch of the manufacturer's Web
site, manufacturers must make the information required under paragraph
(j)(6) of this section available on their Web site within six months of
model introduction, or at the same time it is made available to
manufacturer franchised dealerships. After this six month period, the
information must be available and updated on the manufacturer Web site
at the same time that the updated information is made available to
manufacturer franchised dealerships, except as otherwise specified in
this section.
(ii) Archived information. Manufacturers must maintain the required
information on their Web sites in full-text as defined in paragraph
(j)(6) of this section for a minimum of 15 years after model
introduction. Subsequent to this fifteen year period, manufacturers may
archive the information in the manufacturer's format of choice and
provide an index of the archived information on the manufacturer Web
site and how it can be obtained by interested parties. Manufacturers
shall index their available information with a title that adequately
describes the contents of the document to which it refers.
Manufacturers may allow for the ordering of information directly from
their Web site, or from a Web site hyperlinked to the manufacturer Web
site. In the alternate, manufacturers shall list a phone number and
address where aftermarket service providers can call or write to obtain
the desired information. Manufacturers must also provide the price of
each item listed, as well as the price of items ordered on a
subscription basis. To the extent that any additional information is
added or changed for these model years, manufacturers shall update the
index as appropriate. Manufacturers will be responsible for ensuring
that their information distributors do so within one regular business
day of receiving the order. Items that are less than 20 pages (e.g.
technical service bulletins) shall be faxed to the requestor and
distributors are required to deliver the information overnight if
requested and paid for by the ordering party. Archived information must
be made available on demand and at a fair and reasonable price.
(13) Recalibration Information.
(i) Manufacturers shall make available to the persons specified in
paragraph (j)(3)(i) of this section all emissions-related recalibration
or reprogramming events (including driveability reprogramming events
that may affect emissions) in the format of their choice at the same
time they are made available to manufacturer franchised dealerships.
This requirement takes effect on July 1, 2010.
(ii) Manufacturers shall provide persons specified in paragraph
(j)(3)(i) of this section with an efficient and cost-effective method
for identifying whether the calibrations on engines are the latest to
be issued. This requirement takes effect on July 1, 2010.
(iii) For all 2010 and later OBD engines equipped with
reprogramming capability, manufacturers shall comply with either SAE
J2534, ``Recommended Practice for Pass-Thru Vehicle Programming'' ,
December 2004, or the Technology and Maintenance Council's (TMC)
Recommended Practice RP1210A. ``WindowsTM Communication
API'' , July 1999. These documents are Incorporated by Reference in
Sec. 86.1.
(iv) For model years 2010 and later, manufacturers shall make
available to aftermarket service providers the necessary manufacturer-
specific software applications and calibrations needed to initiate
pass-through reprogramming. This software shall be able to run on a
standard personal computer that utilizes standard operating systems as
specified in either J2534 or RP1210A.
(v) Manufacturers may take any reasonable business precautions
necessary to protect proprietary business information and are not
required to provide this information to any party that does not agree
to these reasonable business precautions. The requirements to make
hardware available and to release the information to equipment and tool
companies takes effect on July 1, 2010, and within 3 months of model
introduction for all new model years.
(14) Generic and enhanced information for scan tools. By July 1,
2010, manufacturers shall make available to equipment and tool
companies all generic and enhanced service information including bi-
directional control and data stream information as defined in paragraph
(j)(4)(ii) of this section. This requirement applies for 2010 and later
model year engines.
(i) The information required by this paragraph (j)(14) shall be
provided electronically using common document formats to equipment and
tool companies with whom they have appropriate licensing, contractual,
and/or confidentiality arrangements. To the extent that a central
repository for this
[[Page 3326]]
information (e.g. the TEK-NET library developed by the Equipment and
Tool Institute) is used to warehouse this information, the
Administrator shall have free unrestricted access. In addition,
information required by this paragraph (j)(14) shall be made available
to equipment and tool companies who are not otherwise members of any
central repository and shall have access if the non-members have
arranged for the appropriate licensing, contractual and/or
confidentiality arrangements with the manufacturer and/or a central
repository.
(ii) In addition to the generic and enhanced information defined in
paragraph (j)(3)(ii) of this section, manufacturers shall also make
available the following information necessary for developing generic
diagnostic scan tools:
(A) The physical hardware requirements for data communication (e.g.
system voltage requirements, cable terminals/pins, connections such as
RS232 or USB, wires, etc.)
(B) Electronic Control Unit (ECU) data communication (e.g. serial
data protocols, transmission speed or baud rate, bit timing
requirements, etc),
(C) Information on the application physical interface (API) or
layers. (i.e., processing algorithms or software design descriptions
for procedures such as connection, initialization, and termination),
(D) Engine application information or any other related service
information such as special pins and voltages or additional connectors
that require enablement and specifications for the enablement.
(iii) Any manufacturer who utilizes an automated process in their
manufacturer-specific scan tool for diagnostic fault trees shall make
available to equipment and tool companies the data schema, detail
specifications, including category types/codes and codes, and data
format/content structure of the diagnostic trouble trees.
(iv) Manufacturers can satisfy the requirement of paragraph
(j)(14)(iii) of this section by making available diagnostic trouble
trees on their manufacturer Web sites in full-text.
(v) Manufacturers shall make all required information available to
the requesting equipment and tool company within 14 days after the
request to purchase has been made unless the manufacturer requests
Administrator approval to refuse to disclose such information to the
requesting company or requests Administrator approval for additional
time to comply. After receipt of a request and consultation with the
affected parties, the Administrator shall either grant or refuse the
petition based on the evidence submitted during the consultation
process:
(A) If the evidence demonstrates that the engine manufacturer has a
reasonably based belief that the requesting equipment and tool company
could not produce safe and functionally accurate tools that would not
cause damage to the engine, the petition for non-disclosure will be
granted. Engine manufacturers are not required to provide data stream
and bi-directional control information that would permit an equipment
and tool company's products to modify an EPA-certified engine or
transmission configuration.
(B) If the evidence does not demonstrate that the engine
manufacturer has a reasonably-based belief that the requesting
equipment and tool company could not produce safe and functionally
accurate tools that would not cause damage to the engine, the petition
for non-disclosure will be denied and the engine manufacturer, as
applicable, shall make the requested information available to the
requesting equipment and tool company within 2 days of the denial.
(vi) If the manufacturer submits a request for Administrator
approval for additional time, and satisfactorily demonstrates to the
Administrator that the engine manufacturer is able to comply but
requires additional time within which to do so, the Administrator shall
grant the request and provide additional time to fully and
expeditiously comply.
(vii) Manufacturers may require that tools using information
covered under paragraph (j)(14) of this section comply with the
Component Identifier message specified in SAE J1939-71 as Parameter
Group Number (PGN) 65249 (including the message parameter's make,
model, and serial number) and the SAE J1939-81 Address Claim PGN.
(15) Availability of manufacturer-specific scan tools.
Manufacturers shall make available for sale to the persons specified in
paragraph (j)(3)(i) of this section their own manufacturer-specific
diagnostic tools at a fair and reasonable cost. These tools shall also
be made available in a timely fashion either through the manufacturer
Web site or through a manufacturer-designated intermediary.
Manufacturers shall ship purchased tools in a timely manner after a
request and training, if any, has been completed. Any required training
materials and classes must be made available at a fair and reasonable
price. Manufacturers who develop different versions of one or more of
their diagnostic tools that are used in whole or in part for emission-
related diagnosis and repair shall also insure that all emission-
related diagnosis and repair information is available for sale to the
aftermarket at a fair and reasonable cost. Factors for determining fair
and reasonable cost include, but are not limited to:
(i) The net cost to the manufacturer's franchised dealerships for
similar tools obtained from manufacturers, less any discounts, rebates,
or other incentive programs;
(ii) The cost to the manufacturer for preparing and distributing
the tools, excluding any research and development costs;
(iii) The price charged by other manufacturers of similar sizes for
similar tools;
(iv) The capabilities and functionality of the manufacturer tool;
(v) The means by which the tools are distributed;
(vi) Inflation;
(vii) The ability of aftermarket technicians and shops to afford
the tools. Manufacturers shall provide technical support to aftermarket
service providers for the tools described in this section, either
themselves or through a third-party of their choice.
(16) Changing content of manufacturer-specific scan tools.
Manufacturers who opt to remove non-emissions related content from
their manufacturer-specific scan tools and sell them to the persons
specified in paragraph (j)(3)(i) of this section shall adjust the cost
of the tool accordingly lower to reflect the decreased value of the
scan tool. All emissions-related content that remains in the
manufacturer-specific tool shall be identical to the information that
is contained in the complete version of the manufacturer specific tool.
Any manufacturer who wishes to implement this option must request
approval from the Administrator prior to the introduction of the tool
into commerce.
(17) Reference Materials. Manufacturers shall conform with the
following Society of Automotive Engineers (SAE) standards. These
documents are incorporated by reference in Sec. 86.1.
(i) For Web-based delivery of service information, manufacturers
shall comply with SAE Recommended Practice J2403, Medium/Heavy-Duty E/E
Systems Diagnosis Nomenclature; August 2004. This recommended practice
standardizes various terms, abbreviations, and acronyms associated with
on-board diagnostics. Manufacturers shall comply with SAE J2403
beginning with the Model Year 2013.
[[Page 3327]]
(ii) For identification and scaling information necessary to
interpret and understand data available through Diagnostic Message 8,
manufacturers shall comply with SAE Recommended Practice J1939-73,
Application Layer--Diagnostics, revised June 2001. In the alternate,
manufacturers may comply with Service/Mode $06 pursuant to SAE
Recommended Practice J1979, E/E Diagnostic Test Modes--Equivalent to
ISO/DIS 15031-5: April 30, 2002. These recommended practices describe
the implementation of diagnostic test modes for emissions related test
data. Manufacturers shall comply with either SAE J1939-73 or SAE J1979
beginning with Model Year 2013. These recommended practices describe
the implementation of diagnostic test modes for emissions related test
data.
(iii) For pass-thru reprogramming capabilities, manufacturers shall
comply with Technology and Maintenance Council's (TMC) Recommended
Practice RP1210A, ``WindowsTM Communication API'' , July
1999. In the alternate, manufacturers may comply with SAE J2534,
Recommended Practice for Pass-Thru Vehicle Programming, December 2004.
These recommended practices provide technical specifications and
information that manufacturers must supply to equipment and tool
companies to develop aftermarket pass-thru reprogramming tools.
Manufacturers shall comply with either RP1210A or SAE J2534 beginning
with Model Year 2013.
(18) Reporting Requirements. Performance reports that adequately
demonstrate that each manufacturer's Web site meets the information
requirements outlined in paragraphs (j)(6)(i) through (j)(6)(vi) of
this section shall be submitted to the Administrator annually or upon
request by the Administrator. These reports shall indicate the
performance and effectiveness of the Web sites by using commonly used
Internet statistics (e.g., successful requests, frequency of use,
number of subscriptions purchased, etc.) Manufacturers shall provide to
the Administrator reports on an annual basis within 30 days of the end
of the calendar year. These annual reports shall be submitted to the
Administrator electronically utilizing non-proprietary software in the
format as agreed to by the Administrator and the manufacturers.
(19) Prohibited Acts, Liability and Remedies.
(i) It is a prohibited act for any person to fail to promptly
provide or cause a failure to promptly provide information as required
by this paragraph (j), or to otherwise fail to comply or cause a
failure to comply with any provision of this subsection.
(ii) Any person who fails or causes the failure to comply with any
provision of this paragraph (j) is liable for a violation of that
provision. A corporation is presumed liable for any violations of this
subpart that are committed by any of its subsidiaries, affiliates or
parents that are substantially owned by it or substantially under its
control.
(iii) Any person who violates a provision of this paragraph (j)
shall be subject to a civil penalty of not more than $31,500 per day
for each violation. This maximum penalty is shown for calendar year
2002. Maximum penalty limits for later years may be set higher based on
the Consumer Price Index, as specified in 40 CFR part 19. In addition,
such person shall be liable for all other remedies set forth in Title
II of the Clean Air Act, remedies pertaining to provisions of Title II
of the Clean Air Act, or other applicable provisions of law.
10. Section 86.013-2 is added to Subpart A to read as follows:
Sec. 86.013-2 Definitions.
The definitions of Sec. 86.004-2 continue to apply to 2004 and
later model year vehicles, and the definitions of Sec. 86.010-2
continue to apply to 2010 and later model year vehicles. The
definitions listed in this section apply beginning with the 2013 model
year.
Onboard Diagnostics (OBD) group means a combination of engines,
engine families, or engine ratings that use the same OBD strategies and
similar calibrations.
11. Section 86.013-17 is added to Subpart A to read as follows:
Sec. 86.013-17 On-board Diagnostics for engines used in applications
less than or equal to 14,000 pounds GVWR.
Section 86.013-17 includes text that specifies requirements that
differ from Sec. 86.005-17, Sec. 86.007-17, and Sec. 86.010-17.
Where a paragraph in Sec. 86.005-17 or Sec. 86.007-17 or Sec.
86.010-17 is identical and applicable to Sec. 86.013-17, this may be
indicated by specifying the corresponding paragraph and the statement
``[Reserved]. For guidance see Sec. 86.005-17.'' or ``[Reserved]. For
guidance see Sec. 86.007-17.'' or ``[Reserved]. For guidance see Sec.
86.010-17.''
(a) through (b)(1)(i) [Reserved]. For guidance see Sec. 86.010-17.
(b)(1)(ii) Diesel.
(A) If equipped, reduction catalyst deterioration or malfunction
before it results in exhaust NOX emissions exceeding the
applicable NOX FEL+0.3 g/bhp-hr. If equipped, oxidation
catalyst deterioration or malfunction before it results in exhaust NMHC
emissions exceeding 2 times the applicable NMHC standard. These
catalyst monitoring requirements need not be done if the manufacturer
can demonstrate that deterioration or malfunction of the system will
not result in exceedance of the threshold.
(B) If equipped, diesel particulate trap deterioration or
malfunction before it results in exhaust emissions exceeding any of the
following levels: the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr
PM, whichever is higher; or, exhaust NMHC emissions exceeding 2 times
the applicable NMHC standard. Catastrophic failure of the particulate
trap must also be detected. In addition, the absence of the particulate
trap or the trapping substrate must be detected.
(b)(2) [Reserved]. For guidance see Sec. 86.005-17.
(b)(3)(i) Oxygen sensors and air-fuel ratio sensors downstream of
aftertreatment devices.
(A) Otto-cycle. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is
higher; or, the applicable NOX FEL+0.3 g/bhp-hr; or, 2 times
the applicable NMHC standard.
(ii) Oxygen sensors and air-fuel ratio sensors upstream of
aftertreatment devices.
(A) Otto-cycle. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.02 g/bhp-hr or 0.03 g/bhp-hr PM, whichever is
higher; or, the applicable NOX FEL+0.3 g/bhp-hr; or, 2 times
the applicable NMHC standard; or, 2 times the applicable CO standard.
(iii) NOX sensors.
(A) Otto-cycle. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NMHC, NOX or CO.
(B) Diesel. If equipped, sensor deterioration or malfunction
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is
higher; or, the applicable NOX FEL+0.3 g/bhp-hr.
[[Page 3328]]
(b)(4) [Reserved]. For guidance see Sec. 86.005-17.
(b)(5) Other emission control systems and components.
(i) Otto-cycle. Any deterioration or malfunction occurring in an
engine system or component directly intended to control emissions,
including but not necessarily limited to, the exhaust gas recirculation
(EGR) system, if equipped, the secondary air system, if equipped, and
the fuel control system, singularly resulting in exhaust emissions
exceeding 1.5 times the applicable emission standard or FEL for NMHC,
NOX or CO. For engines equipped with a secondary air system,
a functional check, as described in Sec. 86.005-17(b)(6), may satisfy
the requirements of this paragraph (b)(5) provided the manufacturer can
demonstrate that deterioration of the flow distribution system is
unlikely. This demonstration is subject to Administrator approval and,
if the demonstration and associated functional check are approved, the
diagnostic system must indicate a malfunction when some degree of
secondary airflow is not detectable in the exhaust system during the
check. For engines equipped with positive crankcase ventilation (PCV),
monitoring of the PCV system is not necessary provided the manufacturer
can demonstrate to the Administrator's satisfaction that the PCV system
is unlikely to fail.
(ii) Diesel. Any deterioration or malfunction occurring in an
engine system or component directly intended to control emissions,
including but not necessarily limited to, the exhaust gas recirculation
(EGR) system, if equipped, and the fuel control system, singularly
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM FEL+0.02 g/bhp-hr or 0.03 g/bhp-hr PM, whichever is
higher; or, the applicable NOX FEL+0.3 g/bhp-hr; or, 2 times
the applicable NMHC standard; or, 2 times the applicable CO standard. A
functional check, as described in Sec. 86.005-17(b)(6), may satisfy the
requirements of this paragraph (b)(5) provided the manufacturer can
demonstrate that a malfunction would not cause emissions to exceed the
applicable levels. This demonstration is subject to Administrator
approval. For engines equipped with crankcase ventilation (CV),
monitoring of the CV system is not necessary provided the manufacturer
can demonstrate to the Administrator's satisfaction that the CV system
is unlikely to fail.
(b)(6) through (j) [Reserved]. For guidance see Sec. 86.010-17.
(k) [Reserved.]
12. Section 86.013-18 is added to Subpart A to read as follows:
Sec. 86.013-18 On-board Diagnostics for engines used in applications
greater than 14,000 pounds GVWR.
Section 86.013-18 includes text that specifies requirements that
differ from Sec. 86.010-18. Where a paragraph in Sec. 86.010-18 is
identical and applicable to Sec. 86.013-18, this may be indicated by
specifying the corresponding paragraph and the statement ``[Reserved].
For guidance see Sec. 86.010-18.'' However, where a paragraph in Sec.
86.010-18 is identical and applicable to Sec. 86.013-18, and there
appears the statement ``[Reserved]. For guidance see Sec. 86.010-18,''
it shall be understood that any referenced tables within Sec. 86.010-
18 shall actually refer to the applicable table shown in Sec. 86.013-
18.
(a) General. All heavy-duty engines intended for use in a heavy-
duty vehicle weighing more than 14,000 pounds GVWR must be equipped
with an on-board diagnostic (OBD) system capable of monitoring all
emission-related engine systems or components during the life of the
engine. The OBD system is required to detect all malfunctions specified
in paragraphs (g), and (i) of this section and paragraph (h) of Sec.
86.010-18 although the OBD system is not required to use a unique
monitor to detect each of those malfunctions.
(a)(1) [Reserved]. For guidance see Sec. 86.010-18.
(a)(2) The OBD system must be equipped with a standardized data
link connector to provide access to the stored DTCs as specified in
paragraph (k)(2) of this section.
(a)(3) and (a)(4) [Reserved]. For guidance see Sec. 86.010-18.
(b) Malfunction indicator light (MIL) and Diagnostic Trouble Codes
(DTC). The OBD system must incorporate a malfunction indicator light
(MIL) or equivalent and must store specific types of diagnostic trouble
codes (DTC).
(1) MIL specifications.
(i) The MIL must be located on the driver's side instrument panel
and be of sufficient illumination and location to be readily visible
under all lighting conditions. The MIL must be amber (yellow) in color;
the use of red for the OBD-related MIL is prohibited. More than one
general purpose malfunction indicator light for emission-related
problems shall not be used; separate specific purpose warning lights
(e.g., brake system, fasten seat belt, oil pressure, etc.) are
permitted. When activated, the MIL must display the engine symbol
designated as F01 by the International Standards Organization (ISO) in
``Road vehicles--Symbols for controls, indicators and tell-tales,'' ISO
2575:2004.
(b)(1)(ii) through (b)(1)(iv) [Reserved]. For guidance see Sec.
86.010-18.
(b)(1)(v) The MIL required by this paragraph (b) must not be used
in any other way than is specified in this section.
(b)(2) [Reserved]. For guidance see Sec. 86.010-18.
(b)(3) MIL deactivation and DTC erasure protocol.
(i) Deactivating the MIL. Except as otherwise provided for in
paragraph (g)(2)(iv)(E) of this section and Sec. 86.010-
18(g)(6)(iv)(B) for diesel misfire malfunctions and empty reductant
tanks, and paragraphs (h)(1)(iv)(F), (h)(2)(viii), and (h)(7)(iv)(B) of
Sec. 86.010-18 for gasoline fuel system, misfire, and evaporative
system malfunctions, once the MIL has been activated, it may be
deactivated after three subsequent sequential drive cycles during which
the monitoring system responsible for activating the MIL functions and
the previously detected malfunction is no longer present and provided
no other malfunction has been detected that would independently
activate the MIL according to the requirements outlined in Sec.
86.010-18(b)(2).
(b)(3)(ii) through (b)(4) [Reserved.] For guidance see Sec.
86.010-18.
(c) Monitoring conditions. The OBD system must monitor and detect
the malfunctions specified in paragraphs (g) and (i) of this section
and Sec. 86.010-18(h) under the following general monitoring
conditions. The more specific monitoring conditions of paragraph (d) of
this section are sometimes required according to the provisions of
paragraphs (g) and (i) of this section and Sec. 86.010-18(h).
(1) As specifically provided for in paragraphs (g) and (i) of this
section and Sec. 86.010-18(h), the monitoring conditions for detecting
malfunctions must be technically necessary to ensure robust detection
of malfunctions (e.g. avoid false passes and false indications of
malfunctions); designed to ensure monitoring will occur under
conditions that may reasonably be expected to be encountered in normal
vehicle operation and normal vehicle use; and, designed to ensure
monitoring will occur during the FTP transient test cycle contained in
Appendix I paragraph (f), of this part, or similar drive cycle as
approved by the Administrator.
(c)(2) [Reserved]. For guidance see Sec. 86.010-18.
(c)(3) Manufacturers may request approval to define monitoring
conditions that are not encountered during the FTP cycle as required in
paragraph (c)(1) of this section. In
[[Page 3329]]
evaluating the manufacturer's request, the Administrator will consider
the degree to which the requirement to run during the FTP transient
cycle restricts monitoring during in-use operation, the technical
necessity for defining monitoring conditions that are not encountered
during the FTP cycle, data and/or an engineering evaluation submitted
by the manufacturer that demonstrate that the component/system does not
normally function during the FTP, whether monitoring is otherwise not
feasible during the FTP cycle, and/or the ability of the manufacturer
to demonstrate that the monitoring conditions satisfy the minimum
acceptable in-use monitor performance ratio requirement as defined in
paragraph (d)(1)(ii) of this section.
(d) through (d)(1)(i) [Reserved]. For guidance see Sec. 86.010-18.
(d)(1)(ii) Manufacturers must define monitoring conditions that, in
addition to meeting the criteria in paragraph (c)(1) of this section
and Sec. 86.010-18(d) through (d)(1)(i), ensure that the monitor
yields an in-use performance ratio (as defined in Sec. 86.010-18(d)(2)
that meets or exceeds the minimum acceptable in-use monitor performance
ratio of 0.100 for all monitors specifically required in paragraphs (g)
and (i) of this section and Sec. 86.010-18(h) to meet the monitoring
condition requirements in Sec. 86.010-(18)(d)(1)(i).
(iii) If the most reliable monitoring method developed requires a
lower ratio for a specific monitor than that specified in paragraph
(d)(1)(ii) of this section, the Administrator may lower the minimum
acceptable in-use monitoring performance ratio.
(d)(2) through (d)(3)(iv) [Reserved]. For guidance see Sec.
86.010-18.
(d)(3)(v) Manufacturers that use alternative statistical MIL
activation protocols as allowed in Sec. 86.010-18(b)(2)(iii) for any
of the monitors requiring a numerator, are required to increment the
numerator(s) appropriately. The manufacturer may be required to provide
supporting data and/or engineering analyses demonstrating both the
equivalence of their incrementing approach to the incrementing
specified in this paragraph (d)(3) for monitors using the standard MIL
activation protocol, and the overall equivalence of the incrementing
approach in determining that the minimum acceptable in-use performance
ratio of paragraph (d)(1)(ii) of this section has been satisfied.
(d)(4) through (f) [Reserved]. For guidance see Sec. 86.010-18.
(g) OBD monitoring requirements for diesel-fueled/compression-
ignition engines. The following table shows the thresholds at which
point certain components or systems, as specified in this paragraph
(g), are considered malfunctioning.
Table 1.--OBD Emissions Thresholds for Diesel-Fueled/Compression Ignition Engines Meant for Engines Placed in
Applications Greater Than 14,000 Pounds GVWR (g/bhp-hr)
----------------------------------------------------------------------------------------------------------------
Sec. 86.010-
Component 18 reference NMHC CO NOX PM
----------------------------------------------------------------------------------------------------------------
NMHC catalyst system........... (g)(5)......... 2x............. ............... ............... ...........
NOX aftertreatment system...... (g)(6)......... ............... ............... +0.3........... ...........
(g)(7)
Diesel particulate filter (DPF) (g)(8)......... 2x............. ............... ............... 0.05/+0.04
system.
Air-fuel ratio sensors upstream (g)(9)......... 2x............. 2x............. +0.3........... 0.03/+0.02
of aftertreatment devices.
Air-fuel ratio sensors (g)(9)......... 2x............. ............... +0.3........... 0.05/+0.04
downstream of aftertreatment
devices.
NOX sensors.................... (g)(9)......... ............... ............... +0.3........... 0.05/+0.04
``Other monitors'' with (g)(1)......... 2x............. 2x............. +0.3........... 0.03/+0.02
emissions thresholds. (g)(2).........
(g)(3)
(g)(4)
(g)(10)
----------------------------------------------------------------------------------------------------------------
Notes: FEL=Family Emissions Limit; 2x std means a multiple of 2 times the applicable emissions standard; +0.3
means the standard or FEL plus 0.3; 0.05/+0.04 means an absolute level of 0.05 or an additive level of the
standard or FEL plus 0.04, whichever level is higher; these emissions thresholds apply to the monitoring
requirements of paragraph (g) of this Sec. 86.013-18.
(1) Fuel system monitoring.
(g)(1)(i) through (g)(1)(iii)(A) [Reserved]. For guidance see Sec.
86.010-18.
(g)(1)(iii)(B) The manufacturer must define the monitoring
conditions for malfunctions identified in Sec. 86.010-18(g)(1)(ii)(B)
and (g)(1)(ii)(C) and Table 1 of paragraph (g) of this section in
accordance with paragraphs (c) and (d) of this section.
(iv) Fuel system MIL activation and DTC storage. The MIL must
activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(2) Engine misfire monitoring.
(g)(2)(i) [Reserved]. For guidance see Sec. 86.010-18.
(g)(2)(ii) Engine misfire malfunction criteria.
(A) The OBD system must be capable of detecting misfire occurring
in one or more cylinders. To the extent possible without adding
hardware for this specific purpose, the OBD system must also identify
the specific misfiring cylinder. If more than one cylinder is
continuously misfiring, a separate DTC must be stored indicating that
multiple cylinders are misfiring. When identifying multiple cylinder
misfire, the OBD system is not required to identify individually
through separate DTCs each of the continuously misfiring cylinders.
(B) On engines equipped with sensors that can detect combustion or
combustion quality (e.g., for use in engines with homogeneous charge
compression ignition (HCCI) control systems), the OBD system must
detect a misfire malfunction causing emissions to exceed the applicable
thresholds for ``other monitors'' shown in Table 1 of this paragraph
(g). To determine what level of misfire would cause emissions to exceed
the applicable emissions thresholds, the manufacturer must determine
the percentage of misfire evaluated in 1,000 revolution increments that
would cause emissions from an emission durability demonstration engine
to exceed the emissions thresholds if the percentage of misfire were
present from the beginning of the test. To establish this percentage of
misfire, the manufacturer must use misfire events occurring at equally
spaced, complete engine cycle intervals, across randomly selected
cylinders throughout each 1,000-revolution increment. If this
percentage
[[Page 3330]]
of misfire is determined to be lower than one percent, the manufacturer
may set the malfunction criteria at one percent. Any misfire
malfunction must be detected if the percentage of misfire established
via this testing is exceeded regardless of the pattern of misfire
events (e.g., random, equally spaced, continuous). The manufacturer may
employ other revolution increments besides the 1,000 revolution
increment. To do so, the manufacturer must demonstrate that the
strategy is equally effective and timely in detecting misfire.
(iii) Engine misfire monitoring conditions.
(g)(2)(iii)(A) and (g)(2)(iii)(B) [Reserved]. For guidance see
Sec. 86.010-18.
(g)(2)(iii)(C) For engines equipped with sensors that can detect
combustion or combustion quality the OBD system must monitor
continuously for engine misfire under all positive torque engine speed
and load conditions. If a monitoring system cannot detect all misfire
patterns under all required engine speed and load conditions, the
manufacturer may request that the Administrator approve the monitoring
system nonetheless. In evaluating the manufacturer's request, the
Administrator will consider the following factors: the magnitude of the
region(s) in which misfire detection is limited; the degree to which
misfire detection is limited in the region(s) (i.e., the probability of
detection of misfire events); the frequency with which said region(s)
are expected to be encountered in-use; the type of misfire patterns for
which misfire detection is troublesome; and demonstration that the
monitoring technology employed is not inherently incapable of detecting
misfire under required conditions (i.e., compliance can be achieved on
other engines). The evaluation will be based on the following misfire
patterns: equally spaced misfire occurring on randomly selected
cylinders; single cylinder continuous misfire; and, paired cylinder
(cylinders firing at the same crank angle) continuous misfire.
(iv) Engine misfire MIL activation and DTC storage.
(A) General requirements for MIL activation and DTC storage are set
forth in paragraph (b) of this section.
(B) For engines equipped with sensors that can detect combustion or
combustion quality, upon detection of the percentage of misfire
specified in paragraph (g)(2)(ii)(B) of this section, the following
criteria shall apply for MIL activation and DTC storage: A pending DTC
must be stored no later than after the fourth exceedance of the
percentage of misfire specified in paragraph (g)(2)(ii) of this section
during a single drive cycle; if a pending fault code has been stored,
the OBD system must activate the MIL and store a MIL-on DTC within 10
seconds if the percentage of misfire specified in paragraph (g)(2)(ii)
of this section is again exceeded four times during the drive cycle
immediately following storage of the pending DTC, regardless of the
conditions encountered during the drive cycle, or on the next drive
cycle in which similar conditions are encountered to those that were
occurring when the pending DTC was stored. Similar conditions means an
engine speed within 375 rpm, engine load within 20 percent, and the
same warm up status (i.e., cold or hot). The Administrator may approve
other definitions of similar conditions based on comparable timeliness
and reliability in detecting similar engine operation. The pending DTC
may be erased at the end of the next drive cycle in which similar
conditions are encountered to those that were occurring when the
pending DTC was stored provided the specified percentage of misfire was
not again exceeded. The pending DTC may also be erased if similar
conditions are not encountered during the 80 drive cycles immediately
following initial detection of the malfunction.
(C) For engines equipped with sensors that can detect combustion or
combustion quality, the OBD system must store and erase freeze frame
conditions either in conjunction with storing and erasing a pending DTC
or in conjunction with storing and erasing a MIL-on DTC. If freeze
frame conditions are stored for a malfunction other than a misfire
malfunction when a DTC is stored as specified in paragraph
(g)(2)(iv)(B) of this section, the stored freeze frame information must
be replaced with the freeze frame information regarding the misfire
malfunction.
(D) For engines equipped with sensors that can detect combustion or
combustion quality, upon detection of misfire according to paragraph
(g)(2)(iv)(B) of this section, the OBD system must also store the
following engine conditions: engine speed, load, and warm up status of
the first misfire event that resulted in the storage of the pending
DTC.
(E) For engines equipped with sensors that can detect combustion or
combustion quality, the MIL may be deactivated after three sequential
drive cycles in which similar conditions have been encountered without
an exceedance of the specified percentage of misfire.
(3) EGR system monitoring.
(g)(3)(i) and (g)(3)(ii) [Reserved]. For guidance see Sec. 86.010-
18.
(g)(3)(iii) EGR system monitoring conditions.
(g)(3)(iii)(A) [Reserved]. For guidance see Sec. 86.010-18.
(g)(3)(iii)(B) The manufacturer must define the monitoring
conditions for malfunctions identified in Sec. 86.010-18(g)(3)(ii)(C)
and Table 1 of paragragh (g) of this section in accordance with
paragraphs (c) and (d) of this section, with the exception that
monitoring must occur every time the monitoring conditions are met
during the drive cycle rather than once per drive cycle as required in
Sec. 86.010-18(c)(2). For purposes of tracking and reporting as
required in Sec. 86.010-18(d) through (d)(1)(i), all monitors used to
detect malfunctions identified in Sec. 86.010-18(g)(3)(ii)(C) and
Table 1 of paragraph (g) of this section must be tracked separately but
reported as a single set of values as specified in Sec. 86.010-
18(e)(1)(iii).
(C) The manufacturer must define the monitoring conditions for
malfunctions identified in Sec. 86.010-18(g)(3)(ii)(E) and Table 1 of
paragraph (g) of this section in accordance with paragraphs (c) and (d)
of this section. For purposes of tracking and reporting as required in
Sec. 86.010-18(d) through (d)(1)(i), all monitors used to detect
malfunctions identified in Sec. 86.010-18(g)(3)(ii)(E) and Table 1 of
paragraph (g) of this section must be tracked separately but reported
as a single set of values as specified in Sec. 86.010-18(e)(1)(iii).
(g)(3)(iii)(D) [Reserved]. For guidance see Sec. 86.010-18.
(g)(3)(iv) EGR system MIL activation and DTC storage. The MIL must
activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(4) Turbo boost control system monitoring.
(g)(4)(i) and (g)(4)(ii) [Reserved]. For guidance see Sec. 86.010-
18.
(g)(4)(iii) Turbo boost control system monitoring conditions.
(g)(4)(iii)(A) [Reserved]. For guidance see Sec. 86.010-18.
(g)(iii)(3)(B) The manufacturer must define the monitoring
conditions for malfunctions identified in Sec. 86.010-18(g)(4)(ii)(C)
and Table 1 of paragraph (g) of this section in accordance with
paragraphs (c) and (d) of this section, with the exception that
monitoring must occur every time the monitoring conditions are met
during the drive cycle rather than once per drive cycle as required in
Sec. 86.010-18(c)(2). For purposes of tracking and reporting as
required in Sec. 86.010-18(d) through (d)(1)(i), all monitors used to
detect
[[Page 3331]]
malfunctions identified in Sec. 86.010-18(g)(4)(ii)(C) and Table 1 of
paragraph (g) of this section must be tracked separately but reported
as a single set of values as specified in Sec. 86.010-18(e)(1)(iii).
(C) The manufacturer must define the monitoring conditions for
malfunctions identified in Sec. 86.010-18(g)(4)(ii)(E) and Table 1 of
paragraph (g) of this section in accordance with paragraphs (c) and (d)
of this section. For purposes of tracking and reporting as required in
Sec. 86.010-18(d) through (d)(1)(i), all monitors used to detect
malfunctions identified in Sec. 86.010-18(g)(4)(ii)(E) and Table 1 of
paragraph (g) of this section must be tracked separately but reported
as a single set of values as specified in Sec. 86.010-18(e)(1)(iii).
(iv) Turbo boost system MIL activation and DTC storage. The MIL
must activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(5) NMHC converting catalyst monitoring.
(g)(5)(i) and (g)(5)(ii) [Reserved]. For guidance see Sec. 86.010-
18.
(g)(5)(iii) NMHC converting catalyst monitoring conditions. The
manufacturer must define the monitoring conditions for malfunctions
identified in Sec. 86.010-18(g)(5)(ii)(A) and (g)(5)(ii)(B) and Table
1 of paragraph (g) of this section in accordance with paragraphs (c)
and (d) of this section. For purposes of tracking and reporting as
required in Sec. 86.010-18(d) through (d)(1)(i), all monitors used to
detect malfunctions identified in Sec. 86.010-18(g)(5)(ii)(A) and
(g)(5)(ii)(B) and Table 1 of paragraph (g) of this section must be
tracked separately but reported as a single set of values as specified
in Sec. 86.010-18(e)(1)(iii).
(iv) NMHC converting catalyst MIL activation and DTC storage. The
MIL must activate and DTCs must be stored according to the provisions
of paragraph (b) of this section. The monitoring method for the NMHC
converting catalyst(s) must be capable of detecting all instances,
except diagnostic self-clearing, when a catalyst DTC has been erased
but the catalyst has not been replaced (e.g., catalyst over-temperature
histogram approaches are not acceptable).
(6) Selective catalytic reduction (SCR) and lean NOX
catalyst monitoring.
(g)(6)(i) and (g)(6)(ii) [Reserved]. For guidance see Sec. 86.010-
18
(g)(6)(iii) SCR and lean NOX catalyst monitoring
conditions.
(A) The manufacturers must define the monitoring conditions for
malfunctions identified in Sec. 86.010-18(g)(6)(ii)(A) and Table 1 of
paragraph (g) of this section in accordance with paragraphs (c) and (d)
of this section. For purposes of tracking and reporting as required in
Sec. 86.010-18(d) through (d)(1)(i), all monitors used to detect
malfunctions identified in Sec. 86.010-18(g)(6)(ii)(A) and Table 1 of
paragraph (g) of this section must be tracked separately but reported
as a single set of values as specified in Sec. 86.010-18(e)(1)(iii).
(g)(6)(iii)(B) [Reserved]. For guidance see Sec. 86.010-18.
(g)(6)(iv) SCR and lean NOX catalyst MIL activation and
DTC storage.
(A) For malfunctions identified in Sec. 86.010-18(g)(6)(ii)(A) and
Table 1 of paragraph (g) of this section, the MIL must activate and
DTCs must be stored according to the provisions of paragraph (b) of
this section.
(g)(6)(iv)(B) and (g)(6)(iv)(C) [Reserved]. For guidance see Sec.
86.010-18.
(g)(7) NOX adsorber system monitoring.
(g)(7)(i) and (g)(7)(ii) [Reserved]. For guidance see Sec. 86.010-
18.
(g)(7)(iii) NOX adsorber system monitoring conditions.
(A) The manufacturer must define the monitoring conditions for
malfunctions identified in Sec. 86.010-18(g)(7)(ii)(A) and Table 1 of
paragraph (g) of this section in accordance with paragraphs (c) and (d)
of this section. For purposes of tracking and reporting as required in
Sec. 86.010-18(d) through (d)(1)(i), all monitors used to detect
malfunctions identified in Sec. 86.010-18(g)(7)(ii)(A) and Table 1 of
paragraph (g) of this section must be tracked separately but reported
as a single set of values as specified in of Sec. 86.010-
18(e)(1)(iii).
(g)(7)(iii)(B) [Reserved]. For guidance see Sec. 86.010-18.
(g)(7)(iv) NOX adsorber system MIL activation and DTC storage. The
MIL must activate and DTCs must be stored according to the provisions
of paragraph (b) of this section.
(8) Diesel particulate filter (DPF) system monitoring.
(g)(8)(i) and (g)(8)(ii) [Reserved]. For guidance see Sec. 86.010-
18.
(g)(8)(iii) DPF monitoring conditions. The manufacturer must define
the monitoring conditions for malfunctions identified in Sec. 86.010-
18(g)(8)(ii) and Table 1 of paragraph (g) of this section in accordance
with paragraphs (c) and (d) of this section, with the exception that
monitoring must occur every time the monitoring conditions are met
during the drive cycle rather than once per drive cycle as required in
Sec. 86.010-18(c)(2). For purposes of tracking and reporting as
required in Sec. 86.010-18(d) through (d)(1)(i), all monitors used to
detect malfunctions identified in Sec. 86.010-18(g)(8)(ii) and Table 1
of paragraph (g) of this section must be tracked separately but
reported as a single set of values as specified in Sec. 86.010-
18(e)(1)(iii).
(iv) DPF system MIL activation and DTC storage. The MIL must
activate and DTCs must be stored according to the provisions of
paragraph (b) of this section.
(9) Exhaust gas sensor and sensor heater monitoring.
(g)(9)(i) through (g)(9)(vi) [Reserved]. For guidance see Sec.
86.010-18.
(g)(9)(vii) Monitoring conditions for exhaust gas sensors.
(A) The manufacturer must define the monitoring conditions for
malfunctions identified in Sec. 86.010-18(g)(9)(ii)(A),
(g)(9)(iii)(A), and (g)(9)(iv)(A) (i.e., sensor performance) and Table
1 of paragraph (g) of this section in accordance with paragraphs (c)
and (d) of this section. For purposes of tracking and reporting as
required in Sec. 86.010-18(d) through (d)(1)(i), all monitors used to
detect malfunctions identified in Sec. 86.010-18(g)(9)(ii)(A),
(g)(9)(iii)(A), and(g)(9)(iv)(A) and Table 1 of paragraph (g) of this
section must be tracked separately but reported as a single set of
values as specified in Sec. 86.010-18(e)(1)(iii).
(B) The manufacturer must define the monitoring conditions for
malfunctions identified in Sec. 86.010-18(g)(9)(ii)(D),
(g)(9)(iii)(D), and (g)(9)(iv)(D) (i.e., monitoring function) and Table
1 of paragraph (g) of this section in accordance with paragraphs (c)
and (d) of this section with the exception that monitoring must occur
every time the monitoring conditions are met during the drive cycle
rather than once per drive cycle as required in Sec. 86.010-18(c)(2).
(g)(9)(vii)(C) and (g)(9)(vii)(D) [Reserved]. For guidance see
Sec. 86.010-18.
(g)(9)(viii) Monitoring conditions for exhaust gas sensor heaters.
(A) The manufacturer must define monitoring conditions for
malfunctions identified in Sec. 86.010-18(g)(9)(A) (i.e., sensor
heater performance) and Table 1 of paragraph (g) of this section in
accordance with paragraphs (c) and (d) of this section.
(g)(9)(viii)(B) [Reserved]. For guidance see Sec. 86.010-18.
(g)(9)(ix) Exhaust gas sensor and sensor heater MIL activation and
DTC storage. The MIL must activate and DTCs must be stored according to
the provisions of paragraph (b) of this section.
(10) Variable valve timing (VVT) system monitoring.
[[Page 3332]]
(g)(10)(i) and (g)(10)(vii) [Reserved]. For guidance see Sec.
86.010-18.
(g)(10)(iii) VVT system monitoring conditions. Manufacturers must
define the monitoring conditions for VVT system malfunctions identified
in Sec. 86.010-18(g)(10)(ii) and Table 1 of paragraph (g) of this
section in accordance with paragraphs (c) and (d) of this section, with
the exception that monitoring must occur every time the monitoring
conditions are met during the drive cycle rather than once per drive
cycle as required in Sec. 86.010-18(c)(2). For purposes of tracking
and reporting as required in Sec. 86.010-18(d) through (d)(1)(i), all
monitors used to detect malfunctions identified in Sec. 86.010-
18(g)(10)(ii) and Table 1 of paragraph (g) of this section must be
tracked separately but reported as a single set of values as specified
in Sec. 86.010-18(d)(1)(iii).
(iv) VVT MIL activation and DTC storage. The MIL must activate and
DTCs must be stored according to the provisions of paragraph (b) of
this section.
(h) [Reserved]. For guidance see Sec. 86.010-18.
(i) OBD monitoring requirements for all engines.
(1) Engine cooling system monitoring.
(i)(1)(i) through (i)(1)(iii) [Reserved]. For guidance see Sec.
86.010-18.
(i)(1)(iv) Monitoring conditions for the thermostat.
(A) The manufacturer must define the monitoring conditions for
malfunctions identified in paragraph Sec. 86.010-18(i)(1)(ii)(A) and
Table 1 of paragraph (g) of this section in accordance with paragraph
(c) of this section. Additionally, except as provided for in Sec.
86.010-18(i)(1)(iv)(B) and (i)(1)(iv)(C), monitoring for malfunctions
identified in Sec. 86.010-18(i)(1)(ii)(A) and Table 1 of paragraph (g)
of this section must be conducted once per drive cycle on every drive
cycle in which the ECT sensor indicates, at engine start, a temperature
lower than the temperature established as the malfunction criteria in
Sec. 86.010-18(i)(1)(ii)(A) and Table 1 of paragraph (g) of this
section.
(i)(1)(iv)(B) and (i)(1)(iv)(C) [Reserved]. For guidance see Sec.
86.010-18.
(i)(1)(v) Monitoring conditions for the ECT sensor.
(i)(1)(v)(A) [Reserved]. For guidance see Sec. 86.010-18.
(i)(1)(v)(B) The manufacturer must define the monitoring conditions
for malfunctions identified in Sec. 86.010-18(i)(1)(iii)(B) and Table
1 of paragraph (g) of this section in accordance with paragraph (c) of
this section. Additionally, except as provided for in Sec. 86.010-
18(i)(1)(v)(D), monitoring for malfunctions identified in Sec. 86.010-
18(i)(1)(iii)(B) and Table 1 of paragraph (g) of this section must be
conducted once per drive cycle on every drive cycle in which the ECT
sensor indicates a temperature lower than the closed-loop enable
temperature at engine start (i.e., all engine start temperatures
greater than the ECT sensor out-of-range low temperature and less than
the closed-loop enable temperature).
(C) The manufacturer must define the monitoring conditions for
malfunctions identified in Sec. 86.010-18(i)(1)(iii)(C) and
(i)(1)(iii)(D) and Table 1 of paragraph (g) of this section in
accordance with paragraphs (c) and (d) of this section.
(i)(1)(v)(D) and (i)(1)(v)(E) [Reserved]. For guidance see Sec.
86.010-18.
(i)(1)(vi) Engine cooling system MIL activation and DTC storage.
The MIL must activate and DTCs must be stored according to the
provisions of paragraph (b) of this section.
(2) Crankcase ventilation (CV) system monitoring.
(i)(2)(i) and (i)(2)(ii) [Reserved]. For guidance see Sec. 86.010-
18.
(i)(2)(iii) Crankcase ventilation system monitoring conditions. The
manufacturer must define the monitoring conditions for malfunctions
identified in Sec. 86.010-18(i)(2)(ii) and Table 1 of paragraph (g) of
this section in accordance with paragraphs (c) and (d) of this section.
(iv) Crankcase ventilation system MIL activation and DTC storage.
The MIL must activate and DTCs must be stored according to the
provisions of paragraph (b) of this section. The stored DTC need not
identify specifically the CV system (e.g., a DTC for idle speed control
or fuel system monitoring can be stored) if the manufacturer can
demonstrate that additional monitoring hardware would be necessary to
make such an identification and provided the manufacturer's diagnostic
and repair procedures for the detected malfunction include directions
to check the integrity of the CV system.
(3) Comprehensive component monitoring.
(i) General. Except as provided for in paragraph (i)(4) of this
section, the OBD system must detect a malfunction of any electronic
engine component or system not otherwise described in paragraphs (g),
(i)(1), and (i)(2) of this section and Sec. 86.010-18(h) that either
provides input to (directly or indirectly, such components may include
the crank angle sensor, knock sensor, throttle position sensor, cam
position sensor, intake air temperature sensor, boost pressure sensor,
manifold pressure sensor, mass air flow sensor, exhaust temperature
sensor, exhaust pressure sensor, fuel pressure sensor, fuel composition
sensor of a flexible fuel vehicle, etc.) or receives commands from
(such components or systems may include the idle speed control system,
glow plug system, variable length intake manifold runner systems,
supercharger or turbocharger electronic components, heated fuel
preparation systems, the wait-to-start lamp on diesel applications, the
MIL, etc.) the onboard computer(s) and meets either of the criteria
described in Sec. 86.010-18(i)(3)(i)(A) and/or (i)(3)(i)(B). Note
that, for the purposes of this paragraph (i)(3), ``electronic engine
component or system'' does not include components that are driven by
the engine and are not related to the control of the fueling, air
handling, or emissions of the engine (e.g., PTO components, air
conditioning system components, and power steering components).
(i)(3)(i)(A) through (i)(3)(iii) [Reserved]. For guidance see Sec.
86.010-18.
(i)(3)(iv) Monitoring conditions for input components.
(i)(3)(iv)(A) [Reserved]. For guidance see Sec. 86.010-18.
(i)(3)(iv)(B) For input component rationality checks (where
applicable), the manufacturer must define the monitoring conditions for
detecting malfunctions in accordance with paragraphs (c) and (d) of
this section, with the exception that rationality checks must occur
every time the monitoring conditions are met during the drive cycle
rather than once per drive cycle as required in Sec. 86.010-18(c)(2).
(v) Monitoring conditions for output components/systems.
(i)(3)(v)(A) [Reserved]. For guidance see Sec. 86.010-18.
(i)(3)(v)(B) For output component/system functional checks, the
manufacturer must define the monitoring conditions for detecting
malfunctions in accordance with paragraphs (c) and (d) of this section.
Specifically for the idle control system, the manufacturer must define
the monitoring conditions for detecting malfunctions in accordance with
paragraphs (c) and (d) of this section, with the exception that
functional checks must occur every time the monitoring conditions are
met during the drive cycle rather than once per drive cycle as required
in Sec. 86.010-18(c)(2).
(vi) Comprehensive component MIL activation and DTC storage.
(A) Except as provided for in Sec. 86.010-18(i)(3)(vi)(B) and
(i)(3)(vi)(C), the MIL must activate and DTCs must be
[[Page 3333]]
stored according to the provisions of paragraph (b) of this section.
(i)(3)(vi)(B) and (i)(3)(vi)(C) [Reserved]. For guidance see Sec.
86.010-18.
(i)(4) Other emission control system monitoring.
(i) General. For other emission control systems that are either not
addressed in Sec. 86.010-18(h) and paragraphs (g) and (i)(1) through
(i)(3) of this section (e.g., hydrocarbon traps, homogeneous charge
compression ignition control systems), or addressed in paragraph (i)(3)
of this section but not corrected or compensated for by an adaptive
control system (e.g., swirl control valves), the manufacturer must
submit a plan for Administrator approval of the monitoring strategy,
malfunction criteria, and monitoring conditions prior to introduction
on a production engine. The plan must demonstrate the effectiveness of
the monitoring strategy, the malfunction criteria used, the monitoring
conditions required by the monitor, and, if applicable, the
determination that the requirements of Sec. 86.010-18(i)(4)(ii) are
satisfied.
(i)(4)(ii) through (i)(5)(v) [Reserved]. For guidance see Sec.
86.010-18.
(i)(6) Feedback control system monitoring. If the engine is
equipped with feedback control of any of the systems covered in
paragraphs (g) and (i) of this section and Sec. 86.010-18(h), then the
OBD system must detect as malfunctions the conditions specified in this
paragraph (i)(6) for each of the individual feedback controls.
(i)(6)(i) through (i)(6)(iv) [Reserved]. For guidance see Sec.
86.010-18.
(j) Production evaluation testing.
(1) Verification of standardization requirements.
(i) The manufacturer must perform testing to verify that production
vehicles meet the requirements of paragraphs (k)(3) and (k)(4) of this
section relevant to the proper communication of required emissions-
related messages to a SAE J1978/J1939 scan tool.
(ii) Selection of test vehicles.
(A) The manufacturer must perform this testing every model year on
ten unique production vehicles (i.e., engine rating and chassis
application combination) per engine family. If there are less than ten
unique production vehicles for a certain engine family, the
manufacturer must test each unique production vehicle in that engine
family. The manufacturer must perform this testing within either three
months of the start of engine production or one month of the start of
vehicle production, whichever is later. The manufacturer may request
approval to group multiple production vehicles together and test one
representative vehicle per group. To do so, the software and hardware
designed to comply with the standardization requirements of paragraph
(k) of this section (e.g., communication protocol message timing,
number of supported data stream parameters, engine and vehicle
communication network architecture) in the representative vehicle must
be identical to all others in the group and any differences in the
production vehicles cannot be relevant with respect to meeting the
criteria of paragraph (j)(1)(iv) of this section.
(B) For 2016 and subsequent model years, the required number of
vehicles to be tested shall be reduced to five per engine family
provided zero vehicles fail the testing required by paragraph (j)(1) of
this section for two consecutive years.
(C) For 2019 and subsequent model years, the required number of
vehicles to be tested shall be reduced to three per engine family
provided zero vehicles fail the testing required by paragraph (j)(1) of
this section for three consecutive years.
(D) The requirement for submittal of data from one or more of the
production vehicles shall be waived if data have been submitted
previously for all of the production vehicles. The manufacturer may
request approval to carry over data collected in previous model years.
To do so, the software and hardware designed to comply with the
standardization requirements of paragraph (k) of this section must be
identical to the previous model year and there must not have been other
hardware or software changes that affect compliance with the
standardization requirements.
(iii) Test equipment. For the testing required by paragraph (j)(1)
of this section, the manufacturer shall use an off-board device to
conduct the testing. The manufacturer must be able to show that the
off-board device is able to verify that the vehicles tested using the
device are able to perform all of the required functions in paragraph
(j)(1)(iv) of this section with any other off-board device designed and
built in accordance with the SAE J1978/J1939 generic scan tool
specifications.
(iv) Required testing. The testing must verify that communication
can be established properly between all emission-related on-board
computers and any SAE J1978/J1939 scan tool designed to adhere strictly
to the communication protocols allowed in paragraph (k)(3) of this
section. The testing must also verify that all emission-related
information is communicated properly between all emission-related on-
board computers and any SAE J1978/J1939 scan tool in accordance with
the requirements of paragraph (k) of this section and the applicable
ISO and SAE specifications including specifications for physical layer,
network layer, message structure, and message content. The testing must
also verify that the onboard computer(s) can properly respond to any
SAE J1978/J1939 scan tool request to clear emissions-related DTCs and
reset the ready status in accordance with paragraph (k)(4)(ix) of this
section. The testing must further verify that the following information
can be properly communicated to any SAE J1978/J1939 scan tool:
(A) The current ready status from all onboard computers required to
support ready status in accordance with SAE J1978/J1939-73 and
paragraph (k)(4)(i) of this section in the key-on, engine-off position
and while the engine is running.
(B) The MIL command status while a deactivated MIL is commanded and
while an activated MIL is commanded in accordance with SAE J1979/J1939
and paragraph (k)(4)(ii) of this section in the key-on, engine-off
position and while the engine is running, and in accordance with SAE
J1979/J1939 and Sec. 86.010-18(b)(1)(ii) during the MIL functional
check and, if applicable, (k)(4)(i)(C) of this section during the MIL
ready status check while the engine is off.
(C) All data stream parameters required in paragraph (k)(4)(ii) of
this section in accordance with SAE J1979/J1939 including, if
applicable, the proper identification of each data stream parameter as
supported in SAE J1979 (e.g., Mode/Service $01, PID $00).
(D) The CAL ID, CVN, and VIN as required by paragraphs (k)(4)(vi),
(k)(4)(vii), and (k)(4)(viii) of this section and in accordance with
SAE J1979/J1939.
(E) An emissions-related DTC (permanent, pending, MIL-on, previous-
MIL-on) in accordance with SAE J1979/J1939-73 (including the correct
indication of the number of stored DTCs (e.g., Mode/Service $01, PID
$01, Data A for SAE J1979)) and paragraph (k)(4)(iv) of this section.
(v) Reporting of results. The manufacturer must submit to the
Administrator the following, based on the results of the testing
required by paragraph (j)(1)(iv) of this section:
(A) If a variant meets all the requirements of paragraph (j)(1)(iv)
of this section, a statement specifying that the variant passed all the
tests. Upon request from the Administrator, the
[[Page 3334]]
detailed results of any such testing may have to be submitted.
(B) If any variant does not meet the requirements of paragraph
(j)(1)(iv) of this section, a written report detailing the problem(s)
identified and the manufacturer's proposed corrective action (if any)
to remedy the problem(s). This report must be submitted within one
month of testing the specific variant. The Administrator will consider
the proposed remedy and, if in disagreement, will work with the
manufacturer to propose an alternative remedy. Factors to be considered
by the Administrator in considering the proposed remedy will include
the severity of the problem(s), the ability of service technicians to
access the required diagnostic information, the impact on equipment and
tool manufacturers, and the amount of time prior to implementation of
the proposed corrective action.
(vi) Alternative testing protocols. Manufacturers may request
approval to use other testing protocols. To do so, the manufacturer
must demonstrate that the alternative testing methods and equipment
will provide an equivalent level of verification of compliance with the
standardization requirements as is required by paragraph (j)(1) of this
section.
(2) Verification of monitoring requirements.
(j)(2)(i) through (j)(2)(ii)(C) [Reserved]. For guidance see Sec.
86.010-18.
(j)(2)(iii) Evaluation requirements.
(A) The evaluation must demonstrate the ability of the OBD system
on the selected test vehicle to detect a malfunction, activate the MIL,
and, where applicable, store an appropriate DTC readable by a SAE
J1978/J1939 scan tool when a malfunction is present and the monitoring
conditions have been satisfied for each individual monitor required by
this section.
(j)(2)(iii)(B) through (j)(2)(iv) [Reserved]. For guidance see
Sec. 86.010-18.
(j)(3) Verification of in-use monitoring performance ratios.
(j)(3)(i) through (j)(3)(iii) [Reserved]. For guidance see Sec.
86.010-18.
(j)(3)(iv) For each monitoring performance group, the data must
include all of the in-use performance tracking data reported through
SAE J1979/J1939 (i.e., all numerators, denominators, the general
denominator, and the ignition cycle counter), the date the data were
collected, the odometer reading, the VIN, and the calibration ID.
(j)(3)(v) and (j)(3)(vi) [Reserved]. For guidance see Sec. 86.010-
18.
(k) Standardization requirements.
(k)(1) through (k)(1)(i)(B) [Reserved]. For guidance see Sec.
86.010-18.
(k)(1)(i)(C) SAE J1962 ``Diagnostic Connector--;Equivalent to ISO/
DIS 15031-3: December 14, 2001,'' April 2002.
(k)(1)(i)(D) through (k)(1)(ii)(A) [Reserved]. For guidance see
Sec. 86.010-18.
(k)(2) Diagnostic connector. A standard data link connector
conforming to SAE J1962 or SAE J1939-13 specifications (except as
provided for in paragraph (k)(2)(iii) of this section) must be included
in each vehicle.
(i) The connector must be located in the driver's side foot-well
region of the vehicle interior in the area bound by the driver's side
of the vehicle and the driver's side edge of the center console (or the
vehicle centerline if the vehicle does not have a center console) and
at a location no higher than the bottom of the steering wheel when in
the lowest adjustable position. The connector shall not be located on
or in the center console (i.e., neither on the horizontal faces near
the floor-mounted gear selector, parking brake lever, or cup-holders
nor on the vertical faces near the car stereo, climate system, or
navigation system controls). The location of the connector shall be
capable of being easily identified and accessed (e.g., to connect an
off-board tool). For vehicles equipped with a driver's side door, the
connector must be identified and accessed easily by someone standing
(or ``crouched'') on the ground outside the driver's side of the
vehicle with the driver's side door open. The Administrator may approve
an alternative location upon request from the manufacturer. In all
cases, the installation position of the connector must be both
identified and accessed easily by someone standing outside the vehicle
and protected from accidental damage during normal vehicle use.
(ii) If the connector is covered, the cover must be removable by
hand without the use of any tools and be labeled ``OBD'' to aid
technicians in identifying the location of the connector. Access to the
diagnostic connector shall not require opening or the removal of any
storage accessory (e.g., ashtray, coinbox). The label must clearly
identify that the connector is located behind the cover and is
consistent with language and/or symbols commonly used in the automobile
and/or heavy truck industry.
(iii) If the ISO 15765-4 communication protocol is used for the
required OBD standardized functions, the connector must meet the ``Type
A'' specifications of SAE J1962. Any pins in the connector that provide
electrical power must be properly fused to protect the integrity and
usefulness of the connector for diagnostic purposes and shall not
exceed 20.0 Volts DC regardless of the nominal vehicle system or
battery voltage (e.g., 12V, 24V, 42V).
(iv) If the SAE J1939 protocol is used for the required OBD
standardized functions, the connector must meet the specifications of
SAE J1939-13. Any pins in the connector that provide electrical power
must be properly fused to protect the integrity and usefulness of the
connector for diagnostic purposes.
(v) The manufacturer may equip engines/vehicles with additional
diagnostic connectors for manufacturer-specific purposes (i.e.,
purposes other than the required OBD functions). However, if the
additional connector conforms to the ``Type A'' specifications of SAE
J1962 or the specifications of SAE J1939-13 and is located in the
vehicle interior near the required connector as described in this
paragraph (k)(2) of this section, the connector(s) must be labeled
clearly to identify which connector is used to access the standardized
OBD information required by paragraph (k) of this section.
(3) Communications to a scan tool. All OBD control modules (e.g.,
engine, auxiliary emission control module) on a single vehicle must use
the same protocol for communication of required emission-related
messages from on-board to off-board network communications to a scan
tool meeting SAE J1978 specifications or designed to communicate with
an SAE J1939 network. Engine manufacturers shall not alter normal
operation of the engine emission control system due to the presence of
off-board test equipment accessing information required by this
paragraph (k). The OBD system must use one of the following
standardized protocols:
(i) ISO 15765-4. All required emission-related messages using this
protocol must use a 500 kbps baud rate.
(ii) SAE J1939. This protocol may only be used on vehicles with
diesel engines.
(4) Required emission related functions. The following standardized
functions must be implemented in accordance with the specifications in
SAE J1979 or SAE J1939 to allow for access to the required information
by a scan tool meeting SAE J1978 specifications or designed to
communicate with an SAE J1939 network:
(i) Ready status. In accordance with SAE J1979/J1939-73
specifications, the OBD system must indicate ``complete'' or ``not
complete'' for each of the installed monitored components and
[[Page 3335]]
systems identified in paragraphs (g), and (i)(3) of this section, and
paragraph (h) with the exception of Sec. 86.010-18(h)(4). All
components or systems identified in Sec. 86.010-18(h)(1) or (h)(2), or
(i)(3) of this section that are monitored continuously must always
indicate ``complete.'' Components or systems that are not subject to
being monitored continuously must immediately indicate ``complete''
upon the respective monitor(s) being executed fully and determining
that the component or system is not malfunctioning. A component or
system must also indicate ``complete'' if, after the requisite number
of decisions necessary for determining MIL status has been executed
fully, the monitor indicates a malfunction of the component or system.
The status for each of the monitored components or systems must
indicate ``not complete'' whenever diagnostic memory has been cleared
or erased by a means other than that allowed in paragraph (b) of this
section. Normal vehicle shut down (i.e., key-off/engine-off) shall not
cause the status to indicate ``not complete.''
(k)(4)(i)(A) [Reserved]. For guidance see Sec. 86.010-18.
(k)(4)(i)(B) For the evaporative system monitor, the ready status
must be set in accordance with this paragraph (k)(4)(i) when both the
functional check of the purge valve and, if applicable, the leak
detection monitor of the hole size specified in Sec. 86.010-
18(h)(7)(ii)(B) indicate that they are complete.
(C) If the manufacturer elects to indicate ready status through the
MIL in the key-on/engine-off position as provided for in Sec. 86.010-
18(b)(1)(iii), the ready status must be indicated in the following
manner: If the ready status for all monitored components or systems is
``complete,'' the MIL shall remain continuously activated in the key-
on/engine-off position for at least 10-20 seconds. If the ready status
for one or more of the monitored components or systems is ``not
complete,'' after at least 5 seconds of operation in the key-on/engine-
off position with the MIL activated continuously, the MIL shall blink
once per second for 5-10 seconds. The data stream value for MIL status
as required in paragraph (k)(4)(ii) of this section must indicate
``commanded off'' during this sequence unless the MIL has also been
``commanded on'' for a detected malfunction.
(ii) Data stream. The following signals must be made available on
demand through the standardized data link connector in accordance with
SAE J1979/J1939 specifications. The actual signal value must always be
used instead of a limp home value.
(k)(4)(ii)(A) through (k)(4)(ii)(C) [Reserved]. For guidance see
Sec. 86.010-18.
(k)(4)(iii) Freeze frame.
(A) ``Freeze frame'' information required to be stored pursuant to
Sec. 86.010-18(b)(2)(iv), (h)(1)(iv)(D), and (h)(2)(vi) must be made
available on demand through the standardized data link connector in
accordance with SAE J1979/J1939-73 specifications.
(k)(4)(iii)(B) [Reserved]. For guidance see Sec. 86.010-18.
(k)(4)(iii)(C) Only one frame of data is required to be recorded.
The manufacturer may choose to store additional frames provided that at
least the required frame can be read by a scan tool meeting SAE J1978
specifications or designed to communicate with an SAE J1939 network.
(iv) Diagnostic trouble codes.
(A) For all monitored components and systems, any stored pending,
MIL-on, and previous-MIL-on DTCs must be made available through the
diagnostic connector in a standardized format in accordance with SAE
J1939 or ISO 15765-4 specifications. Standardized DTCs conforming to
the applicable standardized specifications must be employed.
(k)(4)(iv)(B) and (k)(4)(iv)(C) [Reserved]. For guidance see Sec.
86.010-18.
(k)(4)(iv)(D) A pending or MIL-on DTC (as required in paragraphs
(g) and (i) of this section and Sec. 86.010-18(h)) must be stored and
available to an SAE J1978 or SAE J1939 scan tool within 10 seconds
after a monitor has determined that a malfunction or potential
malfunction has occurred. A permanent DTC must be stored and available
to an SAE J1978 or SAE J1939 scan tool no later than the end of an
ignition cycle in which the corresponding MIL-on DTC that caused MIL
activation has been stored.
(E) Pending DTCs for all components and systems (including those
monitored continuously and non-continuously) must be made available
through the diagnostic connector in accordance with the applicable
standard's specifications. A manufacturer using alternative statistical
protocols for MIL activation as allowed in Sec. 86.010-18(b)(2)(iii)
must submit the details of their protocol for setting pending DTCs. The
protocol must be, overall, equivalent to the requirements of this
paragraph (k)(4)(iv)(E) and provide service technicians with a quick
and accurate indication of a potential malfunction.
(F) Permanent DTC for all components and systems must be made
available through the diagnostic connector in a standardized format
that distinguishes permanent DTCs from pending DTCs, MIL-on DTCs, and
previous-MIL-on DTCs. A MIL-on DTC must be stored as a permanent DTC no
later than the end of the ignition cycle and subsequently at all times
that the MIL-on DTC is commanding the MIL on. Permanent DTCs must be
stored in non-volatile random access memory (NVRAM) and shall not be
erasable by any scan tool command or by disconnecting power to the on-
board computer. Permanent DTCs must be erasable if the engine control
module is reprogrammed and the ready status described in paragraph
(k)(4)(i) of this section for all monitored components and systems are
set to ``not complete.'' The OBD system must have the ability to store
a minimum of four current MIL-on DTCs as permanent DTCs in NVRAM. If
the number of MIL-on DTCs currently commanding activation of the MIL
exceeds the maximum number of permanent DTCs that can be stored, the
OBD system must store the earliest detected MIL-on DTC as permanent
DTC. If additional MIL-on DTCs are stored when the maximum number of
permanent DTCs is already stored in NVRAM, the OBD system shall not
replace any existing permanent DTC with the additional MIL-on DTCs.
(v) Test results.
(A) Except as provided for in Sec. 86.010-18(k)(4)(v)(G), for all
monitored components and systems identified in paragraph (g) of this
section and Sec. 86.010-18(h), results of the most recent monitoring
of the components and systems and the test limits established for
monitoring the respective components and systems must be stored and
available through the data link in accordance with the standardized
format specified in SAE J1979 (for engines using the ISO 15765-4
protocol) or SAE J1939.
(k)(4)(v)(B) [Reserved]. For guidance see Sec. 86.010-18.
(k)(4)(v)(C) The test results must be standardized such that the
name of the monitored component (e.g., catalyst bank 1) can be
identified by a generic scan tool and the test results and limits can
be scaled and reported by a generic scan tool with the appropriate
engineering units.
(k)(4)(v)(D) through (k)(4)(v)(G) [Reserved]. For guidance see
Sec. 86.010-18.
(k)(4)(vi) Software calibration identification (CAL ID). On all
engines, a single software calibration identification number (CAL ID)
for each monitor or emission critical control unit(s) must be made
available through the standardized data link connector in accordance
with the SAE J1979/J1939
[[Page 3336]]
specifications. A unique CAL ID must be used for every emission-related
calibration and/or software set having at least one bit of different
data from any other emission-related calibration and/or software set.
Control units coded with multiple emission or diagnostic calibrations
and/or software sets must indicate a unique CAL ID for each variant in
a manner that enables an off-board device to determine which variant is
being used by the vehicle. Control units that use a strategy that will
result in MIL activation if the incorrect variant is used (e.g.,
control units that contain variants for manual and automatic
transmissions but will activate the MIL if the selected variant does
not match the type of transmission mated to the engine) are not
required to use unique CAL IDs.
(vii) Software calibration verification number (CVN).
(A) All engines must use an algorithm to calculate a single
calibration verification number (CVN) that verifies the on-board
computer software integrity for each monitor or emission critical
control unit that is electronically reprogrammable. The CVN must be
made available through the standardized data link connector in
accordance with the SAE J1979/J1939 specifications. The CVN must
indicate whether the emission-related software and/or calibration data
are valid and applicable for the given vehicle and CAL ID.
(k)(4)(vii)(B) [Reserved]. For guidance see Sec. 86.010-18.
(k)(4)(vii)(C) The CVN must be calculated at least once per drive
cycle and stored until the CVN is subsequently updated. Except for
immediately after a reprogramming event or a non-volatile memory clear
or for the first 30 seconds of engine operation after a volatile memory
clear or battery disconnect, the stored value must be made available
through the data link connector to a generic scan tool in accordance
with SAE J1979/J1939 specifications. The stored CVN value shall not be
erased when DTC memory is erased by a generic scan tool in accordance
with SAE J1979/J1939 specifications or during normal vehicle shut down
(i.e., key-off/engine-off).
(D) The CVN and CAL ID combination information must be available
for all engines/vehicles in a standardized electronic format that
allows for off-board verification that the CVN is valid and appropriate
for a specific vehicle and CAL ID.
(viii) Vehicle identification number (VIN).
(A) All vehicles must have the vehicle identification number (VIN)
available in a standardized format through the standardized data link
connector in accordance with SAE J1979/J1939 specifications. Only one
electronic control unit per vehicle may report the VIN to an SAE J1978/
J1939 scan tool.
(k)(4)(viii)(B) [Reserved]. For guidance see Sec. 86.010-18.
(k)(4)(ix) Erasure of diagnostic information.
(A) For purposes of this paragraph (k)(4)(ix), ``emission-related
diagnostic information'' includes all of the following: ready status as
required by paragraph (k)(4)(i) of this section; data stream
information as required by paragraph (k)(4)(ii) of this section
including the number of stored MIL-on DTCs, distance traveled while MIL
activated, number of warm-up cycles since DTC memory last erased, and
distance traveled since DTC memory last erased; freeze frame
information as required by paragraph (k)(4)(iii) of this section;
pending, MIL-on, and previous-MIL-on DTCs as required by paragraph
(k)(4)(iv) of this section; and, test results as required by paragraph
(k)(4)(v) of this section.
(k)(4)(ix)(B) [Reserved]. For guidance see Sec. 86.010-18.
(k)(5) In-use performance ratio tracking requirements.
(i) For each monitor required in paragraphs (g) and (i) of this
section and Sec. 86.010-18(h) to separately report an in-use
performance ratio, manufacturers must implement software algorithms to
report a numerator and denominator in the standardized format specified
in this paragraph (k)(5) in accordance with the SAE J1979/J1939
specifications.
(ii) For the numerator, denominator, general denominator, and
ignition cycle counters required by Sec. 86.010-18(e), the following
numerical value specifications apply:
(A) Each number shall have a minimum value of zero and a maximum
value of 65,535 with a resolution of one.
(B) Each number shall be reset to zero only when a non-volatile
random access memory (NVRAM) reset occurs (e.g., reprogramming event)
or, if the numbers are stored in keep-alive memory (KAM), when KAM is
lost due to an interruption in electrical power to the control unit
(e.g., battery disconnect). Numbers shall not be reset to zero under
any other circumstances including when a scan tool command to clear
DTCs or reset KAM is received.
(C) To avoid overflow problems, if either the numerator or
denominator for a specific component reaches the maximum value of
65,535 2, both numbers shall be divided by two before
either is incremented again.
(D) To avoid overflow problems, if the ignition cycle counter
reaches the maximum value of 65,535 2, the ignition cycle
counter shall rollover and increment to zero on the next ignition
cycle.
(E) To avoid overflow problems, if the general denominator reaches
the maximum value of 65,535 2, the general denominator
shall rollover and increment to zero on the next drive cycle that meets
the general denominator definition.
(F) If a vehicle is not equipped with a component (e.g., oxygen
sensor bank 2, secondary air system), the corresponding numerator and
denominator for that specific component shall always be reported as
zero.
(iii) For the ratio required by Sec. 86.010-18(e), the following
numerical value specifications apply:
(A) The ratio shall have a minimum value of zero and a maximum
value of 7.99527 with a resolution of 0.000122.
(B) The ratio for a specific component shall be considered to be
zero whenever the corresponding numerator is equal to zero and the
corresponding denominator is not zero.
(C) The ratio for a specific component shall be considered to be
the maximum value of 7.99527 if the corresponding denominator is zero
or if the actual value of the numerator divided by the denominator
exceeds the maximum value of 7.99527.
(6) Engine run time tracking requirements.
(i) For all gasoline and diesel engines, the manufacturer must
implement software algorithms to track and report individually in a
standardized format the amount of time the engine has been operated in
the following conditions:
(A) Total engine run time.
(B) Total idle run time (with ``idle'' defined as accelerator pedal
released by the driver, vehicle speed less than or equal to one mile
per hour, engine speed greater than or equal to 50 to 150 rpm below the
normal, warmed-up idle speed (as determined in the drive position for
vehicles equipped with an automatic transmission), and power take-off
not active).
(C) Total run time with power take off active.
(ii) For each counter specified in paragraph (k)(6)(i) of this
section, the following numerical value specifications apply:
(A) Each number shall be a four-byte value with a minimum value of
zero, a resolution of one second per bit, and an accuracy of ten seconds per drive cycle.
[[Page 3337]]
(B) Each number shall be reset to zero only when a non-volatile
memory reset occurs (e.g., reprogramming event). Numbers shall not be
reset to zero under any other circumstances including when a scan tool
(generic or enhanced) command to clear fault codes or reset KAM is
received.
(C) To avoid overflow problems, if any of the individual counters
reach the maximum value, all counters shall be divided by two before
any are incremented again.
(D) The counters shall be made available to a generic scan tool in
accordance with the SAE J1979/J1939 specifications and may be rescaled
when transmitted, if required by the SAE specifications, from a
resolution of one second per bit to no more than three minutes per bit.
(l) Monitoring system demonstration requirements for certification.
(1) General.
(l)(1)(i) through (l)(1)(iii) [Reserved]. For guidance see Sec.
86.010-18.
(l)(2) Selection of test engines.
(l)(2)(i) [Reserved]. For guidance see Sec. 86.010-18.
(l)(2)(ii) A manufacturer certifying one to five engine families in
a given model year must provide emissions test data for a single test
engine from one engine rating. A manufacturer certifying six to ten
engine families in a given model year must provide emissions test data
for a single test engine from two different engine ratings. A
manufacturer certifying eleven or more engine families in a given model
year must provide emissions test data for a single test engine from
three different engine ratings. A manufacturer may forego submittal of
test data for one or more of these test engines if data have been
submitted previously for all of the engine ratings and/or if all
requirements for certification carry-over from one model year to the
next are satisfied.
(iii) For a given model year, a manufacturer may elect to provide
emissions data for test engines from more engine ratings than required
by paragraph (l)(2)(ii) of this section. For each additional engine
rating tested in that given model year, the number of engine ratings
required for testing in one future model year will be reduced by one.
(iv) For the test engine, the manufacturer must use an engine aged
for a minimum of 125 hours fitted with exhaust aftertreatment emission
controls aged to be representative of useful life aging. The
manufacturer is required to submit a description of the accelerated
aging process and/or supporting data. The process and/or data must
demonstrate assurance that deterioration of the exhaust aftertreatment
emission controls is stabilized sufficiently such that it represents
emission control performance at the end of the useful life.
(3) Required testing. Except as otherwise described in this
paragraph (l)(3) of this section, the manufacturer must perform single
malfunction testing based on the applicable test with the components/
systems set at their malfunction criteria limits as determined by the
manufacturer for meeting the emissions thresholds required in
paragraphs (g) and (i) of this section and Sec. 86.010-18(h).
(i) Required testing for diesel-fueled/compression ignition
engines.
(l)(3)(i)(A) [Reserved]. For guidance see Sec. 86.010-18.
(l)(3)(i)(B) Engine misfire. The manufacturer must perform a test
at the malfunction limit established by the manufacturer for the
monitoring required by paragraph (g)(2)(ii)(B) of this section.
(l)(3)(i)(C) through (l)(3)(i)(K) [Reserved]. For guidance see
Sec. 86.010-18.
(l)(3)(ii) Required testing for gasoline-fueled/spark-ignition
engines.
(l)(3)(ii)(A) through (l)(3)(ii)(I) [Reserved]. For guidance see
Sec. 86.010-18.
(l)(3)(iii) Required testing for all engines.
(l)(3)(iii)(A) and (l)(3)(iii)(B) [Reserved]. For guidance see
Sec. 86.010-18.
(l)(3)(iv) [Reserved]. For guidance see Sec. 86.010-18.
(l)(4) Testing protocol.
(l)(4)(i) [Reserved]. For guidance see Sec. 86.010-18.
(l)(4)(ii) Test sequence.
(l)(4)(ii)(A) through (l)(4)(ii)(C) [Reserved]. For guidance see
Sec. 86.010-18.
(l)(4)(iii) A manufacturer required to test more than one test
engine according to paragraph (l)(2)(ii) of this section may use
internal calibration sign-off test procedures (e.g., forced cool downs,
less frequently calibrated emission analyzers) instead of official test
procedures to obtain the emission test data required by this paragraph
(l) of this section for all but one of the required test engines. The
manufacturer may elect this option if the data from the alternative
test procedure are representative of official emissions test results. A
manufacturer using this option is still responsible for meeting the
malfunction criteria specified in paragraphs (g) and (i) of this
section and Sec. 86.010-18(h) if and when emissions tests are
performed in accordance with official test procedures.
(l)(4)(iv) [Reserved]. For guidance see Sec. 86.010-18.
(l)(5) Evaluation protocol.
(l)(5)(i) [Reserved]. For guidance see Sec. 86.010-18.
(l)(5)(ii) If the MIL activates prior to emissions exceeding the
applicable malfunction criteria limits specified in paragraphs (g) and
(i) of this section and Sec. 86.010-18(h), no further demonstration is
required. With respect to the misfire monitor demonstration test, if
the manufacturer has elected to use the minimum misfire malfunction
criteria of one percent as allowed in paragraphs (g)(2)(ii)(B) of this
section and Sec. 86.010-18(h)(2)(ii)(B), no further demonstration is
required provided the MIL activates with engine misfire occurring at
the malfunction criteria limit.
(l)(5)(iii) through (l)(5)(iv) [Reserved]. For guidance see Sec.
86.010-18.
(l)(6) Confirmatory testing.
(i) The Administrator may perform confirmatory testing to verify
the emission test data submitted by the manufacturer as required by
paragraph (l) of this section comply with its requirements and the
malfunction criteria set forth in paragraphs (g) and (i) of this
section and Sec. 86.010-18(h). Such confirmatory testing is limited to
the test engine(s) required by paragraph (l)(2) of this section.
(l)(6)(ii) through (l)(7) [Reserved]. For guidance see Sec.
86.010-18.
(m) Certification documentation requirements.
(m)(1) through (m)(2)(iv) [Reserved]. For guidance see Sec.
86.010-18.
(m)(2)(v) Emissions test data, a description of the testing
sequence (e.g., the number and types of preconditioning cycles),
approximate time (in seconds) of MIL activation during the test,
diagnostic trouble code(s) and freeze frame information stored at the
time of detection, corresponding test results (e.g. SAE J1979 Mode/
Service $06, SAE J1939 Diagnostic Message 8 (DM8)) stored during the
test, and a description of the modified or deteriorated components used
for malfunction simulation with respect to the demonstration tests
specified in paragraph (l) of this section. The freeze frame data are
not required for engines subject to paragraph (o)(3) of this section.
(m)(2)(vi) through (m)(2)(x) [Reserved]. For guidance see Sec.
86.010-18.
(m)(2)(xi) A written identification of the communication protocol
utilized by each engine for communication with a SAE J1978/J1939 scan
tool.
(xii) A pictorial representation or written description of the
diagnostic
[[Page 3338]]
connector location including any covers or labels.
(m)(2)(xiii) [Reserved]. For guidance see Sec. 86.010-18.
(m)(2)(xiv) Build specifications provided to engine purchasers or
chassis manufacturers detailing all specifications or limitations
imposed on the engine purchaser relevant to OBD requirements or
emissions compliance (e.g., allowable MIL locations, connector location
specifications, cooling system heat rejection rates). A description of
the method or copies of agreements used to ensure engine purchasers or
chassis manufacturers will comply with the OBD and emissions relevant
build specifications (e.g., signed agreements, required audit/
evaluation procedures).
(m)(2)(xv) [Reserved]. For guidance see Sec. 86.010-18.
(n) [Reserved]. For guidance see Sec. 86.010-18.
(o) Implementation schedule. Except as provided for in paragraph
(o)(4) of this section, the requirements of this section must be met
according to the following provisions:
(1) OBD groups. The manufacturer shall define one or more OBD
groups to cover all engine ratings in all engine families. The
manufacturer must submit a grouping plan for Administrator review and
approval detailing the OBD groups and the engine families and engine
ratings within each group for a given model year.
(2) Full OBD.
(i) For all engine ratings subject to Sec. 86.010-18, the
manufacturer must implement an OBD system meeting the requirements of
this section.
(ii) On one engine rating within each of the manufacturer's OBD
groups, the manufacturer must implement an OBD system meeting the
requirements of this section. These ``full OBD'' ratings will be known
as the ``OBD parent'' ratings. The OBD parent rating for each OBD group
must be chosen as the rating having the highest weighted projected U.S.
sales within the OBD group, with U.S. sales being weighted by the
useful life of the engine rating.
(3) Extrapolated OBD. For all other engine ratings within each OBD
group, the manufacturer must implement an OBD system meeting the
requirements of this section except that the OBD system is not required
to detect a malfunction prior to exceeding the emission thresholds
shown in Table 1 of paragraph (g) of this section and Table 2 of Sec.
86.010-18(h). These extrapolated OBD engines will be known as the ``OBD
child'' ratings. On these OBD child ratings, rather than detecting a
malfunction prior to exceeding the emission thresholds, the
manufacturer must submit a plan for Administrator review and approval
that details the engineering evaluation the manufacturer will use to
establish the malfunction criteria for the OBD child ratings. The plan
must demonstrate both the use of good engineering judgment in
establishing the malfunction criteria, and robust detection of
malfunctions, including consideration of differences of base engine,
calibration, emission control components, and emission control
strategies.
(4) Engines certified as alternative fueled engines shall meet the
following requirements:
(i) To the extent feasible, those specified in paragraph (i)(3) of
this section.
(ii) Monitor the NOX aftertreatment system on engines so
equipped. A malfunction must be detected if:
(A) The NOX aftertreatment system has no detectable
amount of NOX aftertreatment capability (i.e.,
NOX catalyst conversion or NOX adsorption).
(B) The NOX aftertreatment substrate is completely
destroyed, removed, or missing.
(C) The NOX aftertreatment assembly is replaced with a
straight pipe.
(p) In-use compliance standards. For monitors required to indicate
a malfunction before emissions exceed a certain emission threshold
(e.g., 2 times any of the applicable standards):
(1) On the full OBD ratings as defined in paragraph (o)(2) of this
section, separate in-use emissions thresholds shall apply. These
thresholds are determined by doubling the applicable thresholds as
shown in Table 1 of paragraph (g) of this section and Table 2 of Sec.
86.010-18(h). The resultant thresholds apply only in-use and do not
apply for certification or selective enforcement auditing.
(2) The extrapolated OBD ratings as defined in paragraph (o)(3) of
this section shall not be evaluated against emissions levels for
purposes of OBD compliance in-use.
(3) Only the test cycle and standard determined and identified by
the manufacturer at the time of certification in accordance with Sec.
86.010-18(f) as the most stringent shall be used for the purpose of
determining OBD system noncompliance in-use.
(4) For monitors subject to meeting the minimum in-use monitor
performance ratio of 0.100 in paragraph (d)(1)(ii) of this section, the
OBD system shall not be considered noncompliant unless a representative
sample indicates the in-use ratio is below 0.050.
(5) An OBD system shall not be considered noncompliant solely due
to a failure or deterioration mode of a monitored component or system
that could not have been reasonably foreseen to occur by the
manufacturer.
13. Section 86.013-30 is added to Subpart A to read as follows:
Sec. 86.013-30 Certification.
Section 86.013-30 includes text that specifies requirements that
differ from Sec. 86.010-30. Where a paragraph in Sec. 86.010-30 is
identical and applicable to Sec. 86.013-30, this may be indicated by
specifying the corresponding paragraph and the statement ``[Reserved].
For guidance see Sec. 86.010-30.''
(a) introductory text through (f)(1)(i) [Reserved]. For guidance
see Sec. 86.010-30.
(f)(1)(ii) Diesel.
(A) If monitored for emissions performance--a reduction catalyst is
replaced with a deteriorated or defective catalyst, or an electronic
simulation of such, resulting in exhaust NOX emissions
exceeding the applicable NOX FEL+0.3 g/bhp-hr. Also if
monitored for emissions performance--an oxidation catalyst is replaced
with a deteriorated or defective catalyst, or an electronic simulation
of such, resulting in exhaust NMHC emissions exceeding 2 times the
applicable NMHC standard.
(B) If monitored for performance--a particulate trap is replaced
with a deteriorated or defective trap, or an electronic simulation of
such, resulting in either exhaust PM emissions exceeding the applicable
FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM, whichever is higher; or, exhaust
NMHC emissions exceeding 2 times the applicable NMHC standard. Also, if
monitored for performance--a particulate trap is replaced with a
catastrophically failed trap or a simulation of such.
(f)(2) [Reserved]. For guidance see Sec. 86.004-30.
(f)(3)(i) Oxygen sensors and air-fuel ratio sensors downstream of
aftertreatment devices.
(f)(3)(i)(A) [Reserved]. For guidance see Sec. 86.007-30.
(f)(3)(i)(B) Diesel. If so equipped, any oxygen sensor or air-fuel
ratio sensor located downstream of aftertreatment devices is replaced
with a deteriorated or defective sensor, or an electronic simulation of
such, resulting in exhaust emissions exceeding any of the following
levels: The applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr PM,
whichever is higher; or, the applicable NOX FEL+0.3 g/bhp-
hr; or, 2 times the applicable NMHC standard.
(ii) Oxygen sensors and air-fuel ratio sensors upstream of
aftertreatment devices.
(f)(3)(ii)(A) [Reserved]. For guidance see Sec. 86.007-30.
[[Page 3339]]
(f)(3)(ii)(B) Diesel. If so equipped, any oxygen sensor or air-fuel
ratio sensor located upstream of aftertreatment devices is replaced
with a deteriorated or defective sensor, or an electronic simulation of
such, resulting in exhaust emissions exceeding any of the following
levels: The applicable PM FEL+0.02 g/bhp-hr or 0.03 g/bhp-hr PM,
whichever is higher; or, the applicable NOX FEL+0.3 g/bhp-
hr; or, 2 times the applicable NMHC standard; or, 2 times the
applicable CO standard.
(iii) NOX sensors.
(f)(3)(iii)(A) [Reserved]. For guidance see Sec. 86.007-30.
(f)(3)(iii)(B) Diesel. If so equipped, any NOX sensor is
replaced with a deteriorated or defective sensor, or an electronic
simulation of such, resulting in exhaust emissions exceeding any of the
following levels: The applicable PM FEL+0.04 g/bhp-hr or 0.05 g/bhp-hr
PM, whichever is higher; or, the applicable NOX FEL+0.3 g/
bhp-hr.
(f)(4) [Reserved]. For guidance see Sec. 86.010-30.
(f)(5)(i) [Reserved]. For guidance see Sec. 86.007-30.
(f)(5)(ii) Diesel. A malfunction condition is induced in any
emission-related engine system or component, including but not
necessarily limited to, the exhaust gas recirculation (EGR) system, if
equipped, and the fuel control system, singularly resulting in exhaust
emissions exceeding any of the following levels: The applicable PM
FEL+0.02 g/bhp-hr or 0.03 g/bhp-hr PM, whichever is higher; or, the
applicable NOX FEL+0.3 g/bhp-hr; or, 2 times the applicable
NMHC standard; or, 2 times the applicable CO standard.
(f)(6) [Reserved]. For guidance see Sec. 86.010-30.
14. Section 86.016-18 is added to Subpart A to read as follows:
Sec. 86.016-18 On-board Diagnostics for engines used in applications
greater than 14,000 pounds GVWR.
Section 86.016-18 includes text that specifies requirements that
differ from Sec. 86.013-18. Where a paragraph in Sec. 86.013-18 is
identical and applicable to Sec. 86.016-18, this may be indicated by
specifying the corresponding paragraph and the statement ``[Reserved].
For guidance see Sec. 86.013-18.''
(a) through (n) [Reserved]. For guidance see Sec. 86.013-18.
(o) Implementation schedule. Except as provided for in paragraph
(o)(3) of this section, the requirements of this section must be met
according to the following provisions:
(1) OBD groups. The manufacturer shall define one or more OBD
groups to cover all engine ratings in all engine families. The
manufacturer must submit a grouping plan for Administrator review and
approval detailing the OBD groups and the engine families and engine
ratings within each group for a given model year.
(2) Full OBD. The manufacturer must implement an OBD system meeting
the requirements of this section on all engine ratings in all engine
families.
(3) Engines certified as alternative fueled engines shall meet the
following requirements:
(i) To the extent feasible, those specified in Sec. 86.013-
18(i)(3).
(ii) Monitor the NOX aftertreatment system on engines so
equipped. A malfunction must be detected if:
(A) The NOX aftertreatment system has no detectable
amount of NOX aftertreatment capability (i.e.,
NOX catalyst conversion or NOX adsorption).
(B) The NOX aftertreatment substrate is completely
destroyed, removed, or missing.
(C) The NOX aftertreatment assembly is replaced with a
straight pipe.
(p) In-use compliance standards. For monitors required to indicate
a malfunction before emissions exceed a certain emission threshold
(e.g., 2 times any of the applicable standards):
(1) On the engine ratings tested according to Sec. 86.013-
18(l)(2)(ii), the certification emissions thresholds shall apply in-
use.
(2) On the manufacturer's remaining engine ratings, separate in-use
emissions thresholds shall apply. These thresholds are determined by
doubling the applicable thresholds as shown in Table 1 of Sec. 86.013-
18(g) and Table 2 of Sec. 86.010-18(h). The resultant thresholds apply
only in-use and do not apply for certification or selective enforcement
auditing.
(3) An OBD system shall not be considered noncompliant solely due
to a failure or deterioration mode of a monitored component or system
that could not have been reasonably foreseen to occur by the
manufacturer.
15. Section 86.019-18 is added to subpart A to read as follows:
Sec. 86.019-18 On-board diagnostics for engines used in applications
greater than 14,000 pounds GVWR.
Section 86.019-18 includes text that specifies requirements that
differ from Sec. Sec. 86.013-18 and 86.016-18. Where a paragraph in
Sec. 86.013-18 is identical and applicable to Sec. 86.019-18, this
may be indicated by specifying the corresponding paragraph and the
statement ``[Reserved]. For guidance see Sec. 86.013-18.''
(a) through (k)(6) [Reserved]. For guidance see Sec. 86.013-18.
(k)(7) For 2019 and subsequent model year alternative-fueled
engines derived from a diesel-cycle engine, a manufacturer may meet the
standardization requirements of Sec. 86.013-18(k) that are applicable
to diesel engines rather than the requirements applicable to gasoline
engines.
(l) through (n) [Reserved]. For guidance see Sec. 86.013-18.
(o) Implementation schedule. The manufacturer must implement an OBD
system meeting the requirements of this section on all engines.
(p) In-use compliance. An OBD system shall not be considered
noncompliant solely due to a failure or deterioration mode of a
monitored component or system that could not have been reasonably
foreseen to occur by the manufacturer.
16. Section 86.1806-07 is added to Subpart S to read as follows:
Sec. 86.1806-07 On-board diagnostics for vehicles less than or equal
to 14,000 pounds GVWR.
Section 86.1806-07 includes text that specifies requirements that
differ from Sec. 86.1806-05. Where a paragraph in Sec. 86.1806-05 is
identical and applicable to Sec. 86.1806-07, this may be indicated by
specifying the corresponding paragraph and the statement ``[Reserved].
For guidance see Sec. 86.1806-05.''
(a) through (a)(2) [Reserved]. For guidance see Sec. 86.1806-05.
(a)(3) An OBD system demonstrated to fully meet the requirements in
Sec. 86.007-17 may be used to meet the requirements of this section,
provided that such an OBD system also incorporates appropriate
transmission diagnostics as may be required under this section, and
provided that the Administrator finds that a manufacturer's decision to
use the flexibility in this paragraph (a)(3) is based on good
engineering judgement.
(b) through (h) [Reserved]. For guidance see Sec. 86.1806-05.
(i) Deficiencies and alternative fueled vehicles. Upon application
by the manufacturer, the Administrator may accept an OBD system as
compliant even though specific requirements are not fully met. Such
compliances without meeting specific requirements, or deficiencies,
will be granted only if compliance would be infeasible or unreasonable
considering such factors as, but not limited to: technical feasibility
of the given monitor and lead time and production cycles including
phase-in or phase-out of vehicle designs and programmed upgrades of
computers. Unmet requirements should
[[Page 3340]]
not be carried over from the previous model year except where
unreasonable hardware or software modifications would be necessary to
correct the deficiency, and the manufacturer has demonstrated an
acceptable level of effort toward compliance as determined by the
Administrator. Furthermore, EPA will not accept any deficiency requests
that include the complete lack of a major diagnostic monitor (``major''
diagnostic monitors being those for exhaust aftertreatment devices,
oxygen sensor, air-fuel ratio sensor, NOX sensor, engine
misfire, evaporative leaks, and diesel EGR, if equipped), with the
possible exception of the special provisions for alternative fueled
engines. For alternative fueled vehicles (e.g., natural gas, liquefied
petroleum gas, methanol, ethanol), manufacturers may request the
Administrator to waive specific monitoring requirements of this section
for which monitoring may not be reliable with respect to the use of the
alternative fuel. At a minimum, alternative fuel engines must be
equipped with an OBD system meeting OBD requirements to the extent
feasible as approved by the Administrator.
(j) California OBDII compliance option. For light-duty vehicles,
light-duty trucks, and heavy-duty vehicles weighing 14,000 pounds GVWR
or less, demonstration of compliance with California OBD II
requirements (Title 13 California Code of Regulations Sec. 1968.2 (13
CCR 1968.2)), as modified and released on August 11, 2006, shall
satisfy the requirements of this section, except that compliance with
13 CCR 1968.2(e)(4.2.2)(C), pertaining to 0.02-inch evaporative leak
detection, and 13 CCR 1968.2(d)(1.4), pertaining to tampering
protection, are not required to satisfy the requirements of this
section. Also, the deficiency provisions of 13 CCR 1968.2(k) do not
apply. The deficiency provisions of paragraph (i) of this section and
the evaporative leak detection requirement of Sec. 86.1806-05(b)(4)
apply to manufacturers selecting this paragraph for demonstrating
compliance. In addition, demonstration of compliance with 13 CCR
1968.2(e)(15.2.1)(C), to the extent it applies to the verification of
proper alignment between the camshaft and crankshaft, applies only to
vehicles equipped with variable valve timing.
(k) through (m) [Reserved]. For guidance see Sec. 86.1806-05.
(n) For diesel complete heavy-duty vehicles, in lieu of the
malfunction descriptions of Sec. 86.1806-05(b), the malfunction
descriptions of this paragraph (n) shall apply. The OBD system must
detect and identify malfunctions in all monitored emission-related
powertrain systems or components according to the following malfunction
definitions as measured and calculated in accordance with test
procedures set forth in subpart B of this part (chassis-based test
procedures), excluding those test procedures defined as
``Supplemental'' test procedures in Sec. 86.004-2 and codified in
Sec. Sec. 86.158, 86.159, and 86.160.
(1) Catalysts and particulate traps.
(i) If equipped, catalyst deterioration or malfunction before it
results in exhaust emissions exceeding 3 times the applicable
NOX standard. This requirement applies only to reduction
catalysts; monitoring of oxidation catalysts is not required. This
monitoring need not be done if the manufacturer can demonstrate that
deterioration or malfunction of the system will not result in
exceedance of the threshold.
(ii) If equipped with a particulate trap, catastrophic failure of
the device must be detected. Any particulate trap whose complete
failure results in exhaust emissions exceeding 1.5 times the applicable
standard or FEL for NOX or PM must be monitored for such
catastrophic failure. This monitoring need not be done if the
manufacturer can demonstrate that a catastrophic failure of the system
will not result in exceedance of the threshold.
(2) Engine misfire. Lack of cylinder combustion must be detected.
(3)(i) Oxygen sensors and air-fuel ratio sensors downstream of
aftertreatment devices. If equipped, sensor deterioration or
malfunction resulting in exhaust emissions exceeding any of the
following levels: 4 times the applicable PM standard; or, 3 times the
applicable NOX standard; or, 2.5 times the applicable NMHC
standard.
(ii) Oxygen sensors and air-fuel ratio sensors upstream of
aftertreatment devices. If equipped, sensor deterioration or
malfunction resulting in exhaust emissions exceeding any of the
following levels: 4 times the applicable PM standard; or, 3 times the
applicable NOX standard; or, 2.5 times the applicable NMHC
standard; or, 2.5 times the applicable CO standard.
(iii) NOX sensors. If equipped, sensor deterioration or
malfunction resulting in exhaust emissions exceeding any of the
following levels: 5 times the applicable PM standard; or, 4 times the
applicable NOX standard.
(4) [Reserved.]
(5) Other emission control systems and components. Any
deterioration or malfunction occurring in an engine system or component
directly intended to control emissions, including but not necessarily
limited to, the exhaust gas recirculation (EGR) system, if equipped,
and the fuel control system, singularly resulting in exhaust emissions
exceeding any of the following levels: 4 times the applicable PM
standard; or, 3 times the applicable NOX standard; or, 2.5
times the applicable NMHC standard; or, 2.5 times the applicable CO
standard. A functional check, as described in paragraph (n)(6) of this
section, may satisfy the requirements of this paragraph (n)(5) provided
the manufacturer can demonstrate that a malfunction would not cause
emissions to exceed the applicable levels. This demonstration is
subject to Administrator approval. For engines equipped with crankcase
ventilation (CV), monitoring of the CV system is not necessary provided
the manufacturer can demonstrate to the Administrator's satisfaction
that the CV system is unlikely to fail.
(6) Other emission-related powertrain components. Any other
deterioration or malfunction occurring in an electronic emission-
related powertrain system or component not otherwise described in
paragraphs (n)(1) through (n)(5) of this section that either provides
input to or receives commands from the on-board computer and has a
measurable impact on emissions; monitoring of components required by
this paragraph (n)(6) must be satisfied by employing electrical circuit
continuity checks and rationality checks for computer input components
(input values within manufacturer specified ranges based on other
available operating parameters), and functionality checks for computer
output components (proper functional response to computer commands)
except that the Administrator may waive such a rationality or
functionality check where the manufacturer has demonstrated
infeasibility. Malfunctions are defined as a failure of the system or
component to meet the electrical circuit continuity checks or the
rationality or functionality checks.
(7) Performance of OBD functions. Any sensor or other component
deterioration or malfunction which renders that sensor or component
incapable of performing its function as part of the OBD system must be
detected and identified on engines so equipped.
(o) For diesel complete heavy-duty vehicles, in lieu of the
certification provisions of Sec. 86.1806-05(k), the certificate
provisions of this paragraph (o) shall apply. For test groups required
to have an OBD system, certification will not be granted if, for any
test vehicle approved by the Administrator in consultation with the
manufacturer, the malfunction indicator light does not
[[Page 3341]]
illuminate under any of the following circumstances, unless the
manufacturer can demonstrate that any identified OBD problems
discovered during the Administrator's evaluation will be corrected on
production vehicles.
(1)(i) If monitored for emissions performance--a catalyst is
replaced with a deteriorated or defective catalyst, or an electronic
simulation of such, resulting in exhaust emissions exceeding 3 times
the applicable NOX standard. This requirement applies only
to reduction catalysts.
(ii) If monitored for performance--a particulate trap is replaced
with a trap that has catastrophically failed, or an electronic
simulation of such.
(2) An engine misfire condition is induced and is not detected.
(3)(i) If so equipped, any oxygen sensor or air-fuel ratio sensor
located downstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels: 4
times the applicable PM standard; or, 3 times the applicable
NOX standard; or, 2.5 times the applicable NMHC standard.
(ii) If so equipped, any oxygen sensor or air-fuel ratio sensor
located upstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels: 4
times the applicable PM standard; or, 3 times the applicable
NOX standard; or, 2.5 times the applicable NMHC standard;
or, 2.5 times the applicable CO standard.
(iii) If so equipped, any NOX sensor is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels: 5
times the applicable PM standard; or, 4 times the applicable
NOX standard.
(4) [Reserved.]
(5) A malfunction condition is induced in any emission-related
engine system or component, including but not necessarily limited to,
the exhaust gas recirculation (EGR) system, if equipped, and the fuel
control system, singularly resulting in exhaust emissions exceeding any
of the following levels: 4 times the applicable PM standard; or, 3
times the applicable NOX standard; or, 2.5 times the
applicable NMHC standard; or, 2.5 times the applicable CO standard.
(6) A malfunction condition is induced in an electronic emission-
related powertrain system or component not otherwise described in this
paragraph (o) that either provides input to or receives commands from
the on-board computer resulting in a measurable impact on emissions.
17. Section 86.1806-10 is added to Subpart S to read as follows:
Sec. 86.1806-10 On-board diagnostics for vehicles less than or equal
to 14,000 pounds GVWR.
Section 86.1806-10 includes text that specifies requirements that
differ from Sec. 86.1806-05 and Sec. 86.1806-07. Where a paragraph in
Sec. 86.1806-05 or Sec. 86.1806-07 is identical and applicable to
Sec. 86.1806-10, this may be indicated by specifying the corresponding
paragraph and the statement ``[Reserved]. For guidance see Sec.
86.1806-05.'' or ``[Reserved]. For guidance see Sec. 86.1806-07.''
(a) General.
(1) All light-duty vehicles, light-duty trucks and complete heavy-
duty vehicles weighing 14,000 pounds GVWR or less (including MDPVs)
must be equipped with an onboard diagnostic (OBD) system capable of
monitoring all emission-related powertrain systems or components during
the applicable useful life of the vehicle. All systems and components
required to be monitored by these regulations must be evaluated
periodically, but no less frequently than once per applicable
certification test cycle as defined in paragraphs (a) and (d) of
Appendix I of this part, or similar trip as approved by the
Administrator.
(2) [Reserved.]
(3) An OBD system demonstrated to fully meet the requirements in
Sec. 86.010-17 may be used to meet the requirements of this section,
provided that such an OBD system also incorporates appropriate
transmission diagnostics as may be required under this section, and
provided that the Administrator finds that a manufacturer's decision to
use the flexibility in this paragraph (a)(3) is based on good
engineering judgement.
(b) through (m) [Reserved]. For guidance see Sec. 86.1806-07.
(n) For diesel complete heavy-duty vehicles, in lieu of the
malfunction descriptions of Sec. 86.1806-05(b), the malfunction
descriptions of this paragraph (n) shall apply. The OBD system must
detect and identify malfunctions in all monitored emission-related
powertrain systems or components according to the following malfunction
definitions as measured and calculated in accordance with test
procedures set forth in subpart B of this part (chassis-based test
procedures), excluding those test procedures defined as
``Supplemental'' test procedures in Sec. 86.004-2 and codified in
Sec. Sec. 86.158, 86.159, and 86.160.
(1) Catalysts and particulate traps.
(i) If equipped, reduction catalyst deterioration or malfunction
before it results in exhaust NOX emissions exceeding the
applicable NOX standard+0.3 g/mi. If equipped, oxidation
catalyst deterioration or malfunction before it results in exhaust NMHC
emissions exceeding 2.5 times the applicable NMHC standard. These
catalyst monitoring requirements need not be done if the manufacturer
can demonstrate that deterioration or malfunction of the system will
not result in exceedance of the threshold.
(ii) If equipped, diesel particulate trap deterioration or
malfunction before it results in exhaust emissions exceeding any of the
following levels: 4 times the applicable PM standard; or, exhaust NMHC
emissions exceeding 2.5 times the applicable NMHC standard.
Catastrophic failure of the particulate trap must also be detected. In
addition, the absence of the particulate trap or the trapping substrate
must be detected.
(2) Engine misfire. Lack of cylinder combustion must be detected.
(3)(i) Oxygen sensors and air-fuel ratio sensors downstream of
aftertreatment devices. If equipped, sensor deterioration or
malfunction resulting in exhaust emissions exceeding any of the
following levels: 4 times the applicable PM standard; or, the
applicable NOX standard+0.3 g/mi; or, 2.5 times the
applicable NMHC standard.
(ii) Oxygen sensors and air-fuel ratio sensors upstream of
aftertreatment devices. If equipped, sensor deterioration or
malfunction resulting in exhaust emissions exceeding any of the
following levels: The applicable PM standard+0.02 g/mi; or, the
applicable NOX standard+0.3 g/mi; or, 2.5 times the
applicable NMHC standard; or, 2.5 times the applicable CO standard.
(iii) NOX sensors. If equipped, sensor deterioration or
malfunction resulting in exhaust emissions exceeding any of the
following levels: 4 times the applicable PM standard; or, the
applicable NOX standard+0.3 g/mi.
(4) [Reserved.]
(5) Other emission control systems and components. Any
deterioration or malfunction occurring in an engine system or component
directly intended to control emissions, including but not necessarily
limited to, the exhaust gas recirculation (EGR) system, if equipped,
and the fuel control system, singularly resulting in exhaust emissions
exceeding any of the following levels: 4 times the applicable PM
standard; or, the applicable NOX standard+0.3 g/mi;
[[Page 3342]]
or, 2.5 times the applicable NMHC standard; or, 2.5 times the
applicable CO standard. A functional check, as described in paragraph
(n)(6) of this section, may satisfy the requirements of this paragraph
(n)(5) provided the manufacturer can demonstrate that a malfunction
would not cause emissions to exceed the applicable levels. This
demonstration is subject to Administrator approval. For engines
equipped with crankcase ventilation (CV), monitoring of the CV system
is not necessary provided the manufacturer can demonstrate to the
Administrator's satisfaction that the CV system is unlikely to fail.
(6) Other emission-related powertrain components. Any other
deterioration or malfunction occurring in an electronic emission-
related powertrain system or component not otherwise described in
paragraphs (n)(1) through (n)(5) of this section that either provides
input to or receives commands from the on-board computer and has a
measurable impact on emissions; monitoring of components required by
this paragraph (n)(6) must be satisfied by employing electrical circuit
continuity checks and rationality checks for computer input components
(input values within manufacturer specified ranges based on other
available operating parameters), and functionality checks for computer
output components (proper functional response to computer commands)
except that the Administrator may waive such a rationality or
functionality check where the manufacturer has demonstrated
infeasibility. Malfunctions are defined as a failure of the system or
component to meet the electrical circuit continuity checks or the
rationality or functionality checks.
(7) Performance of OBD functions. Any sensor or other component
deterioration or malfunction which renders that sensor or component
incapable of performing its function as part of the OBD system must be
detected and identified on engines so equipped.
(o) For diesel complete heavy-duty vehicles, in lieu of the
certification provisions of Sec. 86.1806-5(k), the certification
provisions of this paragraph (o) shall apply. For test groups required
to have an OBD system, certification will not be granted if, for any
test vehicle approved by the Administrator in consultation with the
manufacturer, the malfunction indicator light does not illuminate under
any of the following circumstances, unless the manufacturer can
demonstrate that any identified OBD problems discovered during the
Administrator's evaluation will be corrected on production vehicles.
(1)(i) If monitored for emissions performance--a reduction catalyst
is replaced with a deteriorated or defective catalyst, or an electronic
simulation of such, resulting in exhaust NOX emissions
exceeding the applicable NOX standard+0.3 g/mi. Also if
monitored for emissions performance--an oxidation catalyst is replaced
with a deteriorated or defective catalyst, or an electronic simulation
of such, resulting in exhaust NMHC emissions exceeding 2.5 times the
applicable NMHC standard.
(ii) If monitored for performance--a particulate trap is replaced
with a deteriorated or defective trap, or an electronic simulation of
such, resulting in exhaust PM emissions exceeding 4 times the
applicable PM standard or exhaust NMHC emissions exceeding 2.5 times
the applicable NMHC standard. Also, if monitored for performance--a
particulate trap is replaced with a catastrophically failed trap or a
simulation of such.
(2) An engine misfire condition is induced and is not detected.
(3)(i) If so equipped, any oxygen sensor or air-fuel ratio sensor
located downstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels: 4
times the applicable PM standard; or, the applicable NOX
standard+0.3 g/mi; or, 2.5 times the applicable NMHC standard.
(ii) If so equipped, any oxygen sensor or air-fuel ratio sensor
located upstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels:
The applicable PM standard+0.02 g/mi; or, the applicable NOX
standard+0.3 g/mi; or, 2.5 times the applicable NMHC standard; or, 2.5
times the applicable CO standard.
(iii) If so equipped, any NOX sensor is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels: 4
times the applicable PM standard; or, the applicable NOX
standard+0.3 g/mi.
(4) [Reserved.]
(5) A malfunction condition is induced in any emission-related
engine system or component, including but not necessarily limited to,
the exhaust gas recirculation (EGR) system, if equipped, and the fuel
control system, singularly resulting in exhaust emissions exceeding any
of the following levels: 4 times the applicable PM standard; or, the
applicable NOX standard+0.3 g/mi; or, 2.5 times the
applicable NMHC standard; or, 2.5 times the applicable CO standard.
(6) A malfunction condition is induced in an electronic emission-
related powertrain system or component not otherwise described in this
paragraph (o) that either provides input to or receives commands from
the on-board computer resulting in a measurable impact on emissions.
18. Section 86.1806-13 is added to Subpart S to read as follows:
Sec. 86.1806-13 On-board diagnostics for vehicles less than or equal
to 14,000 pounds GVWR.
Section 86.1806-13 includes text that specifies requirements that
differ from Sec. 86.1806-05, Sec. 86.1806-07 and Sec. 86.1806-10.
Where a paragraph in Sec. 86.1806-05 or Sec. 86.1806-07 or Sec.
86.1806-10 is identical and applicable to Sec. 86.1806-13 this may be
indicated by specifying the corresponding paragraph and the statement
``[Reserved]. For guidance see Sec. 86.1806-05.'' or ``[Reserved]. For
guidance see Sec. 86.1806-07.'' or ``[Reserved]. For guidance see
Sec. 86.1806-10.''
(a)(1) [Reserved]. For guidance see Sec. 86.1806-10.
(a)(2) [Reserved.]
(3) An OBD system demonstrated to fully meet the requirements in
Sec. 86.013-17 may be used to meet the requirements of this section,
provided that such an OBD system also incorporates appropriate
transmission diagnostics as may be required under this section, and
provided that the Administrator finds that a manufacturer's decision to
use the flexibility in this paragraph (a)(3) is based on good
engineering judgement.
(b) through (m) [Reserved]. For guidance see Sec. 86.1806-07.
(n) For diesel complete heavy-duty vehicles, in lieu of the
malfunction descriptions of Sec. 86.1806-05(b), the malfunction
descriptions of this paragraph (n) shall apply. The OBD system must
detect and identify malfunctions in all monitored emission-related
powertrain systems or components according to the following malfunction
definitions as measured and calculated in accordance with test
procedures set forth in subpart B of this part (chassis-based test
procedures), excluding those test procedures defined as
``Supplemental'' test procedures in Sec. 86.004-2 and codified in
Sec. Sec. 86.158, 86.159, and 86.160.
(1) Catalysts and particulate traps.
(i) If equipped, reduction catalyst deterioration or malfunction
before it results in exhaust NOX emissions exceeding the
applicable NOX
[[Page 3343]]
standard+0.3 g/mi. If equipped, oxidation catalyst deterioration or
malfunction before it results in exhaust NMHC emissions exceeding 2
times the applicable NMHC standard. These catalyst monitoring
requirements need not be done if the manufacturer can demonstrate that
deterioration or malfunction of the system will not result in
exceedance of the threshold.
(ii) If equipped, diesel particulate trap deterioration or
malfunction before it results in exhaust emissions exceeding any of the
following levels: the applicable PM standard+0.04 g/mi; or, exhaust
NMHC emissions exceeding 2 times the applicable NMHC standard.
Catastrophic failure of the particulate trap must also be detected. In
addition, the absence of the particulate trap or the trapping substrate
must be detected.
(2) Engine misfire. Lack of cylinder combustion must be detected.
(3)(i) Oxygen sensors and air-fuel ratio sensors downstream of
aftertreatment devices. If equipped, sensor deterioration or
malfunction resulting in exhaust emissions exceeding any of the
following levels: the applicable PM standard+0.04 g/mi; or, the
applicable NOX standard+0.3 g/mi; or, 2 times the applicable
NMHC standard.
(ii) Oxygen sensors and air-fuel ratio sensors upstream of
aftertreatment devices. If equipped, sensor deterioration or
malfunction resulting in exhaust emissions exceeding any of the
following levels: the applicable PM standard+0.02 g/mi; or, the
applicable NOX standard+0.3 g/mi; or, 2 times the applicable
NMHC standard; or, 2 times the applicable CO standard.
(iii) NOX sensors. If equipped, sensor deterioration or
malfunction resulting in exhaust emissions exceeding any of the
following levels: the applicable PM standard+0.04 g/mi; or, the
applicable NOX standard+0.3 g/mi.
(4) [Reserved.]
(5) Other emission control systems and components. Any
deterioration or malfunction occurring in an engine system or component
directly intended to control emissions, including but not necessarily
limited to, the exhaust gas recirculation (EGR) system, if equipped,
and the fuel control system, singularly resulting in exhaust emissions
exceeding any of the following levels: the applicable PM standard+0.02
g/mi; or, the applicable NOX standard+0.3 g/mi; or, 2 times
the applicable NMHC standard; or, 2 times the applicable CO standard. A
functional check, as described in paragraph (n)(6) of this section, may
satisfy the requirements of this paragraph (n)(5) provided the
manufacturer can demonstrate that a malfunction would not cause
emissions to exceed the applicable levels. This demonstration is
subject to Administrator approval. For engines equipped with crankcase
ventilation (CV), monitoring of the CV system is not necessary provided
the manufacturer can demonstrate to the Administrator's satisfaction
that the CV system is unlikely to fail.
(6) Other emission-related powertrain components. Any other
deterioration or malfunction occurring in an electronic emission-
related powertrain system or component not otherwise described in
paragraphs (n)(1) through (n)(5) of this section that either provides
input to or receives commands from the on-board computer and has a
measurable impact on emissions; monitoring of components required by
this paragraph (n)(6) must be satisfied by employing electrical circuit
continuity checks and rationality checks for computer input components
(input values within manufacturer specified ranges based on other
available operating parameters), and functionality checks for computer
output components (proper functional response to computer commands)
except that the Administrator may waive such a rationality or
functionality check where the manufacturer has demonstrated
infeasibility. Malfunctions are defined as a failure of the system or
component to meet the electrical circuit continuity checks or the
rationality or functionality checks.
(7) Performance of OBD functions. Any sensor or other component
deterioration or malfunction which renders that sensor or component
incapable of performing its function as part of the OBD system must be
detected and identified on engines so equipped.
(o) For diesel complete heavy-duty vehicles, in lieu of the
certification provisions of paragraph (k) of this section, the
certification provisions of this paragraph (o) shall apply. For test
groups required to have an OBD system, certification will not be
granted if, for any test vehicle approved by the Administrator in
consultation with the manufacturer, the malfunction indicator light
does not illuminate under any of the following circumstances, unless
the manufacturer can demonstrate that any identified OBD problems
discovered during the Administrator's evaluation will be corrected on
production vehicles.
(1)(i) If monitored for emissions performance--a reduction catalyst
is replaced with a deteriorated or defective catalyst, or an electronic
simulation of such, resulting in exhaust NOX emissions
exceeding the applicable NOX standard+0.3 g/mi. Also if
monitored for emissions performance--an oxidation catalyst is replaced
with a deteriorated or defective catalyst, or an electronic simulation
of such, resulting in exhaust NMHC emissions exceeding 2 times the
applicable NMHC standard.
(ii) If monitored for performance--a particulate trap is replaced
with a deteriorated or defective trap, or an electronic simulation of
such, resulting in exhaust PM emissions exceeding the applicable
standard+0.04 g/mi or exhaust NMHC emissions exceeding 2 times the
applicable NMHC standard. Also, if monitored for performance--a
particulate trap is replaced with a catastrophically failed trap or a
simulation of such.
(2) An engine misfire condition is induced and is not detected.
(3)(i) If so equipped, any oxygen sensor or air-fuel ratio sensor
located downstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM standard+0.04 g/mi; or, the applicable NOX
standard+0.3 g/mi; or, 2 times the applicable NMHC standard.
(ii) If so equipped, any oxygen sensor or air-fuel ratio sensor
located upstream of aftertreatment devices is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM standard+0.02 g/mi; or, the applicable NOX
standard+0.3 g/mi; or, 2 times the applicable NMHC standard; or, 2
times the applicable CO standard.
(iii) If so equipped, any NOX sensor is replaced with a
deteriorated or defective sensor, or an electronic simulation of such,
resulting in exhaust emissions exceeding any of the following levels:
the applicable PM standard+0.04 g/mi; or, the applicable NOX
standard+0.3 g/mi.
(4) [Reserved.]
(5) A malfunction condition is induced in any emission-related
engine system or component, including but not necessarily limited to,
the exhaust gas recirculation (EGR) system, if equipped, and the fuel
control system, singularly resulting in exhaust emissions exceeding any
of the following levels: the applicable PM standard+0.02 g/mi; or, the
applicable NOX standard+0.3 g/mi; or, 2 times the applicable
NMHC standard; or, 2 times the applicable CO standard.
(6) A malfunction condition is induced in an electronic emission-
related powertrain system or component not otherwise described in this
[[Page 3344]]
paragraph (o) that either provides input to or receives commands from
the on-board computer resulting in a measurable impact on emissions.
[FR Doc. 07-110 Filed 1-23-07; 8:45 am]
BILLING CODE 6560-50-P