The Y platform , or Y body , designation has been used twice by the General Motors Corporation to describe a series of vehicles all built on the same basic body and sharing many parts and characteristics. The first was for a group of entry-level compacts including the conventional front-engine compacts built by GM divisions Buick , Oldsmobile and Pontiac from 1961 to 1963. The second, and current, incarnation is used for a high-end rear-wheel drive sports-car platform (chiefly that of the Chevrolet Corvette ) from the 1970s through the 2000s.
85-479: On-board diagnostics ( OBD ) is a term referring to a vehicle's self-diagnostic and reporting capability. In the United States, this capability is a requirement to comply with federal emissions standards to detect failures that may increase the vehicle tailpipe emissions to more than 150% of the standard to which it was originally certified. OBD systems give the vehicle owner or repair technician access to
170-606: A de facto standard for vehicle manufacturers to follow. Vehicle emission standards have generally been points of debate between the government, vehicle manufacturers, and environmental groups, and has become a point of political debate. The Clean Air Act of 1963 (CAA) was passed as an extension of the Air Pollution Control Act of 1955, encouraging the federal government via the United States Public Health Service under
255-512: A gross vehicular weight rating (GVWR) below 8,500 pounds (3,856 kg) and are divided into five categories: one for passenger cars, and four for light-duty trucks (which include SUVs and minivans ) divided up based on the vehicle weight and cargo capacity. California's Low-emission vehicle (LEV) program defines six automotive emission standards which are stricter than the United States' national Tier regulations. Each standard has several targets depending on vehicle weight and cargo capacity;
340-528: A 0 if complies to the EOBD standard. So it should look like P0xxx. The next character would refer to the sub system. The following two characters would refer to the individual fault within each subsystem. The term "EOBD2" is marketing speak used by some vehicle manufacturers to refer to manufacturer-specific features that are not actually part of the OBD or EOBD standard. In this case "E" stands for Enhanced. JOBD
425-544: A 160 baud rate, while later versions went up to 8192 baud and used bi-directional communications to the PCM. The regulatory intent of OBD-I was to encourage auto manufacturers to design reliable emission control systems that remain effective for the vehicle's "useful life". The hope was that by forcing annual emissions testing for California starting in 1988, and denying registration to vehicles that did not pass, drivers would tend to purchase vehicles that would more reliably pass
510-441: A GVWR of 10,000 pounds (4,500 kg) or less was projected to average 35.5 miles per gallon (mpg) for the 2016 model year based on the newly-established targets and projected fleet mix. The average for its cars will have to be 42 mpg, and for its trucks will be 26 mpg by 2016, in coordination with new CAFE standards . If the average fuel economy of a manufacturer's annual fleet of vehicle production falls below its defined standard,
595-866: A combination of legislative mandates enacted by Congress through Clean Air Act (CAA) amendments from 1970 onwards, and executive regulations managed nationally by the Environmental Protection Agency (EPA), and more recently along with the National Highway Traffic Safety Administration (NHTSA). These standards cover tailpipe pollution , including carbon monoxide , nitrogen oxides , and particulate emissions , and newer versions have incorporated fuel economy standards. However they lag behind European emission standards , which limit air pollution from brakes and tires . In nearly all cases, these agencies set standards that are expected to be met on
680-506: A different amount of carbon per gallon or liter. The ratings reflect carbon dioxide (CO 2 ), nitrous oxide (N 2 O) and methane (CH 4 ) emissions, weighted to reflect each gas's relative contribution to the greenhouse effect . Under Section 209 of the Clean Air Act (CAA), California is given the ability to apply for special waivers to apply its own emission standards for new motor vehicles that are at least as stringent as
765-582: A fleet-wide basis from automobile and other vehicle manufacturers, with states delegated to enforce those standards but not allowed to set stricter requirements. California has generally been the exception, having been granted a waiver and given allowance to set stricter standards as it had established its own via the California Air Resources Board prior to the 1970 CAA amendments. Several other states have since also received waivers to follow California's standards, which have also become
850-551: A list of generic OBD-II DTCs suggested by the SAE, see Table of OBD-II Codes . Individual manufacturers often enhance the OBD-II code set with additional proprietary DTCs. Here is a basic introduction to the OBD communication protocol according to ISO 15031. In SAE J1979 these "modes" were renamed to "services", starting in 2003. United States vehicle emission standards United States vehicle emission standards are set through
935-466: A new national fuel economy and emissions policy that incorporated California's contested plan to curb greenhouse gas emissions on its own, apart from federal government regulations. The standards are formatted such that each vehicle has an emissions target as a function of the product of its wheelbase and average track width with separate functions for passenger cars and light trucks with progressively smaller targets by model year. Thus each manufacturer has
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#17327881040841020-410: A partial implementation of OBD-II which General Motors used on some vehicles in 1994, 1995, & 1996. (GM did not use the term OBD 1.5 in the documentation for these vehicles — they simply have an OBD and an OBD-II section in the service manual.) For example, the 1994–1995 model year Corvettes have one post-catalyst oxygen sensor (although they have two catalytic converters ), and have a subset of
1105-667: A patchwork of regulations across the United States. The automobile industry lobbied to Congress, and the CAA was modified in 1967 with the National Emissions Standards Act (also known as the Air Quality Act) that expressly prevented states from setting more restrictive emission standards than the federal levels. However, because California has already established its program, it was granted a waiver and allowed to keep its standards. This Act did give states
1190-565: A requirement in 2014; gasoline vehicles were exempt. The phase-in of new tailpipe and evaporative emission standards begin to phase-in beginning with the 2017 model year along with new fuel standards. New standards were set in March 2024 to be phased in beginning with the 2027 model year. Heavy-duty vehicles must comply with more stringent exhaust emission standards and requires ultra-low sulfur diesel (ULSD) fuel (15 ppm maximum) beginning in 2007 model year. Federal emissions regulations cover
1275-1446: A scan tool whether the ignition is on. VW: Switched +12 to tell a scan tool whether the ignition is on. Mercedes (K-Line): Ignition control (EZS), air-conditioner (KLA), PTS, safety systems (Airbag, SRS, AB) and some other. GM: 8192 baud ALDL where fitted. BMW: RPM signal. Toyota: RPM signal. Mercedes (K-Line): ABS, ASR, ESP, ETS, BAS diagnostic. SAE J1850 PWM and VPW SAE J1850 PWM only (not SAE 1850 VPW) Ethernet TX+ (Diagnostics over IP) Ford DCL(+) Argentina, Brazil (pre OBD-II) 1997–2000, USA, Europe, etc. Chrysler CCD Bus(+) Mercedes (TNA): TD engine rotation speed. Ethernet TX- (Diagnostics over IP) Ford DCL(-) Argentina, Brazil (pre OBD-II) 1997–2000, USA, Europe, etc. Chrysler CCD Bus(-) Mercedes (K-Line): Gearbox and other transmission components (EGS, ETC, FTC). Ethernet RX+ (Diagnostics over IP) Mercedes (K-Line): All activity module (AAM), Radio (RD), ICS (and more) Ethernet RX- (Diagnostics over IP) Ford: FEPS – Programming PCM voltage Mercedes (K-Line): AB diagnostic – safety systems. (ISO 15765-4 and SAE J2284) (ISO 15765-4 and SAE J2284) (ISO 9141-2 and ISO 14230-4) (ISO 9141-2 and ISO 14230-4) Activate Ethernet (Diagnostics over IP) Many BMWs: A second K-line for non OBD-II (Body/Chassis/Infotainment) systems. Mercedes: Ignition (+12 Volt for type A connector) (+24 Volt for type B connector) The assignment of unspecified pins
1360-558: A typical driving pattern. The FTP-75 city driving test (averaging about 21 miles per hour (34 km/h)) and the HWFET highway driving test (averaging about 48 miles per hour (77 km/h)) are used for measuring both emissions and fuel economy. Two sets, or tiers, of emission standards for light-duty vehicles in the United States were defined as a result of the Clean Air Act Amendments of 1990. The Tier I standard
1445-441: A unique standard for each model year based on the characteristics of vehicles it actually produces. The new standards established a credit trading system whereby manufacturers that overperform their annual target may sell credits to other manufacturers which they then may use to meet a credit shortfall it has from failing to meet its standards through emissions improvements. The combined fleet fuel economy for new cars and trucks with
1530-692: Is a version of OBD-II for vehicles sold in Japan. The ADR 79/01 (Vehicle Standard ( A ustralian D esign R ule 79/01 – Emission Control for Light Vehicles) 2005) standard is the Australian equivalent of OBD-II. It applies to all vehicles of category M1 and N1 with a Gross Vehicle Weight rating of 3,500 kg (7,700 lb) or less, registered from new within Australia and produced since January 1, 2006 for petrol -engined cars and since January 1, 2007 for diesel -engined cars. For newly introduced models,
1615-494: Is essentially the same as OBD-II, with the same SAE J1962 diagnostic link connector and signal protocols being used. In North America, EMD and EMD+ are on-board diagnostic systems that were used on vehicles with a gross vehicle weight rating of 14,000 lb (6,400 kg) or more between the 2007 and 2012 model years if those vehicles did not already implement OBD-II. EMD was used on California emissions vehicles between model years 2007 and 2009 that did not already have OBD-II. EMD
1700-579: Is left to the vehicle manufacturer's discretion. The European on-board diagnostics (EOBD) regulations are the European equivalent of OBD-II, and apply to all passenger cars of category M1 (with no more than 8 passenger seats and a Gross Vehicle Weight rating of 2,500 kg, 5,500 lb or less) first registered within EU member states since January 1, 2001 for petrol -engined cars and since January 1, 2004 for diesel engined cars. For newly introduced models,
1785-570: Is the data stream, pins 4 and 5 are ground, and pin 16 is the battery voltage. An OBD 1.5 compatible scan tool is required to read codes generated by OBD 1.5. Additional vehicle-specific diagnostic and control circuits are also available on this connector. For instance, on the Corvette there are interfaces for the Class 2 serial data stream from the PCM, the CCM diagnostic terminal, the radio data stream,
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#17327881040841870-730: Is timed to coordinate with the Tier 2 rollout. The PZEV and AT-PZEV ratings are for vehicles which achieve a SULEV II rating and also have systems to eliminate evaporative emissions from the fuel system and which have 150,000-mile/15-year warranties on emission-control components. Several ordinary gasoline vehicles from the 2001 and later model years qualify as PZEVs. If a PZEV has technology that can also be used in ZEVs like an electric motor or high-pressure gaseous fuel tanks for compressed natural gas (CNG) or liquified petroleum gas (LPG), it qualifies as an AT-PZEV. Diesel particulate filters became
1955-531: Is used for 12-volt vehicles and type B for 24-volt vehicles. Unlike the OBD-I connector, which was sometimes found under the bonnet of the vehicle, the OBD-II connector is required to be within 2 feet (0.61 m) of the steering wheel (unless an exemption is applied for by the manufacturer, in which case it is still somewhere within reach of the driver). SAE J1962 defines the pinout of the connector as: GM: J2411 GMLAN/SWC/Single-Wire CAN. Audi: Switched +12 to tell
2040-574: The Alliance of Automobile Manufacturers had sued the state of Vermont to block rules calling for a 30 percent reduction in GHG emissions by 2016. Members of the auto industry argued that complying with these regulations would require major technological advances and raise the prices of vehicles as much as $ 6,000 per automobile. U.S. District Judge William K. Sessions III dismissed these claims in his ruling. "The court remains unconvinced automakers cannot meet
2125-494: The California Air Resources Board passed strict greenhouse gas emission standards which are being challenged in the courts. On September 12, 2007, a judge in Vermont ruled in favor of allowing states to conditionally regulate greenhouse gas (GHG) emissions from new cars and trucks, defeating an attempt by automakers to block state emissions standards. A group of automakers including General Motors , DaimlerChrysler , and
2210-554: The F-body (Chevrolet Camaro and Pontiac Firebird) for 1995 and on the J-Body (Chevrolet Cavalier and Pontiac Sunfire) and N-Body (Buick Skylark, Oldsmobile Achieva, Pontiac Grand Am) for 1995 and 1996 and also for North American delivered 1994–1995 Saab vehicles with the naturally aspirated 2.3. The pinout for the ALDL connection on these cars is as follows: For ALDL connections, pin 9
2295-449: The 17 character VIN. Y bodies built for 1985 and later can be identified by the inclusion of the Y as the fourth character in the VIN. Only two Y-body cars have been produced in this second group: The Y-Body has a rear-wheel drive, front-engined (through 2019) V8 layout, accommodating either a small block Chevrolet V8 (such as an LT4 or LS1) in the Corvette, or the 32-valve DOHC Northstar V8 in
2380-600: The 2026 model year. EPA's air pollution score represents the amount of health-damaging and smog-forming airborne pollutants the vehicle emits. Scoring ranges from 0 (worst) to 10 (best). The pollutants considered are nitrogen oxides (NOx), particulate matter (PM), carbon monoxide (CO), formaldehyde (HCHO), and various hydrocarbon measures – non-methane organic gases (NMOG), and non-methane hydrocarbons (NMHC), and total hydrocarbons (THC). This score does not include emissions of greenhouse gases (but see Greenhouse gas score, below). EPA's greenhouse gas score reflects
2465-643: The A-body. The Buick V6 was continued and enlarged to 225 cubic inches with the basic engine remaining in production for many years, with a 3.8-liter or 231 cubic-inch displacement. The aluminum V8 was replaced by conventional cast-iron block V8s of 300 cubic inches for the Buick Special/Skylark and 330 inches for the Oldsmobile F-85/Cutlass, while Pontiac carried over its 326 cubic-inch V8 to the '64 Tempest/LeMans line while switching
2550-584: The CAA. Since the CAA's passage in 1967, California has applied and received more than fifty waivers, which include emission standards across various vehicle classes. Among these include two special sets of waivers: On September 21, 2021, CARB proposed a plan to upgrade all engines in cars, trucks, and boats to EPA "Tier 3" levels by the end of 2024, and the "Tier 4" level, which is more restrictive, by 2035. Tier 4 engine technology does not yet exist. The Sportfishing Association of California and Golden Gate Fishermen’s Association argued against this proposal on
2635-802: The Corvair as its 1960 Car of the Year, Tempest as 1961's Car of the Year, and the V6 Special received the award in 1962. Each of the Buick, Olds and Pontiac Y-body senior compacts were replaced by a larger intermediate-sized platform called the A-Body for the 1964 model year, which was shared with the Chevrolet Chevelle . With the switch from a senior compact to an intermediate-sized platform, most of these "innovative" features were discontinued such as
On-board diagnostics - Misplaced Pages Continue
2720-595: The DTC's from the vehicle. DTC's from OBD-I cars are often read through the blinking patterns of the 'Check Engine Light' (CEL) or 'Service Engine Soon' (SES) light. By connecting certain pins of the diagnostic connector, the 'Check Engine' light will blink out a two-digit number that corresponds to a specific error condition. The DTC's of some OBD-I cars are interpreted in different ways, however. Cadillac fuel-injected vehicles are equipped with actual onboard diagnostics, providing trouble codes, actuator tests and sensor data through
2805-626: The ECU. The various available parameters are addressed by "parameter identification numbers" or PID s which are defined in J1979. For a list of basic PIDs, their definitions, and the formula to convert raw OBD-II output to meaningful diagnostic units, see OBD-II PIDs . Manufacturers are not required to implement all PIDs listed in J1979 and they are allowed to include proprietary PIDs that are not listed. The PID request and data retrieval system gives access to real time performance data as well as flagged DTCs. For
2890-531: The EPA and NHTSA proposed a new "One National Program Rule" that asserted that only the federal government may set emissions standards on September 19, 2019, as to have one consistent set of fuel emission and mileage standards across the country. This rule would include revoking the last set of California waivers that the EPA had granted California in 2013 for its GHG and ZEV programs. California retained its ability to set emission standards that address ozone-formation under
2975-471: The EPA's vehicle standards. The EPA's assessment of the state of the country meeting the target NAAQS goals by 1975 was poor, having identified numerous nonattainment areas in the country. With the 1977 Amendment to the CAA, a new deadline of December 31, 1982, for meeting the NAAQS was fixed with no allowance for extending the deadline unless specific control measures were established. Among other key provisions
3060-508: The NAAQS attainment goals could optionally establish I/M programs for existing but were required to follow the EPA's specifications. Due to its preexisting standards and particularly severe motor vehicle air pollution problems in the Los Angeles metropolitan area, the U.S. state of California has special dispensation from the federal government to promulgate its own automobile emissions standards. Other states may choose to follow either
3145-485: The OBD-II Data Link Connector the only one in the vehicle through which all systems are diagnosed and programmed. OBD-II Diagnostic Trouble Codes are 4-digit, preceded by a letter: P for powertrain (engine and transmission), B for body, C for chassis, and U for network. The OBD-II specification provides for a standardized hardware interface — the female 16-pin (2x8) J1962 connector , where type A
3230-519: The OBD-II codes implemented. This hybrid system was present on GM B-body cars (the Chevrolet Caprice, Impala, and Buick Roadmaster) for 1994–1995model years, H-body cars for 1994–1995, W-body cars (Buick Regal, Chevrolet Lumina (for 1995 only), Chevrolet Monte Carlo (1995 only), Pontiac Grand Prix, Oldsmobile Cutlass Supreme) for 1994–1995, L-body (Chevrolet Beretta/Corsica) for 1994–1995, Y-body (Chevrolet Corvette) for 1994–1995, on
3315-551: The Obama-era mileage goals, Trump had expressed his intent to revoke California's waivers early on in his presidency. Shortly after Ford, Volkswagen, Honda, and BMW announced their intentions to commit to the Obama-era mileage goals and California's emission standards across their fleets in July 2019, Trump announced his intention to rollback California's waivers. As part of Trump's "Safer, Affordable, Fuel-Efficient" (SAFE) program,
3400-546: The Special Skylark and F-85 Cutlass, both of which featured bucket seats, custom interior and exterior trim, and more powerful engines. For 1962, convertibles were added to the lineup by each of the divisions, with Pontiac also adding the sportier Tempest LeMans coupe and convertible to its compact lineup. This all-new platform replaced vehicles GM was importing from Europe, selling the Vauxhall Victor that
3485-702: The Tempest's four-cylinder engine and transaxle, the aluminum block V8 (whose tooling was sold to Rover of England who improved the design enjoying considerable success with it as the Rover V8 in models such as the Rover P5B and Range Rover ) and the Olds Jetfire's turbocharged version of that V8. Also, the uni-body construction used in the Y-body cars was replaced by conventional body-on-frame construction for
On-board diagnostics - Misplaced Pages Continue
3570-596: The XLR. The Y-Body also has 4-wheel independent suspension. Like a standard rear-wheel drive, front-engined chassis, the Y-Body's V8 engine is longitudinally mounted, but unlike many such cars, the Y-Body incorporates a rear-mounted transmission (1997-present) instead of a transmission mounted directly to the engine. Power is transferred to the transmission via a torque tube. The transmission is offered in both 4/5/6/8-speed automatic versions and 6 and 7-speed manual versions. As of 2015
3655-479: The Y-body cars, but had a two-inch shorter wheelbase, was smaller in length and width and utilized a distinct X-body platform which featured semi-unibody construction, single-leaf spring rear suspension and conventional in-line four-, six-cylinder and later small-block V-8 engines. The Y-body family of cars contained more innovative features than all other American products of that decade. Each model contained at least one notable advance: Motor Trend magazine named
3740-476: The ability to monitor nitrogen oxide catalyst performance. EMD and EMD+ are similar to OBD-I in logic but use the same SAE J1962 data connector and CAN bus as OBD-II systems. Five signaling protocols are permitted with the OBD-II interface. Most vehicles implement only one of the protocols. It is often possible to deduce the protocol used based on which pins are present on the J1962 connector: All OBD-II pinouts use
3825-460: The airbag system, the selective ride control system, the low tire pressure warning system, and the passive keyless entry system. An OBD 1.5 has also been used in the Ford Scorpio since 95. OBD-II is an improvement over OBD-I in both capability and standardization. The OBD-II standard specifies the type of diagnostic connector and its pinout, the electrical signalling protocols available, and
3910-511: The amount of greenhouse gases a vehicle will produce over its lifetime, based on typical consumer usage. The scoring is from 0 to 10, where 10 represents the lowest amount of greenhouse gases. The Greenhouse gas score is determined from the vehicle's estimated fuel economy and its fuel type. The lower the fuel economy, the more greenhouse gas is emitted as a by-product of combustion. The amount of carbon dioxide emitted per liter or gallon burned varies by fuel type, since each type of fuel contains
3995-558: The authority to perform vehicle inspections programs beyond the requirements for new vehicles, though few states took their own action on this. Air pollution had become a major national focal point by 1970, leading to a major amendment to the CAA. Near the end of 1970, the United States Environmental Protection Agency (EPA) was formed out of an executive order under President Richard Nixon with ratification by Congress to consolidate all of
4080-403: The base engine from the four-cylinder to a 215 cubic-inch inline six-cylinder. Y bodies built for 1976-1980 used a GM-standard 13 character Vehicle Identification Number , or VIN, with the second character denoting the series, followed by the body type, engine code, model year and assembly plant. Y bodies built for 1981-1984 can be identified by the inclusion of the Y as the fifth character in
4165-467: The basis on the upgrades to their boats would be economically disastrous and would lead to charging their customers higher ticket cost, and affect their ability to stay in business. The two sides reached a compromise to upgrade to Tier 3 and delay the Tier 4 update for when the technology is available and cost effective. Section 177 of the CAA grants the ability for states to adopt California emission standards instead of federal ones. As of December 2021,
4250-566: The challenge of Vermont and California's (greenhouse gas) regulations," he wrote. Environmentalists pressed the Administration to grant California a waiver from the EPA for its emissions standards to take effect. Doing so would allow Vermont and other states to adopt these same standards under the Clean Air Act . Without such a waiver, Judge Sessions wrote, the Vermont rules will be invalid. In 2009, President Obama announced
4335-517: The cleanest ( zero-emission vehicle ) and 11 the dirtiest. However, bins 9, 10, and 11 are temporary. Only the first ten bins were used for light-duty vehicles below 8,500 pounds (3,900 kg) GVWR, but medium-duty passenger vehicles up to 10,000 pounds (4,500 kg) GVWR and to all 11 bins. Manufacturers can make vehicles which fit into any of the available bins, but still must meet average targets for their entire fleets. The two least-restrictive bins for passenger cars, 9 and 10, were phased out at
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#17327881040844420-436: The end of 2006. However, bins 9 and 10 were available for classifying a restricted number of light-duty trucks until the end of 2008, when they were removed along with bin 11 for medium-duty vehicles. As of 2009, light-duty trucks must meet the same emissions standards as passenger cars. Tier II regulations also defined restrictions for the amount of sulfur allowed in gasoline and diesel fuel , since sulfur can interfere with
4505-406: The environmental-related executive-branch programs to a single entity; the new agency was the primary agency for administering the CAA going forward. Among the provisions related to vehicle emissions: Additionally, the 1970 CAA Amendment continued California's waiver program through which California can seek exemptions from the EPA's emissions requirements as long as theirs are at least as strict as
4590-510: The federal government to implement clean transport options such as EVs, also committed to improving the fuel efficiency standards and reversing the Trump administration's actions. The EPA issued a new rule in December 2021, to become enforceable by February 2022, that effectively restored the Obama-era standards, through decreasing the fleet-wide emissions target to a projected 161 g CO 2 /mi by
4675-551: The federal standards. California applies for this waiver through the EPA, which publishes the proposed standards for public review in the Federal Register. Based on its own review and public comments, the EPA then grants the waiver unless it has determined that California's requested standards were "arbitrary and capricious" in their findings, that the standards are not needed to "meet compelling and extraordinary conditions", or otherwise are inconsistent with other aspects of
4760-492: The following states have adopted the California standards, including their standards for ZEV and GHG: Former President Donald Trump stated his concern about California's stricter emission standards and their impact on the costs of manufacturing on the automobile industry, though some political analysts asserted this also tied in with Trump's conservative ideology conflicting with California's more liberal stance. Along with
4845-456: The fuel economy across all of their vehicles by 5% each year. After Donald Trump was inaugurated as president in 2017, he instructed the NHTSA and EPA to rollback Obama's CAFE standards, increasing the 2026 target to a then-projected 202 g CO 2 /mi and requiring only an annual 1.5% fleet efficiency improvement. The new rule was issued in March 2020. The Trump administration argued the rollback
4930-543: The manufacturer must pay a penalty, then US$ 5.50 per 0.1 mpg under the standard, multiplied by the manufacturer's total production for the U.S. domestic market. This is in addition to any gas guzzler tax , if applicable. Should CAFE targets have been extended through to 2026 under the Obama administration, it would have sought a 54 mpg industry-wide average fuel efficiency for cars and light trucks manufactured in 2026 or later, with automobile manufacturers instructed to increase
5015-415: The messaging format. It also provides a candidate list of vehicle parameters to monitor along with how to encode the data for each. There is a pin in the connector that provides power for the scan tool from the vehicle battery, which eliminates the need to connect a scan tool to a power source separately. However, some technicians might still connect the scan tool to an auxiliary power source to protect data in
5100-471: The mid-20th century, California's economy grew rapidly after the Great Depression, but this economic development was accompanied by an increase in air pollution in the state. As a result, smog started to form in the valleys of Southern California, causing respiratory problems for humans and damaging crops.In the 1960s, Dutch chemist Arie Jan Haagen-Smit identified the air pollutants responsible for
5185-558: The national standard or the stricter California standards. The states that have adopted the California standards are: Colorado , Connecticut , Delaware , Maine , Maryland , Massachusetts , New Jersey , New Mexico (2011 model year and later), New York, Nevada , Oregon , Pennsylvania , Rhode Island , Vermont , and Washington (2009 model year and later), as well as the District of Columbia . Such states are frequently referred to as "CARB states" in automotive discussions because
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#17327881040845270-569: The new digital Electronic Climate Control display. Holding down 'Off' and 'Warmer' for several seconds activates the diagnostic mode without the need for an external scan tool. Some Honda engine computers are equipped with LEDs that light up in a specific pattern to indicate the DTC. General Motors, some 1989–1995 Ford vehicles (DCL), and some 1989–1995 Toyota/Lexus vehicles have a live sensor data stream available; however, many other OBD-I equipped vehicles do not. OBD-I vehicles have fewer DTC's available than OBD-II equipped vehicles. OBD 1.5 refers to
5355-518: The operation of advanced exhaust treatment systems such as selective catalytic converters and diesel particulate filters . Sulfur content in gasoline was limited to an average of 120 parts-per-million (maximum 300 ppm) in 2004, and this was reduced to an average 30 ppm (maximum 80 ppm) for 2006. Ultra-low sulfur diesel began to be restricted to a maximum 15 ppm in 2006 and refiners are to be 100% compliant with that level by 2010. A second round of California standards, known as Low Emission Vehicle II,
5440-459: The primary component of vehicle exhaust, carbon dioxide (CO 2 ). Since CO 2 emissions are proportional to the amount of fuel used, the national Corporate Average Fuel Economy (CAFE) regulations were historically the primary way in which automotive CO 2 emissions were regulated in the U.S. The EPA faced a lawsuit seeking to compel it to regulate greenhouse gases as a pollutant, Massachusetts v. Environmental Protection Agency . As of 2007,
5525-414: The regulation dates applied a year earlier – January 1, 2000 for petrol and January 1, 2003, for diesel. For passenger cars with a Gross Vehicle Weight rating of greater than 2500 kg and for light commercial vehicles, the regulation dates applied from January 1, 2002, for petrol models, and January 1, 2007, for diesel models. The technical implementation of EOBD is essentially the same as OBD-II, with
5610-485: The regulation dates applied a year earlier – January 1, 2005 for petrol and January 1, 2006, for diesel. The ADR 79/01 standard was supplemented by the ADR 79/02 standard which imposed tighter emissions restrictions, applicable to all vehicles of class M1 and N1 with a Gross Vehicle Weight rating of 3500 kg or less, from July 1, 2008, for new models, July 1, 2010, for all models. The technical implementation of this standard
5695-534: The regulations are defined by the California Air Resources Board . The EPA adopted the Californian fuel economy and greenhouse gas standard as a national standard by the 2016 model year and collaborated with Californian regulators on stricter national emissions standards for model years 2017–2025. Light-duty vehicles are certified for compliance with emission standards by measuring their tailpipe emissions during rigorously-defined driving cycles that simulate
5780-631: The regulations cover vehicles with test weights up to 14,000 pounds (6,400 kg). Listed in order of increasing stringency, the standards are: The last category is largely restricted to electric vehicles and hydrogen cars , although such vehicles are usually not entirely non-polluting. In those cases, the other emissions are transferred to another site, such as a power plant or hydrogen reforming center, unless such sites run on renewable energy . A set of transitional and initially voluntary "national low emission vehicle" (NLEV) standards were in effect starting in 1999 for northeastern states and 2001 in
5865-444: The rest of the country until Tier II, adopted in 1999, began to be phased in from 2004 onwards. The National Low Emission Vehicle program covered vehicles below 6,000 pounds (2,700 kg) GVWR and adapted the national standards to accommodate California's stricter regulations. Instead of basing emissions on vehicle weight, Tier II standards are divided into several numbered "bins". Eleven bins were initially defined, with bin 1 being
5950-408: The rule. General Motors Y platform The original Y bodies were: Initially, each of the Y-body compacts from Buick, Olds and Pontiac were only offered as four-door sedans and station wagons when introduced in the fall of 1960 as 1961 models. In mid-1961, each of three divisions introduced pillared two-door models to the line with sportier versions of the Buick and Olds models added including
6035-413: The same SAE J1962 diagnostic link connector and signal protocols being used. With Euro V and Euro VI emission standards, EOBD emission thresholds are lower than previous Euro III and IV. Each of the EOBD fault codes consists of five characters: a letter, followed by four numbers. The letter refers to the system being interrogated e.g. Pxxxx would refer to the powertrain system. The next character would be
6120-427: The same connector, but different pins are used with the exception of pin 4 (battery ground) and pin 16 (battery positive). OBD-II provides access to data from the engine control unit (ECU) and offers a valuable source of information when troubleshooting problems inside a vehicle. The SAE J1979 standard defines a method for requesting various diagnostic data and a list of standard parameters that might be available from
6205-478: The same for both types. These standards specifically restrict emissions of carbon monoxide (CO), oxides of nitrogen (NO x ), particulate matter (PM), formaldehyde (HCHO), and non- methane organic gases (NMOG) or non-methane hydrocarbons (NMHC). The limits are defined in grams per mile (g/mi). These standards were phased in from 1994 to 1997 and were phased out in favor of the national Tier 2 standard from 2004 to 2009. Tier I standards cover vehicles with
6290-544: The smog: carbon monoxide, hydrocarbons, and nitrogen oxides emitted from cars and factories through inefficient fuel combustion. Haagen-Smit also discovered that these air pollutants react with sunlight to form ozone , a major component of smog. As a response to this situation, the California Air Resources Board (CARB) was established in 1967 with Haagen-Smit as its first chairman. CARB set stringent vehicle emission standards to reduce air pollution in
6375-491: The state. California established the California Air Resources Board (CARB) in 1967, with Haagen-Smit as its first chairman, which among other activities set stringent vehicle emission standards by that year. Other states were also facing similar air pollution issues at the same time, but fearing that setting too strict a standard would drive away automobile manufacturers, they considered implementing standards that were less restrictive compared to California, potentially creating
6460-529: The status of the various vehicle sub-systems. The amount of diagnostic information available via OBD has varied widely since its introduction in the early 1980s versions of onboard vehicle computers. Early versions of OBD would simply illuminate a tell-tale light if a problem was detected, but would not provide any information as to the nature of the problem. Modern OBD implementations use a standardized digital communications port to provide real-time data and diagnostic trouble codes which allow malfunctions within
6545-537: The test. OBD-I was largely unsuccessful, as the means of reporting emissions-specific diagnostic information was not standardized. Technical difficulties with obtaining standardized and reliable emissions information from all vehicles led to an inability to implement the annual testing program effectively. The Diagnostic Trouble Codes (DTC's) of OBD-I vehicles can usually be found without an expensive scan tool. Each manufacturer used their own Diagnostic Link Connector (DLC), DLC location, DTC definitions, and procedure to read
6630-559: The then- Department of Health, Education, and Welfare (HEW) to encourage research and development towards reducing pollution and working with states to establish their own emission reduction programs. The CAA was amended in 1965 with the Motor Vehicle Air Pollution Control Act (MVAPCA) which gave the HEW Secretary authority to set federal standards for vehicle emissions as early as 1967. In
6715-498: The unusual event that a vehicle experiences a loss of electrical power due to a malfunction. Finally, the OBD-II standard provides an extensible list of DTCs. As a result of this standardization, a single device can query the on-board computer(s) in any vehicle. This OBD-II came in two models OBD-IIA and OBD-IIB. OBD-II standardization was prompted by emissions requirements, and though only emission-related codes and data are required to be transmitted through it, most manufacturers have made
6800-416: The vehicle to be rapidly identified. GM's ALDL (Assembly Line Diagnostic Link) is sometimes referred to as a predecessor to, or a manufacturer's proprietary version of, an OBD-I diagnostic starting in 1981. This interface was made in different varieties and changed with power train control modules (aka PCM, ECM, ECU). Different versions had slight differences in pin-outs and baud rates. Earlier versions used
6885-508: Was adopted in 1991 and was phased in from 1994 to 1997. Tier II standards were phased in from 2004 to 2009. Within the Tier II ranking, there is a subranking ranging from BIN 1–10, with 1 being the cleanest (Zero Emission vehicle) and 10 being the dirtiest. The former Tier 1 standards that were effective from 1994 until 2003 were different between automobiles and light trucks ( SUVs , pickup trucks , and minivans ), but Tier II standards are
6970-527: Was made in England. The rear-engined 1960-69 Chevrolet Corvair Z-body up to 1964 used a variation of the rear swing-axle suspension and a transaxle similar to that found on the 1961-63 Pontiac Tempest. The 1961-62 Corvair station wagons even utilized a roofline similar to that on the 1961-63 Y-body wagons. Chevrolet's front-engine compact, introduced as the Chevy II for 1962 had some dimensions similar to
7055-529: Was required due to the increasing costs of cars on consumers that higher efficiencies would only make more expensive. The move was criticized by several environmentalists, Consumer Reports , as well as the state of California, as the ruling coincided with Trump's efforts to remove the waiver for California emissions exemptions. Following Joe Biden becoming president in 2021, he signed Executive Order 14057, "Catalyzing Clean Energy Industries and Jobs Through Federal Sustainability", which in addition to committing
7140-422: Was required to monitor fuel delivery, exhaust gas recirculation, the diesel particulate filter (on diesel engines), and emissions-related powertrain control module inputs and outputs for circuit continuity, data rationality, and output functionality. EMD+ was used on model year 2010-2012 California and Federal petrol-engined vehicles with a gross vehicle weight rating of over 14,000 lb (6,400 kg), it added
7225-462: Was the establishment of required vehicle inspection and maintenance programs (I/M) in nonattainment states and optional in other areas. This required that states establish emission testing facilities for in-use vehicles to make sure they meet emissions requirements, maintained and repaired as necessary to correct any problems before their license was renewed. The EPA was tasked to establish the basic protocols for these facilities. Other states that had met
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