Abbreviations
OBD GLOSSARY OF TERMS
A
Alternate or Equivalent Phase-in: Phase in of equivalent emission reductions by the end of the last year of the scheduled phase-in.
The emission reductions are calculated by multiplying the percent of vehicles (based on the manufacturer's projected sales volume of all vehicles and engines) meeting the new requirements per year by the number of years implemented prior to and including the last year of the scheduled phase-in and then summing these yearly results to determine a cumulative total.
B
Base Fuel Schedule: refers to the fuel calibration schedule programmed into the Powertrain Control Module or PROM when manufactured or when updated by some off- board source, prior to any learned on-board correction.
C
Catalyst Monitoring:
Non-Low Emission Vehicles: The catalyst system shall be considered malfunctioning when its conversion capability decreases to the point that HG emissions increase by more than 1.5 times the standard over an FTP test from a test run with a representative 4000 mile catalyst system.
Transitional Low Emission Vehicles TLEV: these vehicles shall employ an emission threshold malfunction criterion of 2.0 times the applicable FTP HG standard plus the emissions from a test run with a representative 4000 mile catalyst system.
Low Emission Vehicles LEV: The catalyst system shall be considered malfunctioning when its conversion capability decreases to the point that either of the following occurs:
1.Hydrocarbon (HO) emissions exceed the applicable emission threshold specified. The emission threshold criterion for LEV and ULEV applications shall be 2.5 and 3.0 times the applicable FTP HG standard, respectively, plus the emission level with a representative 4000 mile catalyst system. Notwithstanding, beginning with the 1998 model year, manufacturers shall phase in an emission threshold of 1.75 times the applicable FTP HG standard for all categories of low emission vehicles, which shall not include the emission level with a 4000 mile catalyst system.
2.The average Federal Test Procedure (FTP) Non-Methane Hydrocarbon (NMHC) conversion efficiency of the monitored portion of the catalyst system falls below 50 percent.
CARB- California Air Resources Board:The California Air Resources Board mission is to promote and protect public health, welfare and ecological resources through the effective and efficient reduction of air pollutants while recognizing and considering the effects on the economy of the state of California.
California's Legislature established the Air Resources Board (ARB) in 1967 to:
1.Attain and maintain healthy air quality.
2.Conduct research into the causes of and solutions to air pollution.
3.Systematically attack the serious problem caused by motor vehicles, which are the major causes of air pollution in the state.
Since its formation, the ARB has worked with the public, the business sector, and local governments to protect the public's health, the economy, and the state's ecological resources through the most cost-effective reduction of air pollution.
What the ARB Does: Programs for cleaner air range from research and regulation to enforcement and education. The ARB:
1.Sets And Enforces Emission Standards For Motor Vehicles ,fuels, And Consumer Products
2.Sets Health-based Air Quality Standards
3.Conducts Research
4.Monitors Air Quality
5.Identifies And Sets Control Measures For Toxic Air Contaminants
6.Provides Compliance Assistance For Businesses
7.Produces Education And Outreach Programs And Materials
8.Oversees And Assists Local Air Quality Districts Which Regulate Most Non-vehicular Sources Of Air Pollution.
For extensive information on the CARB, visit their website @http://www.arb.ca.gov
Continuous monitoring: means sampling at a rate no less than two samples per second. If for engine control purposes, computer input component is sampled less frequently, the value of the component may instead be evaluated each time sampling occurs.
"CLV" Calculated load value: A formula that refers to an indication of the current airflow divided by peak airflow, where peak airflow is corrected for altitude, if available. This definition provides a unitless number that is not engine specific, and provides the service technician with an indication of the percent engine capacity that is being used (with wide open throttle as 100%).
D
Diagnostic Link Connector (DLC): SAE standardized aftermarket scantool-vehicle interface connector. Located in the interior of the vehicle.
Drive or Driving Cycle: consists of engine start-up vehicle operation and engine shutoff.
Diagnostic Trouble Code DTC):SAE standardized OBD II fault code. This code structure is designed by the SAE to identify identical faults along all vehicle manufacture systems. These fault codes are accessed by using an aftermarket scantool via the DLC. If using the BMW DIS or MODIC, these fault codes provide no additional information already provided by the BMW diagnostic equipment.
E
Engine misfire: means lack of combustion in the cylinder due to absence of spark, poor fuel metering, poor compression, or any other cause.
Engine Start: is defined as the point at which normal, synchronized spark and fuel control is obtained or 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).
Evaporative System Monitoring:
The system is considered to be malfunctioning when:
-No purge air flow can be detected (Oxygen Sensor Feedback).
-When a leak is detected in the system that is equal to or larger than 1 mm (0.040 in).
F
Federal Test Procedure (FTP): a specific driving cycle that is utilized by the EPA to test light duty vehicles and light duty truck emissions. As part of the procedure for a vehicle manufacturer to obtain emission certification for a particular model/engine family the manufacturer must demonstrate that the vehicle(s) can pass the FTP defined driving cycle two consecutive times while monitoring various components/systems.
Some of the components/systems must be monitored either once per driving cycle or continuously.
Components/systems required to be monitored once within one driving cycle:
Oxygen Sensors
Secondary Air Injection System
Catalyst Efficiency
Evaporative Vapor Recovery System
Components/systems required to be monitored continuously:
Misfire Detection
Fuel system
Oxygen Sensors
All emissions related systems providing or receiving signals to the DME, EGS, or EML.
NOTE: Due to the complexity involved in meeting the test criteria within the FTP defined driving cycle, all tests may not be completed within one "customer driving cycle". The test can be successfully completed within the FTP defined criteria, however customer driving styles may differ and therefore may not always monitor all involved components/systems in one "trip".
Fuel trim: refers to feedback adjustments to the base fuel schedule. Short-term fuel trim refers to dynamic or instantaneous adjustments. Long-term fuel trim refers to much more gradual adjustments to the fuel calibration schedule than short-term trim adjustments. These long term adjustments compensate for vehicle differences and gradual changes that occur over time.
Functional check: for an output component means verification of proper response to a computer command. For an input component, functional check means verification of the input signal being in the range of normal operation, including evaluation of the signals rationality in comparison to all available information.
G-H-I-J
J-Specifications: The SAE established the required specifications for the EPA/ARB OBD II program. These are known as the J specs. By visiting the SAE website @ www.SAE.org, detailed information regarding the following specs can be accessed.
SAE J 1930 - Standardization of system terms, definitions abbreviations and acronyms.
SAE J 1962 - Diagnostic Link Connector pin assignments and manufacturing dimensions.
SAE J 2012 - Definitions of Diagnostic Trouble Codes (DTCs).
There are additional J specifications related to the On Board Diagnostics Program which can be obtained by purchasing the SAE On Board Diagnostics for Light and Medium duty Vehicles Standards Manual via the SAE website.
K-L
Low Emission Vehicle: refers to a vehicle certified in California as a Transitional Low Emission Vehicle (TLEV), a Low Emission Vehicle (LEV), or an Ultra Low Emission Vehicle (ULEV). These vehicle categories are further defined in Title 13, sections 1956.8 and 1960.1.
M
Malfunction: means the inability of an emission-related component or system to remain within design specifications.
Further, malfunction refers to the deterioration of any emission related components or system to a degree that would likely cause the emissions of an average certification durability vehicle with the deteriorated components or systems present at the beginning of the applicable certification emission test to exceed by more than 1.5 times any of the emission standards.
Misfire: means lack of combustion in the cylinder due to absence of spark, poor fuel metering, poor compression, or any other cause.
Misfire Monitoring: The diagnostic system shall monitor engine misfire and shall identify the specific cylinder experiencing misfire via MIL activation and fault code. If more than one cylinder is misfiring, a separate code shall indicate that multiple cylinders are misfiring plus specifying the individual misfiring cylinders.
N-O
On-Board Diagnostics: On-Board Diagnostic (OBD) Systems are incorporated into the emission related control modules (DME, EGS/AGS/EML) in new vehicles to monitor components and systems that affect emissions when malfunctioning.
California's second generation of OBD requirements (known as OBD II) have been fully in effect since the 1996 model year. OBD II systems monitor virtually every component that can affect the emission performance of the vehicle. If a problem is detected, the OBD II system illuminates a warning lamp on the vehicle instrument panel to alert the driver. This warning lamp typically contains the phrase Check Engine or Service Engine Soon. The system will also store important information about the detected malfunction so that a repair technician can accurately find and fix the problem.
Oxygen sensor "Response Rate": refers to the delay (measured in milliseconds) between a switch of the sensor from lean to rich or vice versa in response to a change in fuel/air ratio above and below stoichiometric.
P-Q-R
Redline Engine Speed: means the manufacturer recommended maximum engine speed as normally displayed on instrument panel tachometers, or the engine speed at which fuel shutoff occurs.
S
Secondary Air: refers to air introduced into the exhaust system by means of a pump or aspirator valve or other means that is intended to aid in the oxidation of HO and CO contained in the exhaust gas stream.
Small Volume Manufacturer: any vehicle manufacturer with sales less than or equal to 3000 new light-duty vehicles and medium-duty vehicles per model year based on the average number of vehicles sold by the manufacturer each model year from 1989 to 1991, except as follows;
For manufacturers certifying for the first time in California, model year sales shall be based on projected California sales. If a manufacturer's average California sales exceeds 3000 units of new light-duty and medium-duty vehicles based on the average number of vehicles sold for any three consecutive model years, the manufacturer shall no longer be treated as a small volume manufacturer and shall comply with the requirements applicable for larger manufacturers beginning with the fourth model year after the last of the three consecutive model years.
If a manufacturer's average California sales falls below 3000 units of new light-duty and medium-duty vehicles based on the average number of vehicles sold for any three consecutive model years, the manufacturer shall be treated as a small volume manufacturer and shall be subject to the requirements for small volume manufacturers beginning with the next model year.