The most commonly used abbreviations for OBDII

OBD Codes

When discussing OBD-II (On-Board Diagnostic) systems, there are several commonly used abbreviations and acronyms that are important to understand. These abbreviations help simplify communication and discussion about vehicle diagnostics and troubleshooting. Here are some of the most commonly used abbreviations for OBD-II:

AFC – Air Mass Flowmeter
ALDL – Diagnostic connector. So used to be the diagnostic connector for GM cars, as well as the scanner connector; can also be used as the name of any OBD II signals
CAN – Controller
CARB – California Council for Atmospheric Resources
CFI – Central Fuel Injection (TBI)
CFI – continuous fuel injection
CO – is carbon monoxide
DLC – Diagnostic connector
Driving Cycle – The sequence of starting, warming up and driving the car, during this cycle, all OBD II functions are tested
DTC – trouble code
ECM – Engine Control Module
EEC – Electronic engine management
EEPROM or E2PROM – Programmable memory, read-only
EFI – electronic fuel injection
EGR – Exhaust gas recirculation
EMR – electronic unit for reducing the angle of ignition
EPA – Council for the Protection of the Environment
ESC – Electronic ignition control
EST – Electronic ignition timing adjustment
Fuel Trim – balancing the composition of the mixture
HC – is a hydrocarbon
HEI – ignition
HO2S – Heated Oxygen Sensor
ISO 9141 – international standard for the OBDII connector
J1850PWM – protocol for the OBD II connector, installed according to the SAE standard
J1850VPW – protocol for the OBD II connector, installed according to the SAE standard
J1962 – standard for the diagnostic connector OBD II, installed according to the SAE standard
J1978 – SAE standard for OBD II scanners
J1979 – SAE standard for diagnostic modes
J2012 – SAE standard, approved by the EPA, for messages when testing the exhaust system
MAF – air flowMAP – absolute pressure in the intake manifold
MAT – inlet manifold air temperature
MIL – fault indicator lamp. Lamp “Check Engine Light” on the instrument panel.
NOx – Nitric Oxide
O2 is oxygen
OBD – Diagnostics
OBDII or OBD II – is an advanced standard for vehicle diagnostics in the USA after 1-1-96
Parameters – Parameters for OBD II diagnostics
PCM – Transmission Control Module
PCV – Carter
Proprietary Readings – On-board computer parameters that are not required for OBD II diagnostics, but can be used to diagnose faults of different types of vehicles.
PTC – trouble code
RPM – revolutions / minute
Scan Tool – scanner
SES – service lamp of the engine on the instrument panel
SFI – sequential fuel injection
Stoichiometric Ratio – Coefficient of combustion of fuel
TPS – Throttle Position Sensor
VAC – vacuum
VCM – central control unit for the car
VIN – vehicle identification number
VSS – speed sensor
WOT – open throttle

Understanding these abbreviations and acronyms is essential for effective communication and troubleshooting when dealing with OBD-II systems. They help technicians and vehicle owners identify and discuss specific components, systems, and diagnostic codes, enabling efficient diagnosis and repair of vehicle issues.