Check Engine Light Related Acronyms

Below is our most current list of acronyms related to automotive check engine lights.

As time goes on we will be adding more on general repair, and some relating to other areas such as anti-lock brakes, air bag systems and more.

Please let us know if you need additional acronym information, and we will post it as quickly as possible. Thank you.

Check Engine Light Acronyms A - D

AIR : Secondary Air Injection

APP: Accelerator Pedal Position

BARO: Barometric Pressure

BPP: Brake Pedal Position

BPS: Brake Pedal Switch

BTDC: Before Top Dead Center. The location of the piston before it has reached the top of its stroke. Measured in degrees of crankshaft rotation.

CAN: Controller Area Network

CCM: Comprehensive Component Monitor

CHT: Cylinder Head Temperature

CKP: Crankshaft Position

CMCV: Charge Motion Control Valve

CMP: Camshaft Position

COP: Coil On Plug. Ignition coil on plug assembly

CPP: Clutch Pedal Position

CPU: Central Processing Unit

CV: Canister Vent Solenoid. A solenoid which seals the evaporative emission (EVAP) system from the atmosphere during EVAP monitor test.

DLC: Data Link Connector. SAE standard J1962 connector providing access to vehicle diagnostic information.

DMM: Digital Multimeter

DTC: Diagnostic Trouble Code. An alpha/numeric identifier for a concern identified by the OBD system.

Check Engine Light Acronyms E - H

ECM: Electronic Control Module

ECT: Engine Coolant Temperature

EEC: Electronic Engine Control

EEGR: Electric Exhaust Gas Recirculation System

EEPROM: Electrically Erasable Programmable Read-Only Memory. An electronic component in the PCM that allows the electronic storage of information.

EGR: Exhaust Gas Recirculation. A process in which a small amount of exhaust gas is routed into the combustion chamber.

EI: Electronic Ignition. An electronic ignition system that has the ignition control module integrated into the PCM.

EMI: Electromagnetic Interference. Usually caused by ignition voltage spikes, solenoids, relay operation, or noisy generator contacts.

EOT: Engine Oil Temperature

ERFS: Electronic Returnless Fuel System

ESM: EGR System Module

ESOF: Electronic Shift-on-the-Fly

ETB: Electronic Throttle Body

ETBTPS: Electronic Throttle Body Throttle Position Sensor

ETC: Electronic Throttle Control

EVAPCP: Evaporative Canister Purge Valve. A valve which controls the venting of fuel vapor from the evaporative emissions canister into the intake manifold for combustion.

FCIL: Fuel Cap Indicator Lamp. Indicates that the fuel filler cap is not correctly installed.

FFV: Flexible Fuel Vehicle

FLI: Fuel Level Input. Provides information on the amount of liquid fuel in the fuel tank. Used by the EVAP monitor to calculate the fuel tank vapor volume.

FMEM: Failure Mode Effects Management. Operating strategy that maintains limited vehicle function in the event of a PCM or EEC component failure.

FPDM: Fuel Pump Driver Module. A module that controls the electric fuel pump.

FPM: Fuel Pump Monitor

FRP: Fuel Rail Pressure

FTP: Fuel Tank Pressure

HO2S: Heated Oxygen Sensor. Provides information on rich or lean exhaust conditions to the PCM.

Check Engine Light Acronyms I - L

IAC: Idle Air Control. Electrical control of throttle bypass air.

IAT: Intake Air Temperature

IDM: Ignition Diagnostic Monitor

IFS: Inertia Fuel Shut-Off

IMRC: Intake Manifold Runner Control. Controls or modifies airflow in the intake air system

IMRCM: Intake Manifold Runner Control Monitor. Monitors the IMRC circuits for concerns.

INJ: Injector

ISO: International Standards Organization

KAM: Keep Alive Memory. A portion of the memory within the PCM that must have power even when the vehicle is not operating.

KAPWR: Keep Alive Power. A dedicated and un-switched power circuit that maintains KAM.

KOEO Self-Test: Key On Engine Off Self-Test. A test of the EEC system conducted by the PCM with power applied and the engine at rest.

KOER Self-Test: Key On Engine Running Self-Test. A test of the EEC system conducted by the PCM with the engine running and the vehicle at rest.

KS: Knock Sensor

LONGFT: Long-Term Fuel Trim. Fuel flow adjustment determined by the PCM.

Check Engine Light Acronyms M - P

MAF: Mass Air Flow

MAP: Manifold Absolute Pressure. The internal pressure of the intake manifold.

MIL: Malfunction Indicator Lamp. An indicator lamp alerting the driver of an EEC related concern. Also referred to as the Check Engine Light.

MRFS: Mechanical Returnless Fuel System

OHC: Overhead Cam. An engine configuration that uses a single camshaft positioned above the valves.

OL: Open Loop. An operating condition based on instructions not modified by PCM feedback.

PCM: Power train Control Module. Formerly know as the electronic engine control (EEC) processor.

PCV: Positive Crankcase Ventilation. A system which allows the controlled flow of crankcase vapors into the combustion chamber.

PID: Parameter Identifier. Identifies an address in the PCM memory which contains operating information. Helpful with check engine light diagnosis.

PIP: Profile Ignition Pickup. Provides crankshaft position information for ignition synchronization.

PSP: Power Steering Pressure. Indicates the pressure in the power steering system.

PWM: Pulse Width Modulation. Controls the intensity of an output by varying the signal duty cycle.

PWR GND: Power Ground. The main ground circuit in the EEC system.

Check Engine Light Acronyms Q - T

RAM: Random Access Memory. Memory into which information can be written as well as read.

ROM: Read-Only Memory. Computer memory that can be accessed and used, but not altered.

RPM: Revolutions Per Minute

SAE: Society of Automotive Engineers

SFI: Sequential Multiport Fuel Injection. A multiport fuel delivery system in which each injector is individually energized and timed relative to its cylinder intake event.

SHRTFT: Short-Term Fuel Trim. Fuel flow adjustment in response to the Oxygen sensors input during closed-loop operation.

SIG RTN: Signal Return. A dedicated sensor ground circuit that is common to 2 or more sensors.

TCM: Transmission Control Module

TDC: Top Dead Center

TP: Throttle Position

TSB: Technical Service Bulletin. Notifies technicians of any known vehicle concerns, procedures or general repair information.

Check Engine Light Acronyms V - Z

VCT: Variable Camshaft Timing

VECI: Vehicle Emission Control information

VIN: Vehicle Identification Number. A unique identification number given to every vehicle produced. Includes information about the year, model, engine and plant origin of the vehicle.

VMV: Vapor Management Valve.

VPWR: Vehicle Power. A switched circuit that provides power to the EEC system. Compare to battery voltage (B+)

VREF: Reference Voltage. A dedicated circuit that provides an approximate 5.0 volt signal used as a reference by certain sensors.

VRIS: Variable Resonance Induction System

WOT: Wide Open Throttle. A condition of maximum airflow through the throttle body.

Transmission Related Check Engine Light Acronyms

A/T: Automatic Transmission

CCS: Coast Clutch Solenoid

EPC: Electronic Pressure Control

ISS: Intermediate/Input Shaft Speed Sensor

OCS: Overdrive Cancel Switch

OSS: Output Shaft Speed. Indicates the rotational speed of the transmission output shaft.

PNP: Park/Neutral Position switch

SSA/SSB/SSC/SSD/SSE: Shift solenoids. Devices in an automatic transmission that control the shifting by varying fluid flow when commanded by the PCM.

TCC/TCCH: Torque Converter Clutch. When energized, causes a mechanical engagement and disengagement of the torque converter clutch.

TCIL: Transmission Control Indicator Lamp. Indicates that the TCS has been activated.

TCS: Transmission Control Switch. Modifies the operation of electronically controlled transmissions.

TFT: Transmission Fluid Temperature. Indicates the temperature of transmission fluid.

TR: Transmission Range. The range in which the transmission is operating.

TSS: Turbine Shaft Speed. Indicates the rotational speed of the transmission turbine shaft.

VSS: Vehicle Speed Sensor. A magnetic pickup device that generates an AC signal that is proportional to the vehicle speed.

Back To Top Of Check Engine Light Acronyms Page