Engine Control Module
The computer that runs the engine: reading sensors, commanding injection, ignition, throttle and emissions equipment, and talking to the other modules on the vehicle. Two things about it are worth holding when diagnosing. It supplies a precise regulated reference voltage to most analogue sensors, and one reference circuit feeds several sensors at once — so when that supply fails, four or five sensors report faults together and every one of them is healthy. And its own internal faults are far more often caused by supply problems, poor earths or water ingress than by failed silicon, so the charging system and earths deserve checking before an expensive module is condemned and coded.
Also known as: ecm, ecu, pcm, engine ecu, powertrain control module, engine management module, engine computer, brain
Referenced by 531 codes
Codes involving this component (531)
- P2105 Throttle Actuator Control System — Forced Engine Shutdown Stop driving Critical
- P025A Fuel Pump Module A Control Circuit/Open Stop driving High
- P025C Fuel Pump Module A Control Circuit Low Stop driving High
- P02CC Cylinder 1 Fuel Injector A Offset Learning At Min Limit High
- P02CD Cylinder 1 Fuel Injector A Offset Learning At Max Limit High
- P02CE Cylinder 2 Fuel Injector A Offset Learning At Min Limit High
- P02CF Cylinder 2 Fuel Injector A Offset Learning At Max Limit High
- P02D0 Cylinder 3 Fuel Injector A Offset Learning At Min Limit High
- P02D1 Cylinder 3 Fuel Injector A Offset Learning At Max Limit High
- P02D2 Cylinder 4 Fuel Injector A Offset Learning At Min Limit High
- P02D3 Cylinder 4 Fuel Injector A Offset Learning At Max Limit High
- P02D4 Cylinder 5 Fuel Injector A Offset Learning At Min Limit High
- P02D5 Cylinder 5 Fuel Injector A Offset Learning At Max Limit High
- P02D6 Cylinder 6 Fuel Injector A Offset Learning At Min Limit High
- P02D7 Cylinder 6 Fuel Injector A Offset Learning At Max Limit High
- P02EE Cylinder 1 Injector Circuit Range/Performance High
- P02EF Cylinder 2 Injector Circuit Range/Performance High
- P02F0 Cylinder 3 Injector Circuit Range/Performance High
- P02F1 Cylinder 4 Injector Circuit Range/Performance High
- P032F Combustion Engine Producing Insufficient Torque High
- P0601 Internal Control Module Memory Checksum Error High
- P0602 Control Module Programming Error High
- P0604 Internal Control Module Random Access Memory (RAM) Error High
- P0605 Internal Control Module Read Only Memory (ROM) Error High
- P0606 Engine Control Module Processor High
Other components in Engine Management and Sensors
Information, not instruction
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