Engine Control Module: Description and Operation

PURPOSE
The Digifant control module determines the injector opening time based on inputs it receives from the following components:

^ The Manifold Absolute Pressure (MAP) sensor (G71)
^ The Intake Air Temperature (IAT) sensor (G42) and CO potentiometer (G74)
^ The Heated Oxygen Sensor (HO2S) (G39)
^ And the Engine Coolant Temperature (ECT) sensor (G62)

OPERATION
The Engine Control Module (ECM) J169 for the Fuel Injection and Ignition system is equipped with a Diagnostic Trouble Code (DTC) memory.

If malfunctions occur with sensors and/or components monitored by the On Board Diagnostic system, they will be stored in the DTC memory together with an indication of the type of malfunction.

Check DTC memory to display stored malfunctions. DTC memory must be erased once a malfunction has been resolved.

Malfunctions relating to the Heated Oxygen sensor control system function can only be checked after a test drive of at least 10 minutes.

Malfunctions due to a temporary open circuit in the wiring or a loose terminal, will also be stored. These malfunctions will be displayed as sporadic malfunctions "SP" and are automatically erased if they are not repeated after 40 engine starts.

Vehicles with Malfunction Indicator Lamp (MIL) ONLY
The instrument cluster MIL lamp must light up when the ignition is switched ON and go out when the engine starts. If malfunctions occur in sensors and/or components and monitoring conditions are satisfied, the MIL lamp will also light up (with engine running).