Check Engine/Malfunction Indicator (MIL) Light

The Malfunction Indicator Lamp (MIL) is intended to alert the driver in the event of certain malfunctions in the Electronic Engine Control (EEC) system.

NOTE: When the Powertrain Control Module (PCM) is in Diagnostic Test Mode, the MIL will also flash diagnostic trouble codes.

System OK
The MIL will remain ON while the key is in the ON position, and will go OFF once the vehicle has started.

System Not OK
If the MIL remains ON after the vehicle has started, perform Key On Engine Off test to completion.

- If the MIL remains ON, go to Pinpoint Test PGC, PGC - Power and Ground Connections

- If the MIL never comes ON, go to Pinpoint Test MIL, MIL - Malfunction Indicator Light (MIL)

- If the MIL comes on for a short period, then goes OFF and a diagnostic trouble code is present, the fault is intermittent.

If an engine control system fault occurs, the system processor will substitute a value or values and continue operating. This process is Limited Operating Strategy (LOS).