Test A-2: Malfunction Indicator Light (Mil) Stays On

When ignition is on, PCM energizes main relay. As PCM is supplied with ignition power, MIL turns on. After engine starts, MIL will turn off if no malfunction is detected. If a malfunction is detected, MIL will remain on until system is repaired.

1. Connect scan tool to Data Link Connector (DLC). Attempt to retrieve DTCs with ignition on, engine off. If any DTCs are displayed, see appropriate DTC. If no DTCs are displayed, go to next step.
2. Attempt to retrieve DTCs with engine running. If no DTCs are displayed, turn ignition off. Disconnect PCM connectors. Turn ignition on. If MIL comes on, repair Purple/Yellow wire between MIL bulb and PCM harness for short to ground. If MIL does not come on, replace PCM. Retest system.