A-2: Malfunction Indicator Light (Mil) Remains On

When ignition is on, main relay is energized and supplies PCM with battery voltage. 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 no DTCs are displayed, go to next step. If any DTCs are displayed, see appropriate test under DIAGNOSTIC TESTS  .
2. Attempt to retrieve DTCs with engine running. If any DTCs are displayed, see appropriate test under DIAGNOSTIC TESTS  . If no DTCs are displayed, turn ignition off. Disconnect PCM harness connectors. Turn ignition on. If MIL comes on, repair short to ground between PCM harness connector C21 terminal No. 17 and instrument cluster (Purple wire on Esteem, or Purple/Yellow wire on Swift). If MIL does not come on, replace PCM. Retest system.