Malfunction Indicator Lamp: Service and Repair

Bulb Test

- The check engine lamp will be illuminated when the ignition switch is placed in the ON position.

- When the engine is started, the light should turn OFF.

Code Set

- If the lamp remains ON for 10 seconds or constantly after the engine is started, the self diagnosis system has detected a problem and has stored a code in the system Electronic Control Module (ECM).

Clearing Codes

- After diagnosis and repair, the ECM memory can be cleared of codes, by disconnecting battery ground cable for 10 seconds, with ignition switch in the OFF position.