Malfunction Indicator Lamp: Service and Repair

The CHECK ENGINE LAMP will be illuminated when the ignition switch is placed in the "ON" position. When the engine is started, the lamp should turn "OFF". 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 Control Module.

After diagnosis and repair, the ECM memory can be cleared of codes by removing the Control Module fuse or disconnecting the battery ground cable for approximately 30 seconds, with ignition switch in the "OFF" position.
NOTE
- If battery ground cable is disconnected to clear codes, components such as clocks, electronically tuned radios etc., will have to be reset.
- It is a good idea to record preset radio stations before disconnecting the negative battery cable. This will allow the stations to be reset as to not inconvenience the customer.