Check Engine Light: Notes

All vehicles are equipped with a CHECK ENGINE light, located on the instrument panel. The light will illuminate when the ignition switch is turned to the ON position (bulb check) and engine is not running. Light should not flash at this time and should go out when engine is started.

When the CHECK ENGINE engine light remains on or flashes, with the engine running, the self-diagnostic system has detected a problem. If the problem goes away, the light will go out after 10 seconds, but a trouble code will remain stored in the ECM memory.

If an EGR failure occurs and then the system returns to normal operation, the CHECK ENGINE light will remain on until the ignition switch is turned to OFF position.

The ECM will flash CHECK ENGINE light to indicate 2 digit codes. If no codes are in memory, Code 12 will flash. This indicates system is working normally and there is no other code(s) in memory. If other codes exists, the lowest numbered code will flash 3 times. This will be followed by the next highest code flashing 3 times until all codes are displayed.

When vehicle is equipped with an Electronic Spark Advance (ESA) module (no vacuum advance) in the ignition system, Code 41 will not be stored in ECM memory. Code 41 does not apply to ESA equipped Metro.