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Malfunction Indicator Lamp: Description and Operation

PURPOSE
The check engine light is used to notify the driver a fault has occurred and provide a method of code retrieval.

LOCATION
The light is built into the instrument cluster.

OPERATION
The check engine light comes on when the ignition key is turned on. Once the engine is started, the light will extinguish if no faults are present. Voltage is received from the instrument panel circuit with the ECU controlling the ground.