Malfunction Indicator Lamp: Description and Operation
Check Engine Light:
PURPOSE
The "Check" engine light notifies the vehicle operator that an ECU related failure has occurred. The light is also used to extract trouble codes from the ECU.
LOCATION
The light is part of the instrument cluster.
OPERATION
When the ignition is turned on the check engine light illuminates briefly to verify operation. If a fault occurs, the light is again illuminated. If the fault is corrected the lamp will go out in about 5 seconds.