Malfunction Indicator Lamp: Testing and Inspection

Check Engine Light Schematic:

To test the Check Engine Light, located in the instrument cluster, turn the ignition switch on. The light should illuminate. This insures that the light is operative. If the light bulb does not illuminate the most likely fault is a defective light bulb. If the light tests good the other possible causes are, the ECU not supplying ground at terminal 64, the wiring harness, or the instrument cluster printed circuit board (refer to ELECTRICAL AND ELECTRONIC DIAGRAMS).