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Malfunction Indicator Lamp: Testing and Inspection

MIL CIRCUIT

CIRCUIT DESCRIPTION

The MIL is used to indicate the ECM's detection of a vehicle malfunction.

The instrument panel GAUGE fuse provides circuit power and the ECM provides the circuit ground that illuminates the MIL.

MIL operations should be checked visually:

The MIL should be illuminated when the ignition switch is first turned ON. If the MIL is always ON or OFF, use the hand-held tester or OBD II scan tool and follow the procedures below to determine the cause of the problem.

Wiring Diagram:






INSPECTION PROCEDURE




Step 1 - 4:






HINT: Troubleshoot each trouble symptom in accordance with the chart.