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Malfunction Indicator Lamp (MIL) Inoperative



Malfunction Indicator Lamp (MIL) Inoperative

Circuit Description

The malfunction indicator lamp (MIL) is located on the instrument panel cluster (IPC).

Ignition voltage is supplied to the MIL. The powertrain control module (PCM) turns the MIL ON by grounding the MIL control circuit. There should be a steady MIL with the ignition ON and the engine OFF.

MIL Function
* The MIL informs the driver that a malfunction has occurred and the vehicle should be taken in for service as soon as possible.
* The MIL illuminates during a bulb test and a system test.
* A DTC will be stored if a MIL is requested by the PCM.

MIL Illumination
* The MIL will illuminate with the ignition switch ON and the engine OFF.
* The MIL will turn OFF when the engine is started.
* The MIL will remain ON if the self-diagnostic system has detected a malfunction.
* The MIL may turn OFF if the malfunction is not present.
* If the MIL is illuminated and then the engine stalls, the MIL will remain illuminated as long as the ignition switch is ON.
* If the MIL is not illuminated and the engine stalls, the MIL will not illuminate until the ignition switch is cycled OFF, then ON.

Test Description

Step 1 - Step 11:




The number below refers to the step number on the diagnostic table.
3. This step tests for a short to voltage on the MIL control circuit. With the fuse removed there should be no voltage on the MIL control circuit.