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Malfunction Indicator Lamp (MIL) Always On



MALFUNCTION INDICATOR LAMP (MIL) ALWAYS ON

CIRCUIT DESCRIPTION
The engine control module (ECM) turns the malfunction indicator lamp (MIL) ON by sending a request over the CAN line.

MIL OPERATION
The MIL is located on the instrument panel cluster (IPC).

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 diagnostic.

MIL Illumination
- The MIL will illuminate with the ignition switch ON and the engine not running.
- 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 no longer 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

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