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. |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 | Command the malfunction indicator lamp (MIL) ON and OFF with a scan tool. Does the MIL turn ON and OFF when commanded? | Go to Intermittent Conditions | Go to Step 3 |
3 | Replace the instrument panel cluster (IPC). Refer to Instrument Cluster Replacement . Did you complete the replacement? | Go to Step 4 | -- |
4 |
Does the vehicle operate correctly without any unwanted MIL illumination, and without any stored DTCs? | System OK | |
