Circuit Description
Battery positive voltage is supplied directly to the malfunction indicator lamp (MIL) . The powertrain control module (PCM) turns the MIL ON by grounding the MIL control circuit.
MIL Operation
The MIL is located on the instrument panel (IP).
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 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 not present. |
| • | If the MIL is illuminated and then the engine stalls, the MIL will remain illuminated so 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. |
Diagnostic Aids
If the problem is intermittent, refer to Intermittent Conditions .
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |
Is the MIL illuminated? | Go to Step 3 | Go to Step 5 | |
3 |
Did you find and correct the condition? | Go to Step 6 | Go to Step 4 |
4 | Replace the IPC. Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console. Did you complete the replacement? | Go to Step 6 | -- |
5 | Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | Go to Step 6 | -- |
6 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
