Circuit Description
When the ignition is turned on, the Malfunction Indicator Lamp (MIL) will momentarily flash on and off, and then remain on until the engine is running if no DTCs are stored. The Powertrain Control Module (PCM) controls the MIL by providing a ground path through the MIL control circuit to turn on the MIL.
Diagnostic Aids
An intermittent can be caused by the following conditions and not set a DTC:
| • | A short within the instrument panel cluster (IPC). |
| • | A short to ground on the MIL control circuit. |
Inspect any circuitry that is suspected of causing an intermittent complaint.
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | Go to Step 2 | |
2 |
Does the MIL turn on and off when commanded? | -- | Go to Diagnostic Aids | Go to Step 3 |
3 |
Does the MIL illuminate? | -- | Go to Step 4 | Go to Step 6 |
4 |
Did you find and correct the condition? | -- | Go to Step 7 | Go to Step 5 |
5 |
Did you complete the repair? | -- | Go to Step 7 | -- |
|
Important:: The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | -- | Go to Step 7 | -- | |
7 | With the scan tool, command the MIL on and off. Does the MIL turn on and off when commanded? | -- | System OK | Go to Step 2 |
