For 1990-2009 cars

### Diagnostic Aids

• | An Intermittent problem may be caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation.

• | Any circuitry, that is suspected as causing the intermittent complaint, should be thoroughly checked for the following items:

- | Improper mating

- | Broken locks

- | Poor terminal to wiring connections

- | Physical damage to the wiring harness

### Test Description

The number(s) below refer(s) to the step number(s) on the Diagnostic Table.

1. The Powertrain OBD System Check prompts you to complete some of the basic checks and to store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data captured when the fault occurred. The scan tool stores this data for later reference.

2. If the volts telltale lamp is not operating, the IPC or the BFC is malfunctioning.

3. If no malfunctions are present at this point, refer to Diagnostic Aids for additional checks and information.

#### PCM Controlled Warning Lamps

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | Go to Step 2 | Go to Powertrain On Board Diagnostic (OBD) System Check
2 | Was a DTC P1601 or P1610 set? | -- | Go to applicable DTC table | Go to Step 3
3 | Turn ON the ignition leaving the engine OFF. Is the volts telltale lamp on the IPC illuminated? | -- | Go to Step 4 | Go to Step 5
4 | Start the engine. Did the volts telltale lamp on the IPC turn OFF? | -- | Go to Step 6 | Go to Step 5
5 | Check if any Body Function Controller (BFC) DTCs are set. Are any BFC DTCs set? | -- | Go to Diagnostic Trouble Code (DTC) List/Type . | Go to Body Control Module System Check .
6 | Operate the vehicle within the conditions under which the original symptom was observed. Does the system now operate properly? | -- | System OK | Go to Step 2