• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Rear Defrost Relay B+ | 2 | 2 | -- | -- |
Rear Defrost Switch Signal | B3743 5A | 2 | 2 | -- |
Rear Defog Relay Control | B0283 00 | B0283 00 | B0283 00 | -- |
Rear Defog Indicator Control | B0969 02 | 3 | B0969 01 | -- |
Rear Defogger Grid Control | 2 | 2 | 1 | -- |
Rear Window Defogger Grid Ground | -- | 2 | 2 | -- |
1. Rear Defogger Always On 2. Rear Defogger Inoperative 3. Rear Defogger Indicator Inoperative |
The instrument panel cluster (IPC) monitors the voltage level in the rear window defog indicator control circuit. The voltage level should be low while the rear window defog indicator is illuminated and the voltage will be near system voltage when the rear window defog indicator is not illuminated.
Battery voltage must be between 9-16 volts.
The IPC detects a short to ground in the rear window defog indicator control circuit.
The IPC detects a short to voltage in the rear window defog indicator control circuit.
The rear window defog indicator will be continuously illuminated.
The rear window defog indicator will be inoperative.
• | The DTC will be current for as long as the fault is present. |
• | When the fault is no longer present, the DTC will be a history DTC. |
• | A history DTC will clear after 50 ignition cycles. |
Rear Window Defogger Description and Operation
Control Module References for scan tool information
Command the Rear Window Defog LED Test ON and OFF with the scan tool. The rear window defog indicator should turn ON and OFF when changing between the commanded states.
⇒ | If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the IPC. |
⇒ | If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the IPC. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for IPC replacement, setup, and programming |