Rear Window Defogger System Components
The rear window defogger system consist of the following components:
| • | HVAC control module |
| • | RR DEFOG relay |
| • | Rear window that has a number of grid lines |
| • | Two bus bars that are attached to the inside surface of the rear window |
The supply voltage terminal and ground terminal are soldier to the bus bars.
Rear Window Defogger Operation
When you turn the ignition to the ON position, ignition 1 voltage is supplied through the IGN E fuse to the RR DEFOG relay coil. Battery positive voltage is supplied at all times to the RR DEFOG relay switch. When the rear window defogger switch is depressed, the HVAC control module illuminates the rear window defogger indicator and energizes the RR DEFOG relay by grounding the control circuit of the relay. This allows battery positive voltage through the RR DEFOG fuse to the rear window defoggers. Ground for the rear window defogger is provided by G306 or G390.
When you turn ON the ignition and press the rear window defogger switch for the first time, the defogger cycle lasts 10 minutes. Further operation results in 5 minute defogger cycles.
