Operation - Rear Window Defogger

WARNING: This page is about a different car, the 2003 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

The rear window defogger system is controlled by a switch installed with the HVAC control assembly. An amber indicator lamp in the switch button will light to indicate when the rear window defogger system is turned on. The HVAC control head circuitry, which contains the, defogger system timer logic, monitors the state of the defogger switch through a hard-wired input. The instrument cluster circuitry controls the rear window defogger system through a hard-wired control output to the rear window defogger relay. The rear window defogger timer and logic circuitry cannot be adjusted or repaired and, if faulty or damaged, the HVAC control head assembly must be replaced.

The rear window defogger system will be automatically turned off after a programmed time interval of about ten minutes. After the initial time interval has expired, if the rear window defogger switch is turned on again during the same ignition cycle, the defogger system will automatically turn off after about five minutes.

The rear window defogger system will automatically shut off if the ignition switch is turned to the Off position, or it can be turned off manually by depressing the instrument panel switch. Following are general descriptions of the major components in the rear window defogger system. Refer to the owner's manual in the vehicle glove box for more information on the features, use and operation of the defogger system.