Rear Defogger: Description and Operation

CAUTION: Grid lines can be damaged or scraped off with sharp instruments. Care should be taken in cleaning glass or removing foreign materials, decals or stickers. Normal glass cleaning solvents or hot water used with rags or toweling is recommended.

Rear Window Defogger - Typical:

The heated window system consists of a back glass with two vertical bus bars and a series of electrically connected grid lines fired onto the inside surface of the glass.

The heated window system is turned ON or OFF by a control switch and a timing circuit, which are combined into a single push-button switch located on the accessory switch bezel at the center of the instrument panel, below the radio.

Circuit protection is provided by a cartridge fuse located in the Power Distribution Center (PDC) for the heated grid circuit, and by a fuse in the fuse block for the control circuit.

When the rear window defogger switch is turned to the ON position, current is directed to the rear defogger grid lines and the heated power mirrors (if equipped). The heated grid lines heat the glass to help clear the surface of fog or frost.

The defogger system is controlled by a momentary switch located in the accessory switch bezel on the instrument panel. An amber indicator lamp in the switch will illuminate to indicate when the defogger system is turned on. The rear window defogger switch also contains the defogger system control circuitry including the timer logic and the defogger relay.

NOTE: The rear window defogger turns off automatically after 10 minutes of initial operation. Each following activation cycle of the defogger system will last five minutes.

The 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 defogger switch is turned on again during the same ignition cycle, the defogger system will automatically turn off after about five minutes.

The 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 defogger switch a second time. Refer to the owner's manual in the vehicle glove box for more information on the features, use and operation of the defogger system.