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.

The rear window defogger system, also known as electrical backlight (EBL), consists of two vertical bus bars and a series of grid lines fired onto the inside surface of the rear window.

Rear Window Defogger Switch:

The EBL 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.

Circuit protection is provided by a fuse located in the power distribution center (PDC) for the heated grid circuit, and by a fuse in the junction block (JB) for the control circuit.

The electric backlight (EBL) system is controlled by a momentary switch located in the accessory switch bezel on the instrument panel. When the defogger switch for the EBL system is pressed 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 rear window and side mirror surfaces of fog or frost.

An amber indicator in the defogger switch will illuminate to indicate when the EBL system is turned on. The rear window defogger switch contains the EBL system control circuitry including the timer logic and the defogger relay.

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

The EBL 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 EBL system will automatically turn off after about five minutes.

The EBL 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.