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 (EBL) Grid:

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

The EBL system is turned On or Off by a switch in the A/C-heater control located at the center of the instrument panel and by a timing circuit integral to the body control module (BCM).

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

Rear Window Defogger Switch:

The electric backlight (EBL) system is controlled by a momentary switch located in the A/C heater control on the instrument panel. When the rear window defogger switch is pressed to the On position, the body control module (BCM) energizes the rear window defogger (EBL) relay, which then directs fused battery current through the relay and to the rear defogger grid lines and the heated side view mirrors, when equipped. The grid lines heat the glass to help clear the rear window and side mirror surfaces of fog or frost.

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

NOTE: The EBL system turns off automatically after ten 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 an initial 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 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 pressing the rear window defogger switch a second time.

Repair of the rear window defogger grid lines, bus bars, terminals or pigtail wires can be accomplished using the Mopar Rear Window Defogger Repair Kit (Part Number 04549275) or equivalent.