Description & Operation

CAUTION: To prevent damaging heating element, DO NOT scrape or apply decals to inside of rear window.

Rear window defogger is controlled by Lighting Control Module (LCM). Ignition switch must be in RUN position for rear window defogger to operate. Pressing rear window defogger switch to ON position grounds input to LCM. LCM detects the line at ground and checks ignition switch position. If module detects ignition switch in RUN position, ground is supplied to rear window defogger relay output. Rear window defogger relay is energized which closes contacts and supplies power to rear window defogger and ON indicator light on rear window defogger switch. LCM activates rear defogger relay for 10 minutes, unless rear window defogger switch is pressed to OFF position, or ignition switch is turned to LOCK position.

Principal components of the rear window defogger system are:

Heating grid on inside of rear window.
Hidden antenna module.
Lighting Control Module (LCM).
Rear defogger control switch with indicator light.
Rear window defogger relay.