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Heated Glass Control Module: Description and Operation

SYSTEM OPERATION
Defogger Switch, Relay, And Timer Module
The rear window defogger switch, relay, and timer are integrated into a single module. The module is mounted in the heater-A/C control bezel on the instrument panel. The switch, relay, and timer circuit is protected by a fuse in the fuse block module.

Actuating the momentary switch energizes the relay and electronic timer circuit. This causes electrical current to flow through the rear window glass heating grid circuit for approximately ten minutes, or until the rear window defogger switch or ignition switch are turned to the Off position. An amber Light-Emitting Diode (LED) in the switch bezel illuminates to indicate when the defogger system is turned on.

The defogger switch, relay, and timer module cannot be repaired. If faulty or damaged, the entire module must be replaced.