Heated Glass Element Switch: Description and Operation
REAR WINDOW DEFOGGER SWITCHThe Rear Window Defogger Switch is a momentary contact switch. Toggling the switch results in the A/C-Heater Control sending a signal to the BCM to provide rear window defogger activation or deactivation respectively. The switch LED illuminates when the switch is ON.
The rear window defogger control switch and circuit are integrated into the HVAC control assembly. Refer to the HVAC control assembly for additional information.
When actuating the switch it sends a ground signal to the Body Control Module (BCM). The BCM actuates the relay allowing current to flow through the grid lines for 15 minutes upon initial actuation. Then 10 minutes with each subsequent actuation or until either the switch or ignition is turned OFF. An indicating lamp illuminates the rear window defogger switch.