Rear Window Defog/Heated Mirror/Front Wiper De-Ice
WARNING: This page is about a different car, the 2002 Dodge Grand Caravan, 2002 Dodge Caravan, 2002 Chrysler Voyager, and 2002 Chrysler Town & Country. However, it is still accessible from the selected car via links, so may be relevant.
The defroster button located on the HVAC control, controls the rear window defogger, heated side view mirrors and front wiper de-icer grid. In addition the front wiper de-ice function is turned on when front defog/defrost mode is selected.
When the defroster button is pushed, the HVAC control sends a bus message over the PCI bus to the Front Control Module (FCM) which controls the Rear Window Defogger relay. The defroster LED will illuminate when the defroster function is on. The defroster will function for 10 minutes or can be cycled off sooner by pressing the defroster button again. The front wiper de-icer grid receives its 12 volts from the accessory relay through fuse No. 11 and the HVAC control module supplies the grid ground.