Operation CHARM: Car repair manuals for everyone.

Heated Glass Element: Description and Operation

With the Ignition Switch in RUN, Voltage is supplied to the Rear Defogger Switch at the Heater/HVAC Control Module. When the Rear Defogger Switch (R. DEF) is depressed, the contact closes, which provides Voltage to the ON Indicator Light Emitting Diode (LED) and the Rear Defogger Grid. The Rear Windows will become warm to remove fog from the surface of the window.

The Solid State Time Delay will automatically turn-off the Defogger Grids and the LED at the end of approx. 10 minutes. The Defogger Grids are also automatically turned off if the D. Fog Switch is depressed again or the Ignition Switch is placed in OFF.

For the Suburban or Utility with Cargo Doors, the Defogger Grids can only be energized with the Cargo Doors closed.