Heated Glass Element: Description and Operation

With the Ignition Switch in RUN, the Rear Window Defrost Control is powered through Fuse 5.

Pressing the momentary defrost switch ON closes the contacts of the defrost relay and starts the ten minute (approximate) timing cycle. Current now flows to the Rear Window Defrost Grid. When the defrost switch is released from ON, the solid state circuitry keeps the defrost relay coil energized. Pressing the defrost switch to OFF turns off the defrost relay. This removes power from the defrost circuit. If the OFF switch is not pressed, power will remain on until the time delay runs out. Then the coil will deenergized and remove power from the Rear Window Defrost Grid circuit.