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Heated Glass Element: Description and Operation


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

Pressing the momentary defrost switch ON closes the contacts of the Rear Window Defrost Relay and start the ten minute (approximate) timing cycle. Current now flows to the Rear Window Defrost Grid. When the Rear Window Defrost Switch is released from ON, the solid state circuitry keeps the defrost relay coil energized.

Pressing the Rear Window Defrost Switch OFF turns off the defrost relay. This removes power from the Rear Window Defrost circuit. If the OFF switch is not pressed, power will remain on until the time delay runs out. The coil will deenergize and remove power from the Rear Window Defrost Grid circuit.