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Heated Glass Element: Description and Operation

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 deenergize and remove power from the Rear Window Defrost Grid circuit.