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Heated Glass Element: Description and Operation

Circuit Description

With TACS
Battery voltage is supplied to the rear window defogger timer at all times from fuse 9. When the engine is running, battery voltage is also supplied from the generator to the solid state controller. Depressing the rear defogger switch (when the engine is running) momentarily grounds the on/off input terminal of the timer and the solid state controller turns on the rear window defogger, Left/Right power outside mirror defogger and the rear defogger indicator. The solid state controller will turn the rear defogger off after approximately 20 minutes. Depressing the rear defogger switch when the rear defogger is on causes the timer to turn the rear defogger off.

With ETACS
Battery voltage is supplied to the defogger relay coils and contacts at all times from fuse 9 and battery voltage is also supplied from the generator to the ETACM when the engine is running. The rear defogger switch on (depressing) signal is provided to the ETACM and then ETACM provide ground to the defogger relay coil. Fuse 9 supply battery voltage to the rear window defogger and Left/Right power outside mirror defogger through defogger relay contacts. The ETACM will turn the rear defogger off after approximately 20 minutes. Depressing the rear defogger switch when the rear defogger is on causes the ETACM to turn the rear defogger off.