Heated Glass Element: Description and Operation

When the ignition switch is turned to the RUN position, voltage is applied through the HVAC/DRL Fuse in the fuse block to the rear defogger switch in the heater-a/c control. A solid state timer controls battery voltage from the HVAC/DRL Fuse in the fuse block through a relay. When the rear defogger switch is pressed, voltage is momentarily applied to the timer, activating the relay controlling the rear window defogger grid. This relay will remain closed by the timer until the defog cycle is complete or the rear defogger switch is pressed a second time.

When the ignition switch is turned to the RUN position and the rear defogger switch is pressed for the first time, the defog cycle lasts 10 minutes and further operation will result in 5 minute defog cycles. The defog cycle is reset to 10 minutes when the ignition switch is turned to the OFF position and back to the RUN position.

The defogger ON indicator is an LED that illuminates when the rear defogger is ON.