Heated Element: Description and Operation

WITH HVAC C68 OR CJ2
With the ignition switch in 'RUN,', voltage is supplied to the Rear Defogger Relay Coil. Pressing the Rear Defogger Switch signals the HVAC Programmer (CJ2) or Heater and A/C Control Assembly (C61 and C67) to provide a ground path for the Rear Defogger Relay Coil. The relay energizes, closing the contact and applying voltage to the Rear Defogger and Heated Mirror(S) (if equipped). The rear window and the outside mirror(S) become warm to remove condensation from the glass surfaces.

WITH HVAC C61
With the Ignition Switch in "RUN," voltage is applied to the Heater and A/C Control Assembly. When the Rear Defogger Control Switch is pressed, a momentary enable signal is provided for the timer-relay. The timer-relay contacts close, lighting the system "ON" LED and powering the Rear Defogger and Heated Mirror(S) (if equipped). The rear window and the outside mirrors become warm to remove condensation from the glass surfaces.

ALL HVAC SYSTEMS
The first time the Rear Defogger Switch is pressed, the solid state timer (in the HVAC Programmer or HVAC Assembly) allows the Rear Defogger and Heated Mirror(S) (if equipped) to operate for approximately 10 minutes. Each time the Rear Defogger Switch is pressed thereafter, the solid state timer resets to operate for 5 minutes. The timer resets to 10 minutes when the Ignition Switch is turned "OFF," then back to "RUN." The timer also shuts off when the Rear Defogger Control Switch is pressed while the Rear Defogger and Heated Mirror(S) are already on.