Front Defrost Mode

WARNING: This page is about a different car, the 2003 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.

If the HVAC system is in front defrost mode when you turn the vehicle off, the HVAC system will restart in front defrost unless the engine is off longer than 40 minutes. If the engine is off longer than 40 minutes, the system will restart in the previous operating mode set prior to using front defrost, with outside air being drawn into the vehicle.

When FRONT DEFROST is selected, the A/C compressor is activated and outside air is brought into the vehicle. Air will be directed toward the windshield with a small amount of air toward the side window outlets. Vacuum is applied to the mode actuator through the Blue vacuum line and to the defrost actuator through the Yellow vacuum line. The mode actuator will retract, closing the Vent Door. The defroster actuator will retract, opening the Defroster Door and close the Heater Door through mechanical linkage. Recirculation mode is not available in front defrost. The rear window defogger does not affect the HVAC system at all.