Heater Mode: Notes

WARNING: This page is about a different car, the 2002 Oldsmobile Intrigue. However, it is still accessible from the selected car via links, so may be relevant.

The purpose of the heater is to supply heat to the interior of the vehicle. The vehicle operator can determine the level of heat by turning the left air temperature switch, located on the HVAC control module, to any setting. The temperature switch can change the vehicles air temperature regardless of the HVAC mode setting, heater or A/C. The vehicle passenger can adjust their temperature by turning the right air temperature switch. Passenger temperatures can be offset 6°F (3°C) cooler or warmer than the primary setting.

The HVAC control module receives power from the fuse block on the ignition 3 voltage circuit along with the battery positive circuit. The module is grounded by the ground circuit. The HVAC control module communicates directly to the Powertrain Control Module (PCM) on the HVAC class 2 serial data circuit, through a splice pack, and through the ECM/PCM/VCM class 2 serial data circuit.