HVAC Control Module
WARNING: This page is about a different car, the 2003 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
The HVAC control module is a device that interfaces between the operator and the HVAC system to maintain air temperature and distribution settings. The control module sends switch input data to the instrument panel module (IPM), and receives display data from the IPM through signal and clock circuits. The ignition 3 voltage circuit provides a device on signal. The control module does not retain any HVAC DTCs or settings.