HVAC Control Module

The HVAC control module works in a dual role operating both air temperature and A/C operation from the drivers side switch. The HVAC control module is a class 2 device that interfaces between the operator and the HVAC system to maintain air temperature and distribution settings. The battery positive voltage circuit provides power that the control module uses for keep alive memory (KAM). If the battery positive voltage circuit loses power, all HVAC DTCs and settings will be erased from KAM. The body control module (BCM), which is the vehicle mode master, provides a device on signal. For information on the BCM serial data messages and discrete signals. Refer to Body Control System Description and Operation in Body Control System. The control module supports the following features: