TrailBlazer 4WD L6-4.2L VIN S (2002)
Control Assembly: Description and Operation
HVAC Systems - Manual
Air Delivery Description and Operation
HVAC CONTROL MODULE
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. The control module supports the features:
AUXILIARY HVAC CONTROL MODULE
The auxiliary HVAC control module is a class 2 device that interfaces between the rear seat occupants and the auxiliary HVAC system to maintain
auxiliary air temperature and auxiliary air 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 auxiliary HVAC DTCs and settings will be erased from KAM. The
auxiliary HVAC control module will perform a recalibration of the electric actuators when commanded with a scan tool or if KAM is lost. This will
ensure the actuators are moving with in the calibrated range.
Air Temperature Description and Operation
HVAC CONTROL MODULE
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. The control module supports the features:
AUXILIARY HVAC CONTROL MODULE - VIN 6
The auxiliary HVAC control module is a class 2 device that interfaces between the rear seat occupants and the auxiliary HVAC system to maintain
auxiliary air temperature and auxiliary air 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 auxiliary HVAC DTCs and settings will be erased from KAM. The
auxiliary HVAC control module will perform a recalibration of the electric actuators when commanded with a scan tool or if KAM is lost. This will
ensure the actuators are moving with in the calibrated range.
