Operation CHARM: Car repair manuals for everyone.

Control Assembly: Description and Operation

AIR DELIVERY
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 ignition 3 voltage circuit provides a device on signal. Three integrated potentiometers control mode and air temperature door positions and blower motor speed. The control assembly communicates the mode door position to the vacuum control assembly through 5 solenoid control circuits. The control module supports the features as in the table.



AIR TEMPERATURE
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 ignition 3 voltage circuit provides a device on signal. Three integrated potentiometers control mode and air temperature door positions and blower motor speed. The control assembly communicates the mode door position to the vacuum control assembly through five solenoid control circuits. The control module supports the features as in the table.