Bonneville V8-4.6L VIN Y (2004)
Control Module HVAC: Description and Operation
HVAC System-Automatic
Air Delivery
HVAC CONTROL MODULE
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 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.
Air Temperature
HVAC CONTROL MODULE
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.
BLOWER MOTOR CONTROL PROCESSOR
The blower motor control processor is an interface between the HVAC control module and the blower motor. The blower motor speed control, battery
positive voltage and ground circuits enable the control processor to operate. The HVAC control module provides a PWM signal to the control
processor in order to command the blower motor speed. The processor supplies 12 volts to the blower motor through the blower motor voltage supply
circuit. The control processor uses the blower motor ground as a low side control to adjust the blower motor speed.
