Control Module HVAC: Description and Operation

General Description

- The control module (A /CCM) is located on the right hand side of the heater unit.

- A digital micro-processor within the A/CCM receives data signals from operator controlled switches. Comparison of these signals with those returned from system temperature sensors and feedback devices results in the appropriate output voltage changes needed to vary: Blower motor speed, Flap position, and those Solenoids which respond to operator selected temperature demand.

- The A/CCM is a non servicable item but may be interrogated for system tests. Care must be exercised when connecting test equipment, the A/CCM may be irreparably damaged should any of the test pins be shorted or bent.





1 A/C control module (A/CCM)
2 Differential temperature control
3 Temperature control
4 Blower motor switch
5 Ambient temperature sensor
6 Motorized in-car aspirator
7 Evaporator temperature sensor
8 Solar/alarm sensor
9 Coolant temperature switch
10 Lower flap feedback potentiometer
11 Upper flap feedback potentiometer
12 Left blower motor feedback
13 Right blower motor feedback
14 High speed relay
15 High speed relay
16 Compressor ctutch
17 Blower motor
18 Blower motor
19 Lower flap servo motor
20 Upper flap sevo motor
21 Defrost vacuum solenoid
22 Auto recirculation vacuum solenoid
23 Center vent vacuum solenoid
24 Water valve vacuum solenoid
25 Manual recirculation vacuum solenoid (not connected to A/CCM)

NOTE: Items 21, 22, 23, 24 are encased in a single unit which is non servicable. Item 6 was formerly known as the In-car temperature sensor.