Operation CHARM: Car repair manuals for everyone.

Control Assembly: Description and Operation

CLIMATE CONTROL ASSEMBLY

The climate control assembly has three system controls:
- The function selector switch combines a vacuum selector valve with two electrical switches to supply battery positive voltage to the A/C clutch circuit (if equipped with A/C) and the blower motor control circuit.
- The temperature selection is accomplished with a potentiometer connected to the electric temperature blend door actuator that controls positioning of the temperature blend door. Movement of the control knob from COOL (Blue) to WARM (Red) causes a corresponding movement on the air temperature control door and determines the temperature that the system will maintain.
- The blower motor switch controls blower motor speed by adding or bypassing resistors in the heater blower motor switch resistor.