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Control Assembly: Description and Operation






The climate control assembly has three system controls:
- The A/C heater function selector switch combines a vacuum selector valve with two electrical switches to supply battery positive voltage (B+) to the A/C clutch circuit and the blower motor control circuit.
- The temperature selection is accomplished with a potentiometer connected to the electric 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 by passing resistors in the heater blower motor switch resistor.







Climate Control Assembly
The following Systems are grouped together into a single integrated control panel:
- in-vehicle entertainment
- clock
- heated back window
- climate control

The climate control assembly has three system controls:
- The A/C heater function selector switch combines a vacuum selector valve with two electrical switches to supply battery positive voltage (B+) to the A/C clutch circuit and the blower motor control circuit.
- The temperature selection is accomplished through cable controlled positioning of the temperature blend door located in the heater core housing.
- The blower motor switch controls blower motor speed by adding or by passing resistors in the heater blower motor switch resistor.