A/C Passenger Compartment Components Part 1

A/C Passenger Compartment Components (Legend) Part 2

• select air inlet source (outside or recirculated).
• select blower motor speed.
• select discharge air temperature (temperature blend).
• select discharge air location (defrost, panel, floor).
• select A/C compressor clutch operation.

• 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 manually-controlled 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.

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.

• The assembly is located on the passenger side of the plenum assembly behind the glove compartment.
• Three resistance elements are mounted on the resistor board to provide four A/C blower motor speeds.
• Depending on the heater blower motor switch position, series resistance is added or bypassed in the A/C blower motor circuit to decrease or increase A/C blower motor speed.
• An overheating protective device (thermal limiter) will open the resistor coil circuit when the temperature reaches 121°C (250°F) interrupting the blower motor operation in all speeds except HI.
• The thermal limiter cannot be reset and is not serviceable.

The heater blower motor switch resistor has the following features:

• The assembly is located on the passenger side of the A/C evaporator housing behind the glove compartment.
• Three resistance elements are mounted on the resistor board to provide four A/C blower motor speeds.
• Depending on the heater blower motor switch position, series resistance is added or bypassed in the A/C blower motor circuit to decrease or increase A/C blower motor speed.
• An overheating protective device (thermal limiter) will open the resistor coil circuit when the temperature reaches 121°C (250°F) interrupting the blower motor operation in all speeds except HI.
• The thermal limiter cannot be reset and is not serviceable.

• engine cooling fan
• A/C clutch
• fuel pump
• powertrain control module power

The powertrain control module can interrupt A/C compressor operation through the constant control relay module under the following conditions:

• during engine start-up
• Wide Open Throttle (WOT)
• low engine idle conditions
• excessively high engine temperatures

Heated Back Window Switch
The heated back window switch is a component of the Integrated Control Panel (ICP) and cannot be repaired separately. Refer to windows and Glass/Heated Glass Element to repair the heated back window system.