Auxiliary Climate Control System

An auxiliary climate control system is available as optional equipment. The auxiliary climate control system operation is determined by the settings on the front or rear auxiliary climate control assembly. The auxiliary climate control assemblies include a blower motor switch, temperature control switch and air distribution mode switch, none of which can be individually serviced.

On vehicles with manual climate control the auxiliary blower motor operation is enabled when the function selector switch is in any position except OFF. The auxiliary system air can be cooled below ambient temperature only when A/C compressor operation has been requested by the settings of the climate control assembly of the base (front) system. The auxiliary system air can be heated at any time, the heater control valve does not affect the auxiliary climate control system operation.

On vehicles with DATC the auxiliary blower motor is operational regardless of the DATC system setting. The auxiliary system air can be cooled below ambient temperature only when A/C compressor operation has been requested by the settings of the DATC module. The auxiliary system air can be heated at any time, the heater control valve operation does not affect the auxiliary climate control system.

The front auxiliary climate control assembly:

• blower motor switch controls the auxiliary blower motor speed. The blower motor speed can be set to OFF, MED LO, MED HI, or HI. When the front auxiliary blower motor switch is set to REAR all control of the auxiliary climate control system functions are then transferred to the rear auxiliary climate control assembly.
• air distribution mode switch toggles airflow between the overhead vents and the floor vent by outputting signals to the auxiliary airflow mode door actuator which positions the auxiliary airflow mode door in all blower motor switch positions except REAR. Back-lit icons on the front climate control display indicate the source of the auxiliary system airflow.
• temperature control switch is a potentiometer that outputs a variable voltage to the auxiliary temperature blend door actuator to set the position of the auxiliary temperature blend door in all blower motor switch positions except REAR. The temperature of the auxiliary system air may be affected by the manual climate control assembly or DATC module settings (as equipped). When A/C compressor operation has not been initiated (A/C compressor commanded on) by the manual climate control assembly or the DATC module (as equipped), the auxiliary climate control system cannot cool the air below that of the ambient temperature.

The rear auxiliary climate control assembly:

• blower motor switch controls the auxiliary blower motor speed only when the front auxiliary climate control assembly blower motor switch is set to REAR. The blower motor speed can be set to OFF, LO, MED LO, MED HI, or HI.
• air distribution mode switch toggles airflow between the overhead vents and the floor vent by outputting signals to the auxiliary air distribution door actuator which positions the auxiliary air distribution door only when the front auxiliary climate control assembly blower motor switch is set to REAR. Back-lit icons on the rear climate control display indicate the source of the auxiliary system airflow.
• temperature control switch is a potentiometer that outputs a variable voltage to the auxiliary temperature blend door actuator to set the position of the auxiliary temperature blend door only when the front auxiliary climate control assembly blower motor switch is set to REAR. The temperature of the auxiliary system air may be affected by the manual climate control assembly or DATC module settings (as equipped). When A/C compressor operation has not been initiated (A/C compressor commanded on) by the manual climate control assembly or the DATC module (as equipped), the auxiliary climate control system cannot cool the air below that of the ambient temperature.