Air Distribution - Auxiliary Control

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The auxiliary HVAC system provides ventilation for the rear seat occupants. The rear seat occupants will exercise control of the auxiliary air delivery modes, air speed and the air temperature setting. The front auxiliary HVAC control assembly will have the ability to override the rear auxiliary HVAC control module by placing it in any position other than Aux.

The auxiliary mode switch in the front auxiliary HVAC control assembly allows the driver to direct the air flow in the rear of the vehicle between the floor, headliner, or a blend between the two options. Power is provided to both the front auxiliary HVAC control assembly and the auxiliary mode actuator from the IP fuse block on the ignition 3 voltage circuit.

Voltage delivered to the front auxiliary HVAC control assembly on the ignition 3 voltage circuit is sent to a variable resistor. Based on the placement of the mode switch, a varied voltage is sent to the auxiliary mode actuator on the auxiliary mode door control circuit, and auxiliary HVAC control processor. The auxiliary mode actuator moves the mode door to the desired output. Ground for the auxiliary mode actuator, auxiliary HVAC control processor and front auxiliary HVAC control assembly are provided by the ground circuit.