Air Distribution (Auxiliary) Control

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2002 GMC Yukon XL, 2002 GMC Yukon, 2002 Chevrolet Tahoe, 2002 Chevrolet Suburban, and 2002 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

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 assembly by placing it in any position other than REAR.

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 2 options. Power is provided to both the front auxiliary HVAC control assembly and the auxiliary mode actuator from the I/P 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.