Auxiliary HVAC Control Functions
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All Auxiliary functions and DTCs are handled by the HVAC Control Module. There are two ways the rear functions can be controlled.
Control from the HVAC Control Module: If the AUX button on the HVAC Control Module is pressed, the auxiliary HVAC system will be enabled. The settings for the auxiliary will mimic the driver settings on the HVAC control module.
Control from the Auxiliary HVAC Control Module: If at any time any of the three auxiliary controls are adjusted, control of the rear HVAC system will transfer to the auxiliary controls. If the Aux button is not currently enabled, adjusting the auxiliary controls will enable it, even if the front system is OFF.