General Description

The purpose of the optional auxiliary A/C is to supply cool air and reduce the humidity to the vehicle's rear interior. The vehicle operator can determine the temperature of the A/C air by using the temperature control. A 5-volt reference signal is sent out over the 5-volt reference circuit to the auxiliary air temperature actuator. When a desired temperature setting is selected, a variable resistor is used to determine the auxiliary air temperature door position signals value. That varied 5-volt reference signal is sent back to the HVAC module software inside the HVAC control module on the auxiliary air temperature door position sensor signal circuit. The HVAC module uses this reference voltage to determine the auxiliary air temperature actuator position through the auxiliary air temperature door position signal circuit. The motor opens the auxiliary air mixture door to a position to divert sufficient air past the evaporator to achieve the desired vehicle temperature. Warm heater air is mixed with cool A/C air at the air mixture door. When the coldest temperature setting is selected, a 5-volt reference signal is sent and no warm heater air is mixed with the cool A/C air.

The left instrument panel fuse block provides power to the auxiliary air temperature actuator through the ignition 3 voltage circuit and right instrument panel junction block. Ground is provided by the ground circuits and a splice pack.