General Information

The purpose of the heater is to supply heat to the interior of the vehicle. The vehicle operator can determine the level of heat by turning the temperature control, located on the HVAC control assembly, to any setting. The temperature control can change the vehicle's air temperature regardless of the HVAC mode setting, heater, A/C or OFF.

The instrument panel fuse block provides power to the air temperature actuator through the ignition 3 voltage circuit. Power and ground are provided to the HVAC control assembly by the ignition 3 voltage and ground circuits.

When a desired temperature setting is selected, a variable resistor is used to determine the air temperature actuator position signals value. The resistor changes the 12-volt signal coming into the actuator and varies the voltage to move the actuator into the proper position, based on the signal from the HVAC control assembly. The motor opens the air temperature actuator to a position to divert sufficient air past the heater core to achieve the desired vehicle temperature. Ground is provided by the ground circuit.