The heater system provides the following functions:

The blower fan draws outside air from the plenum at the base of the windshield into the heater module. Forward movement of the vehicle forces additional outside air, called ram air, into the heater module. Within the heater module, the air heats as required. Then, the ducts route the air to the proper outlets for the discharge into the passenger compartment. A control assembly in the instrument panel allows the operator control of the following items: