When the mode control knob is in the VENT position, outside air is delivered through the instrument panel outlets to ventilate the passenger compartment, as shown by the symbol.

When the mode control knob is in the BI-LEV position, the airflow is split between the instrument panel outlets and the floor air outlets, with a small amount going to the defroster outlets and the side window defogger outlets, as shown by the symbol.

When the mode lever or control knob is in the HTR position, most of the airflow is directed to the floor outlet(s) with a small amount remaining being routed to the windshield defroster and the side window defogger outlets, as shown by the symbol. The HTR mode is the normal selection for cold weather operation unless the windshield must be cleared of heavy frost.

When the mode control knob is in the BLEND position, the defroster valve moves into an intermediate range to uncover more of the opening to the defroster, as shown by the symbol. As a result, an increasing amount of air flows to the defroster nozzle and a decreasing amount goes to the heater duct.

When the mode control knob is in the DEFROST position, most of the airflow is directed to the windshield defroster outlets, as shown by the symbol. This will allow a much smaller amount to go to the floor air outlet(s). The side window defogger outlets receive the same air supply as in the HTR mode.