Control Assembly, HVAC

Figure 1:

Temperature Lever

The temperature lever controls the amount of air flow to the heater core, regulating the temperature of the air entering the vehicle (Figure 1).

When the temperature lever is moved completely to the left or full COLD (blue) position, the air mix door closes to block the flow of air to the heater core.

With the lever moved completely to the right or full HOT (red) position, the air mix door opens fully to allow the air to flow through the heater core.

Moving the temperature lever in between these two extremes allows the driver to adjust the passenger compartment temperature to the most comfortable level.

Mode Lever

The mode lever allows the driver to route air into the passenger compartment through different outlets (Figure 1). The mode lever operates as follows:

1. Ventilation-In this position, air is discharged from the upper air outlet. Air quantity is controlled by the blower speed control lever. Air quantity is also affected by vehicle speed when the fresh/recirc lever is set in FRESH: the faster the vehicle moves, the more air is delivered inside the passenger compartment. Also, some air is delivered even when the blower speed is in the OFF position.
2. Bi-Level-In this position, airflow is divided between the upper air outlets and the floor air outlets, with warmer air delivered to the floor outlets than is delivered to the upper air outlets.
3. Heat-In this position, air is directed toward the floor outlet, along with a small amount to the windshield.
4. Heat/Defroster-In this position, a portion of the heated air is routed to the windshield while the remaining is delivered to the floor and side window outlets.
5. Defrost-In this position, most of the air is directed to the windshield, with a small amount delivered to the side windows and to the floor.

Blower Speed Lever

The blower speed lever regulates the amount of air delivered into the passenger compartment. The blower speed lever has five positions: OFF and speeds one through four (Figure 1). The blower motor is housed in the blower case and located behind the right side of the I/P.

Fresh/Recirc Lever

The fresh/recirc lever determines whether fresh outside air or recirculated passenger compartment air enters the vehicle's beater and ventilation system.

Moving the fresh/recirc lever to the recirculate position provides the quickest air delivery by closing the blower mode door (Figure 1). In this position, outside air is not delivered to the passenger compartment. Because the vehicle is equipped with a "full-time outside air system," a small amount of outside air constantly enters the passenger compartment. Recirculate mode is helpful in heating up faster the passenger compartment. However, during normal heater operation, use fresh mode to prevent window fogging.