GM Service Manual Online
For 1990-2009 cars only

This system controls the heating, cooling, and ventilation for the vehicle.


Object Number: 2039254  Size: B3
  1. Fan Control

  2. Driver Side Temperature Control

  3. Passenger Side Temperature Control

  4. Air Delivery Mode Control

  5. Heated Seats

  6. Air Conditioning

  7. Rear Climate Control

  8. Rear Window Defogger

(Off): Turn the fan control all the way counterclockwise to turn the front system off.

(Fan Control): Turn clockwise or counterclockwise to increase or decrease the fan speed.

Temperature Control:  Use the driver and passenger levers to increase or decrease the air temperature inside the vehicle.

Air Delivery Mode Control: Turn clockwise or counterclockwise to change the current airflow mode. To change the mode, select one of the following:

MAX A/C (Maximum Air Conditioning): Turn the air delivery mode knob to this position for maximum air conditioning. This selects the air conditioning and recirculation modes for maximum cooling of the vehicle.

Recirculation: This mode recirculates and helps to quickly cool the air inside the vehicle. It can be used to prevent outside air and odors from entering the vehicle. This mode is automatically selected when MAX A/C is turned on.

(Vent): Air is directed to the instrument panel outlets.

(Bi-Level):  Air is divided between the instrument panel and floor outlets. Some air is directed towards the windshield and side window outlets.

(Floor):  Air is directed to the floor outlets. Use this mode to send air to the rear of the vehicle. Keep the area under the front seats free of objects that could obstruct airflow to the rear of the vehicle.

(Defog):  This mode clears the windows of fog or moisture. Air is directed to the windshield and the floor outlets. When this mode is selected, the system runs the air-conditioning compressor unless the outside temperature is at or below freezing. The recirculation mode cannot be selected while in the defog mode.

(Defrost):  This mode clears the windshield of fog or frost more quickly. Air is directed to the windshield and the side window outlets, with some air directed to the floor outlets. In this mode, the system automatically runs the air-conditioning system, unless the outside temperature is at or below freezing. Recirculation cannot be selected while in the defrost mode. Do not drive the vehicle until all the windows are clear.

(Air Conditioning):  Press to turn the air conditioning system on or off. The fan must be on to operate the air conditioning. An indicator light comes on when the air conditioning is on.

A slight change in engine performance may be noticeable when the air conditioning turns off and on again. This is normal. The system is designed to make adjustments to help with fuel economy while still maintaining the selected temperature.

On hot days, open the windows to let hot inside air escape; then close them. This helps to reduce the time it takes for the vehicle to cool down so the system operates more efficiently.

The air conditioning system removes moisture from the air, so a small amount of water might drip under the vehicle while idling or after turning off the engine. This is normal.

Outside Air: Outside air is automatically selected in any mode, except maximum air conditioning.

Rear Window Defogger

The rear window defogger uses a warming grid to remove fog from the rear window.

Rear Window Defogger:  Press to turn the rear window defogger on or off. An indicator light comes on when the rear window defogger is on.

The rear window defogger turns off about 15 minutes after the button is pressed. If turned on again, the defogger will only run for about five minutes before turning off. The defogger can also be turned off by turning off the engine.

Notice: Do not use anything sharp on the inside of the rear window. If you do, you could cut or damage the warming grid, and the repairs would not be covered by the vehicle warranty. Do not attach a temporary vehicle license, tape, a decal or anything similar to the defogger grid.

(Heated Seats): Press to turn on the heated seats. See Heated Seats for additional information.