GM Service Manual Online
For 1990-2009 cars only

The heating, cooling, and ventilation for the vehicle can be controlled with this system.


Object Number: 2051401  Size: B2
  1. Air Delivery Mode Controls

  2. Recirculation

  3. A/C (Air Conditioning)

  4. Temperature Control

  5. Fan Control

Temperature Control: Slide the lever towards COLD for cooler air or towards HOT for warmer air.

(Fan Control): Slide the lever right or left to increase or decrease the fan speed. Slide the fan lever to OFF to turn the system off. Outside air still comes out of the floor outlets whenever the vehicle is moving.

Air Delivery Mode Control: Press the air delivery mode buttons to change the direction of the airflow inside the vehicle. To change the current mode, select from the following:

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

(Bi-Level):  Air is divided between the instrument panel and floor outlets. Some air may be directed toward the windshield.

(Floor): Air is directed to the floor outlets, with some air directed to the outboard outlets for the side windows and windshield.

(Defog): This mode clears the windows of fog or moisture. Air is directed to the windshield and floor outlets. In this mode, the system turns off recirculation and 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 removes fog or frost from the windshield 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 turns off recirculation and runs the air-conditioning compressor, unless the outside temperature is at or below freezing. Recirculation cannot be selected while in the defrost mode.

A/C (Air Conditioning): For vehicles with air conditioning, select the fan speed, air delivery mode, and press A/C to use the air conditioning.

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. It also helps the system to operate more efficiently.

For quick cool down on hot days:

  1. Select .
  2. Select the recirculation mode.
  3. Select A/C.
  4. Select the coolest temperature.
  5. Select the highest fan speed.

Using these settings together for long periods of time may cause the air inside of the vehicle to become too dry. To prevent this from happening, after the air in the vehicle has cooled, turn the recirculation mode off. 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.

(Recirculation): Press to turn the recirculation on. The air inside the vehicle will be recirculated. For vehicles with air conditioning, using recirculation helps to quickly cool the air inside the vehicle. It can be used to help prevent outside air and odors from entering the vehicle. Recirculation is not available in Defog or Defrost modes.