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: 1974368  Size: G8
  1. Fan Control

  2. Temperature Control

  3. Air Delivery Mode Control

  4. Rear Window Defogger

  5. Air Conditioning

  6. Recirculation

(Fan Control): Turn clockwise or counterclockwise to increase or decrease the fan speed. Turn the knob all the way counterclockwise to turn the system off.

Temperature Control: Turn clockwise or counterclockwise to increase or decrease the temperature inside the vehicle.

Air Delivery Mode Control: Turn the knob to change the current airflow mode.

Select from the following:

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

(Bi-Level): Air is divided between the instrument panel outlets and the floor outlets.

(Floor): Air is directed to the floor outlets with some air directed to the windshield and side window outlets.

(Defog): Air is directed to the windshield, floor outlets, and side window vents. Use this mode to clear the windows of fog or moisture and warm the passengers.

(Defrost):  Air is directed to the windshield, with some air directed to the side window vents. Use this mode to quickly remove fog or frost from the windshield. When defrost is selected, the air conditioning turns on automatically to improve defrosting performance. In this mode the air conditioning cannot be turned off and the recirculation mode cannot be turned on.

Air Conditioning

(Air Conditioning): Press to turn on or off. An indicator comes on when the air conditioning is on. The fan must be on to use the air conditioning. The air conditioning cannot be turned off in defrost mode. If is pressed, the indicator light flashes three times and the air conditioning stays on.

For quick cool down on hot days, select the following settings together:

  1. Press to turn on the air conditioning.
  2. Press to turn on the recirculation.
  3. Select the coolest temperature and highest fan speed.
  4. Open the windows briefly to let hot air escape and then close them.
  5. Once the vehicle's interior cools down, turn off the recirculation, and select . This maintains the best comfort level during extended driving.

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.

The air conditioning should be turned on for at least five to ten minutes once every two weeks to lubricate the air conditioning seals, even in the winter.

Recirculation

(Recirculation): Press to change the air intake between recirculated air and outside air. An indicator light comes on when the recirculation is on. The recirculation mode recycles interior air and is not recommended for extended use. If it is used for a long period of time, the system automatically lets some fresh air into the vehicle for ventilation. The recirculation mode cannot be turned on in defrost mode. If is pressed, the indicator light flashes three times and recirculation stays off.

Rear Window Defogger

The rear window defogger uses a warming grid to remove fog from the rear window. It only works when the ignition is in ON/RUN.

(Rear Window Defogger): Press to turn on or off. An indicator comes on when the rear window defogger is on. The rear window defogger turns off automatically if it is left on.

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.