GM Service Manual Online
For 1990-2009 cars only

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

Climate Control System with Heater and Air Conditioning


Object Number: 2073147  Size: B2
  1. Temperature Control

  2. Fan Control

  3. Air Delivery Mode Control

  4. Air Conditioning (A/C)

  5. Recirculation

  6. Rear Window Defogger

Climate Control System with Heater Only


Object Number: 2073158  Size: B2
  1. Temperature Control

  2. Fan Control

  3. Air Delivery Mode Control

  4. Rear Window Defogger

  5. Outside Air/Recirculation

OFF: Turns the fan off.

Temperature Control: Turn clockwise or counterclockwise to increase or decrease the temperature of the air flowing from the system.

(Fan Control): Turn clockwise or counterclockwise to increase or decrease the fan speed. The fan must be turned on to run the air conditioning compressor.

Air Delivery Mode Control: Turn clockwise or counterclockwise to change the current airflow mode.

Select from the following air delivery modes:

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

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

(Floor): Air is directed to the floor outlets, with some air directed to the rear outlets. Keep the area under the front seats clear to allow the flow of air to the rear compartment.

(Defog): This mode clears the windows of fog or moisture. Air is directed to the windshield, floor, and side window outlets. When this mode is selected, the system automatically runs the air-conditioning. To defog the windows faster, turn the temperature control to the warmest setting.

(Defrost): This mode quickly clears the windshield of fog or frost. Air is directed to the windshield and side window outlets. When this mode is selected, the system automatically runs the air-conditioning. To defrost the windows faster, turn the temperature control to the warmest setting. Do not drive the vehicle until all the windows are clear.

A/C (Air Conditioning): For vehicles with air conditioning, follow these steps to use the system. Turn to the desired speed. The air conditioning does not operate when the fan control knob is in the off position. Press A/C to turn the air conditioning on and off. When A/C is pressed, an indicator light comes on to show that the air conditioning is on.

For quick cool down on hot days, do the following:

  1. Open the windows to let hot air escape.
  2. Press .
  3. Press A/C.
  4. Select the coolest temperature.
  5. Select the highest 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): 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. For vehicles with a recirculation button, press the button to turn the recirculation mode on. An indicator light comes on to show that the recirculation is on. Press the button again to return to outside air mode. For vehicles with a lever, move the lever to choose the recirculation mode. Using the recirculation mode for extended periods may cause the windows to fog. If this happens, select the defrost mode.

(Outside Air): This mode brings outside air into the vehicle. For vehicles with a recirculation button, press the button until the recirculation mode is turned off. The vehicle then returns to the outside air mode. For vehicles with a lever, move the lever to choose the outside air mode.

Rear Window and Outside Mirror Defogger

For vehicles with a rear window and outside mirror defogger, they only work when the ignition is turned to ON/RUN.

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

(Rear Window Defogger): Press to turn the rear window and outside mirror defogger on or off. An indicator light comes on to show that the feature is on. If the vehicle does not have air conditioning, the rear window defogger may turn off about 10 minutes after the button is pressed. If it remains on, it can be turned off by pressing again or by turning off the engine. If the vehicle has air conditioning, the rear window defogger turns off about 10 minutes after the button is pressed. The defogger can also be turned off by turning the engine off.

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.