GM Service Manual Online
For 1990-2009 cars only

The climate control system allows manual control of the heating, cooling, and ventilation in the vehicle.


Object Number: 871865  Size: B2

Fan

(Fan): Turn the knob by this symbol, located on the left side of the climate control panel, clockwise or counterclockwise to increase or decrease the fan speed. During the highest fan speed selections, the fan speed will be temporarily reduced between the transition to a new mode. The fan will resume the original speed when the transition to the new mode is complete.

(Off): Turn the knob to this position to turn the fan off.

Mode

Turn the middle knob to select the following modes:

(Vent) Outside Air: This mode directs outside air to the instrument panel outlets. If driving in city traffic, and the vehicle is stopped and idling, or the weather is hot, switch from this mode to the recirculation mode. To prevent the air inside the vehicle from becoming stale, be sure to return to the vent mode periodically.

(Bi-Level): This mode directs half of the air to the instrument panel outlets, and the remaining air to the floor outlets. Some air may be directed toward the windshield. Slightly cooler air is directed to the instrument panel outlets and warmer air is directed to the floor outlets.

(Floor): This mode directs most of the air to the floor outlets with some air directed toward the side window outlets and a little air directed to the windshield. In this mode, the system will automatically use outside air. The air conditioning compressor will be engaged unless the outside temperature is 40°F (4°C) or below. Recirculation cannot be selected when in this mode. The middle knob on the climate control panel can also be used to select the defog or defrost mode.

Defogging and Defrosting

Fog on the inside of the vehicle is a result of high humidity causing moisture to condense on the cool window glass. This can be minimized if the climate control system is used properly. There are two modes to clear frost or fog from the windshield. Use the defog mode to clear the windows of condensation and to warm the vehicle's occupants. Use the defrost mode to remove frost or condensation from the windshield quickly. Recirculation cannot be selected when in these modes.

See "Rear Window Defogger" later in this section for information on clearing the rear window of fog or ice.

(Floor/Defog): Use the floor/defog mode to clear the windows of fog or moisture and to warm the passengers. This mode directs the air equally between the windshield and the floor outlets, along with some directed to the side window outlets. This mode will automatically use outside air. The air conditioning compressor will be engaged unless the outside temperature is 40°F (4°C) or below.

(Defrost):  Use the defrost mode to remove fog or frost from the windshield more quickly. This mode directs most of the air to the windshield and the side window outlets, with some air directed to the floor outlets. This mode has a timer and will shut off after five minutes. This mode will automatically use outside air. The air conditioning compressor will be engaged unless the outside temperature is 40°F (4°C) or below.

Temperature

The knob on the right of the climate control panel is the temperature adjustment that can be used with any of the climate control modes.

Turn the knob clockwise for warmer settings and counterclockwise for colder settings.

Air Conditioning

(Air Conditioner): Press this button on the climate control panel to turn the air conditioning compressor on or off. An indicator light to the right of the button will come on to show that the air conditioning is on. This button has no control over the air conditioning compressor when in the other modes. The instrument panel brightness control may have to be adjusted to the highest setting in order to see the indicator. See Instrument Panel Brightness for additional information.

On hot days during the vehicle's initial start-up, 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 quicker cool down on hot days, do the following:

  1. Select the vent/outside air mode.
  2. Select the recirculation mode.
  3. Select the air conditioner.
  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 the vehicle to become too dry. To prevent this from happening, select the vent mode once the interior of the vehicle is cooled.

The air conditioning system removes moisture from the air, so sometimes there may be a small amount of water dripping underneath the vehicle while it is idling or after the engine is turned off. This is normal.

Recirculation

(Recirculation): Press this button on the climate control panel to activate the recirculation mode. With this selection, inside air is recirculated into the vehicle along with some outside air. This mode reduces outside air and odors from entering the vehicle. It may also help to heat or cool the air inside the vehicle more quickly. An indicator light to the right of the button will come on to show that the recirculation mode is on. The instrument panel brightness control may have to be adjusted to the highest setting to see the indicator. The recirculation mode has a timer. After five minutes, the system's air inlet door will move slightly to allow for ten percent fresh outside air to maintain interior air quality. The only way to reset the system to full recirculation is to restart the five minute timer by selecting vent/outside air and recirculation again.

Rear Window Defogger

The rear window defogger uses a warming grid to remove fog or frost from the rear window. Be sure to clear as much snow from the rear window as possible.

Notice: Do not use a razor blade or sharp object to clear the inside rear window. Do not adhere anything to the defogger grid lines in the rear glass. These actions may damage the rear defogger. Repairs would not be covered by your warranty.

(Rear Window Defogger): Press this button to turn the rear window defogger on or off.

An indicator light to the right of the button will come on to show that the rear window defogger is on. The instrument panel brightness control may have to be adjusted to the highest setting during the daytime in order to see the indicator light.

The rear window defogger will turn off approximately 20 minutes after the button is pressed. If the button is pressed again, it will run another 20 minutes. The defogger can be turned off by pressing the button again or by turning off the engine.

Do not drive the vehicle until all windows are clear.