GM Service Manual Online
For 1990-2009 cars only

Uplevel Climate Controls shown, Base similar


Object Number: 1240606  Size: B2

With this system you can control the heating, cooling, and ventilation for your vehicle.

Temperature Knob

The left knob on the control panel is used to adjust the temperature of the air in the vehicle. Turn the knob clockwise or counterclockwise to increase or decrease the temperature.

Fan Knob

(Fan): The center knob on the control panel is used to control the fan speed. Turn the knob clockwise or counterclockwise to increase or decrease the fan speed.

If the knob is set on "0" (zero), some outside air will still enter the vehicle and will be directed according to the position of the mode knob.

Mode Knob

The right knob on the control panel is used to direct the airflow inside your vehicle. Turn the knob to select one of the following modes:

(Vent): Select this mode to direct air to the instrument panel outlets.

(Bi-Level): Select this mode to direct approximately half of the air to the instrument panel outlets, and the remaining air to the floor outlets and the defroster and side window outlets. Cooler air is directed to the upper outlets and warmer air to the floor outlets.

(Floor): Select this mode to direct air to the floor outlets. Recirculation is disabled in this mode because interior window could fog under some conditions. If this occurs, see "Defogging and Defrosting" following.

Mode Buttons

(Recirculation): If your vehicle has air conditioning, you will have the recirculation feature. This mode recirculates air inside the cabin, and prevents outside air from coming in the vehicle. It can be used to prevent outside odors from entering your vehicle and cool the air inside your vehicle more quickly. Press this button to turn the recirculation mode on or off. An indicator light on the button will come on to let you know the recirculation mode is activated. Recirculation is only available in the bi-level and vent modes. It should only be used while in bi-level and vent modes. Recirculation is not available, and the light will not come on or flash while in heat, floor, floor/defog, or defrost modes.

(Air Conditioning): Your vehicle may have air conditioning. Press this button to turn the air-conditioning system on or off. An indicator light on the button will come on to let you know the air conditioning is activated. When the system is on, this setting cools and dehumidifies the air entering your vehicle.

The air conditioning will not function if the fan is turned off.

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

The air conditioning system removes moisture from the air, so you may sometimes notice a small amount of water dripping underneath your vehicle while idling or after turning off the engine. This is normal.

Defogging and Defrosting

Fog on the inside of windows is a result of high humidity (moisture) condensing on the cool window glass. This can be minimized if the climate control system is used properly. There are two modes to clear fog or frost from your windshield and side windows. Use the defog mode to clear the windows of fog or moisture and warm the passengers. Use the defrost mode to remove fog or frost from the windshield more quickly. For best results, clear all snow and ice from the windshield before defrosting.

Turn the mode knob on the climate control panel clockwise to select the defog or defrost modes.

(Floor/Defog): This mode directs the air to the windshield, the side window outlets, and to the floor outlets. When you select this mode, the system runs the air conditioning compressor unless the outside temperature is near freezing or below. Recirculation is not available in this mode.

(Defrost): This mode directs most of the air to the windshield, and the side window outlets. When you select this mode, the system runs the air conditioning compressor unless the outside temperature is near, or below freezing. Recirculation is not available in this mode.

Do not drive the vehicle until all the windows are clear.