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

(Power): Press this button to turn the climate control system on or off. When the climate control system is turned off the air inlet defaults to outside air.

Automatic Operation

AUTO (Automatic): When this button is pressed and the temperature is set, the system automatically controls the inside temperature, the air delivery mode, the air conditioning compressor, and the fan speed. When the indicator light is on, the system is in full automatic operation. If the air delivery mode or fan setting is manually adjusted, the auto indicator turns off and displays will show the selected settings.

1. Press the AUTO button.
2. Adjust the temperature to a comfortable setting between 60°F (15.5°C) and 90°F (32.2°C).

Choosing the coldest or warmest temperature setting will not cause the system to heat or cool any faster. If the system is set at the warmest temperature setting, it remains in manual mode at that temperature and it will not go into automatic mode.

In cold weather, the system starts at reduced fan speeds to avoid blowing cold air into the vehicle until warmer air is available. The system begins blowing air at the floor but may change modes automatically as the vehicle warms up to maintain the chosen temperature setting. The length of time the system needs to warm up depends on the outside temperature and the length of time that has elapsed since the vehicle was last driven.

3. Wait for the system to regulate. This may take from 10 to 30 minutes. Then adjust the temperature, if necessary.

You can switch from English to metric units through the Driver Information Center (DIC). See DIC Vehicle Customization .

The air-conditioning system removes moisture from the air, so a small amount of water might drip underneath the vehicle while it is idling or after the engine is turned off is normal.

Do not cover the solar sensor located in the center of the instrument panel, near the windshield. For more information on the solar sensor, see "Sensors" later in this section.

PASS (Passenger Climate Control): Press this button to set a different temperature for the passenger. Then press the passenger temperature adjustment buttons to select a comfortable setting. Pressing the PASS button again automatically sets the passenger's temperature to the driver's setting. Turning the passenger's temperature display off does not shut the climate control system for the passenger off.

/ (Temperature Adjustment): The temperature can be adjusted separately for the driver and the passenger. Press the up or down arrow buttons to increase or decrease the automatic temperature settings.

Manual Operation

(Mode): Press the or buttons to change the current airflow mode. The current mode selection appears in the display screen. Changing the mode cancels the automatic operation and the system goes into manual mode. Press AUTO to return to automatic operation. The outboard air outlets always receive some airflow in every mode, except defrost. See Outlet Adjustment to change this airflow from the outboard outlets.

(Vent): This mode directs air to the instrument panel outlets.

(Bi-Level): This mode splits the air between the instrument panel outlets and the floor outlets. In automatic operation, cooler air is directed to the upper outlets and warmer air to the floor outlets.

(Floor): This mode directs most of the air to the floor outlets with some air directed to the outboard outlets and a little air directed to the windshield. The mode buttons can also be used to select the defog and defrost modes. Information on defogging and defrosting can be found later in this section.

(Fan): Press the or buttons to increase or decrease the fan speed. Pressing either button cancels automatic operation and the system goes into manual mode. Press AUTO to return to automatic operation. The blower may reduce during an Onstar® session to limit background noise. If the airflow seems low when the fan speed is at the highest setting, the passenger compartment air filter might need to be replaced. For more information, see Passenger Compartment Air Filter and Scheduled Maintenance .

(Air Conditioning): Press this button to override the automatic system and turn the air conditioning system on or off. When in AUTO, the air conditioning compressor will come on automatically, as necessary. The air conditioning system removes moisture from the air, so a small amount of water might drip underneath the vehicle while idling or after turning off the engine. This is normal.

/ (Recirculation/Outside Air): Press this button to switch between recirculation and outside air. Whenever the button is pressed, the indicator light comes on for the mode being used. The recirculation mode recirculates air inside the vehicle. It can be used to prevent outside air and odors from entering the vehicle or to help cool the air inside the vehicle more quickly. Press the auto button to have the system select the best air delivery mode for your temperature setting. Recirculation is not available in the defrost mode and automatically turns off 10 minutes after defog is selected. This helps to limit window fogging in the vehicle. Using recirculation for long periods of time could cause the air inside the vehicle to become too dry or stuffy. To prevent this from happening, after the air in the vehicle has cooled, select outside air or press the auto button. The outside air mode pulls fresh air from outside the vehicle. Outside air is always selected in defrost mode to prevent fogging.

(Heated Windshield Washer, If Equipped): For more information, see Windshield Washer .

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 from the windshield. 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.

(Mode): Press the mode buttons until defog appears on the display.

(Defog): This mode directs the air between the windshield, floor outlets and side windows. When this mode is selected, the system turns off recirculation and runs the air-conditioning compressor unless the outside temperature is at or below freezing. If recirculation mode is selected while in defog mode, it will be cancelled after 10 minutes.

(Defrost): Pressing defrost directs most of the air to the windshield, with some air directed to the side windows. In this mode, the system automatically turns off recirculation and runs the air-conditioning compressor, unless the outside temperature is at or below freezing. This mode may also cause the fan speed and air temperature to increase.

Rear Window Defogger

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

The rear window defogger will only work when the ignition is in ON/RUN.

(Rear Window Defogger): Press this button to turn the rear window defogger on or off. Be sure to clear as much snow from the rear window as possible.

The rear window defogger turns off about 15 minutes after the button is first pressed if the vehicle is moving at slower speeds. At higher speeds, the rear window defogger may stay on continuously. With each additional press, the defogger runs for about 10 minutes. The defogger can also be turned off by pressing the button again or by turning off the engine.

The heated outside rearview mirrors will heat to help clear fog or frost from the surface of the mirror when the rear window defogger button is on. See Outside Heated Mirrors .

Notice: Do not try to clear frost or other material from the inside of the front windshield and rear window with a razor blade or anything else that is sharp. This may damage the rear window defogger grid and affect your radio's ability to pick up stations clearly. The repairs wouldn't be covered by your warranty.

Sensors

There is a solar sensor, located on the instrument panel, near the windshield.

There is also an interior temperature sensor, located to the right of the steering wheel, on the instrument panel.

By monitoring the solar radiation and the air inside the vehicle, these sensors help maintain the selected temperature by adjusting the fan speed, and the air delivery system. In order to do this, the system can also supply cooler air to the side of the vehicle facing the sun. The recirculation mode will also be activated, as necessary. Do not cover the sensors or the automatic climate control system will not work properly.