2009 Buick Lucerne Owner's Manual - Page 169

W (Floor/Defog): This mode clears the windows of fog or moisture. Air is directed to the floor outlets, with some air directed to the windshield and side window outlets. The system turns off recirculation and runs the air-conditioning compressor unless the outside temperature is at or below freezing. The recirculation mode cannot be selected while in the floor/defog mode. : (Outside Air): Press to let outside air enter the vehicle. An indicator light comes on to show this mode is on. Pressing ? cancels this mode. ? (Recirculation): Press to turn the recirculation mode on. An indicator light below the button comes on to show that this mode is on. 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. This mode cannot be selected while in the defog or defrost modes. If you try to select the recirculation mode, the indicator light flashes three times and turns off. Operation in this mode during periods of high humidity and cool outside temperatures may result in increased window fogging. If window fogging is experienced, select the defrost mode. PASS (Passenger Climate Control): Press to turn the passenger climate control systems on or off. When the passenger climate control system is on, the passenger temperature setting is displayed. If the PASS button is pressed to turn the passenger temperature setting off, the driver temperature setting controls the temperature for the entire vehicle. 0 (Defrost): This mode removes fog or frost from the windshield more quickly. Air is directed to the windshield and the side window outlets. The system automatically turns off recirculation and runs the air-conditioning compressor, unless the outside temperature is at or below freezing. Recirculation cannot be selected while in the defrost mode. # (Air Conditioning): Press to turn the air conditioning system on or off and override the automatic system. An indicator light below the button comes on to show that this mode is on. 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. 3-29