2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 245

9 (Fan Control): Turn clockwise or counterclockwise to increase or decrease the fan speed. Turn the knob all the way counterclockwise to turn the front system off. Air Delivery Mode Control: Turn clockwise or counterclockwise to change the direction of the airflow inside the vehicle. The knob can be positioned between two modes to select a combination of those modes. Select from the following: H (Vent): Air is directed to the instrument panel outlets. ) (Bi-Level): Air is divided between the instrument panel and floor outlets. 6 (Floor): Air is directed to the floor outlets, with some air directed to the windshield and side window outlets. In this mode, the system automatically selects outside air. Recirculation cannot be selected in floor mode. - (Defog): This mode clears the windows of fog or moisture. Air is directed to the windshield, floor outlets, and side window vents. 0 (Defrost): This mode removes fog or frost from the windshield more quickly. Air is directed to the windshield and the side window vents, with some air directed to the floor vents. The system automatically forces outside air into the vehicle. The recirculation mode cannot be selected in the defog or defrost mode. When either mode is selected, the system runs the air conditioning compressor, unless the outside temperature is close to freezing. Do not drive the vehicle until all the windows are clear. : (Outside Air): Press to turn the outside air mode on. An indicator light comes on to show that outside air is on. In this mode outside air circulates throughout the vehicle. The outside air mode can be used with all modes, but it cannot be used with the recirculation mode. 4-21