2009 GMC Canyon Owner's Manual - Page 147

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. Air Delivery Mode Control: Turn the knob clockwise or counterclockwise to change the current airflow mode. Select from the following modes: Do not drive the vehicle until all the windows are clear. # (Air Conditioning): Press to turn the air conditioning system on or off. An indicator light on the button comes on to show that the air conditioning is on. The fan control must be on to use the air conditioning. There might be 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 a small amount of water might drip under the vehicle while idling or after turning off the engine. This is normal. H (Vent): Air is directed to the instrument panel outlets. \ (Bi-Level): Air is divided between the instrument panel outlets and floor and side window outlets. Cooler air is directed to the upper outlets and warmer air to the floor outlets. Air is directed to the floor outlets. Recirculation cannot be selected while in floor mode because this could cause the interior window to fog. [ (Floor): / (Floor/Defog): This mode clears the windows of fog or moisture. Air is directed to the floor, windshield, and side window outlets. When this mode is selected, the system runs the air conditioning compressor unless the outside temperature is near freezing or below. Recirculation is not available in this mode. @ (Recirculation): Press to turn the recirculation mode on or off. An indicator light on the button comes on to show that the recirculation 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. The recirculation mode cannot be used with floor/defog, defrost, or defogging modes. If recirculation is selected in these modes, the indicator will flash or not come on. This mode clears the windshield of fog or frost more quickly. Air is directed to the windshield and side window outlets. When this mode is selected, the system runs the air conditioning compressor unless the outside temperature is near, or below freezing. Recirculation is not available in this mode. 0 (Defrost): 3-19