2008 Chevrolet Tahoe Owner's Manual - Page 198

6(Floor): This mode directs most of the air to the floor outlets, with some of the air directed to the windshield, side window outlets, and second row floor outlets. In this mode, the system will automatically select outside air. Recirculation cannot be selected when in Floor Mode. The right knob can also be used to select defog or defrost mode. For more information, see "Defogging and Defrosting" later in this section. By positioning the right knob between two modes, a combination of those two modes is selected. The air conditioning compressor will be on unless the outside temperature is close to freezing. This mode keeps outside air from entering the vehicle. It can be used to reduce outside air and prevent odors from entering the vehicle. Recirculation may also help cool the air inside the vehicle more quickly once the temperature inside the vehicle is less than the outside temperature. The recirculation mode cannot be used with floor, defrost, or defogging modes. If you try to select recirculation in one of those modes, the indicator will flash three times and turn off. The air conditioning compressor will also come on when this mode is activated. While in recirculation mode the windows may fog when the weather is cold and damp. To clear the fog, select either the defog or defrost mode and increase the fan speed. Recirculation mode can be turned off by pressing the button again, or turning off the engine. AUX (Auxiliary): Pressing this button will turn the rear heating and air conditioning on. See Rear Air Conditioning and Heating System on page 3-33 or Rear Air Conditioning and Heating System and Electronic Climate Controls on page 3-35 for more information. 9(Fan): Turn the left knob clockwise or counterclockwise to increase or decrease the fan speed. Turn the knob all the way counterclockwise to turn the front system off. Press this button to turn the recirculation mode on. When the button is pressed, an indicator light will come on. ?(Recirculation): 3-24