2007 GMC Acadia Owner's Manual - Page 205

When AUTO is selected, the air conditioning operation and air inlet are automatically controlled. The air conditioning compressor runs when the outside temperature is over about 40°F (4°C). The air inlet is normally set to outside air. If it is hot outside, the air inlet can automatically switch to recirculate inside air to help quickly cool down your vehicle. The light comes on the recirculation button while in recirculation. 2. Set the driver's and passenger's temperature. To find your comfort setting, start with a 73°F (23°C) temperature setting and allow about 20 minutes for the system to regulate. Use the driver's or passenger's temperature buttons to adjust the temperature setting as necessary. If you choose the temperature setting of 60°F (15°C), the system remains at the maximum cooling setting. If you choose the temperature setting of 90°F (32°C), the system remains at the maximum heat setting. Choosing either maximum setting will not cause the vehicle to heat or cool any faster. Do not cover the solar sensor located on the top of the instrument panel near the windshield. This sensor regulates air temperature based on sun load and also turns on your vehicle's headlamps. For more information on the solar sensor, see "Sensors" later in this section. To avoid blowing cold air in cold weather, the system delays turning on the fan until warm air is available. The length of delay depends on the engine coolant temperature. Press the fan switch to override this delay and change the fan to a selected speed. O (On/Off): Press this button to turn off the climate control system. Outside air still enters the vehicle, and is directed to the floor. This direction can be changed by pressing the mode button. Recirculation can only be selected in vent or bi-level mode. The temperature can also be adjusted using either temperature button. If you adjust the air delivery mode or temperature settings with the system off, the display comes on briefly to show the settings and then turns off. Press the on/off button or the up down arrows on the fan switch, the defrost button, AUTO button, or the air conditioning button to turn the system on when it is off. 205