2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 249

2. Set the driver's and passenger's temperature. To find your comfort setting, start with a 23°C (74°F) temperature setting and allow about 20 minutes for the system to regulate. Use the driver or passenger temperature buttons to adjust the temperature setting as necessary. If a temperature setting of 15°C (60°F) is chosen, the system remains at the maximum cooling setting. If a temperature setting of 32°C (90°F) is chosen, 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. 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 the fan on until warm air is available. The length of delay depends on the engine coolant temperature. Pressing the fan switch overrides this delay and changes the fan to a selected speed. Manual Operation D C (Fan Control): Press these buttons to increase or decrease the fan speed. Pressing either fan button while in automatic control places the fan under manual control. The fan setting remains displayed and the AUTO light turns off. The air delivery mode remains under automatic control. H G (Air Delivery Mode Control): Press these buttons to change the direction of the airflow in the vehicle. Repeatedly press either button until the desired mode appears on the display. Pressing either mode button while the system is off changes the air delivery mode without turning the system on. Pressing either mode button while in automatic control places the mode under manual control. The air delivery mode setting is displayed and the AUTO light turns off. The fan remains under automatic control. H (Vent): Air is directed to the instrument panel outlets. ) (Bi-Level): Air is divided between the instrument panel and floor outlets. Some air is directed towards the windshield and side window outlets. 4-25