2003 Buick Regal Owner's Manual - Page 127

Automatic Operation AUTO (Automatic): Press the AUTO button for automatic control of the inside temperature, the air delivery mode and the fan speed. You may notice a delay of two to three minutes before the fan comes on when the automatic operation is used in cold weather. For the automatic system to function, the temperature must be set between 61"F (16°C) and 89°F (31"C). In cold weather, the system will start at reduced fan speeds to avoid blowing cold air into your vehicle until warmer air is available. The system will start out blowing air at the floor but may change modes automatically as the vehicle warms up to maintain the chosen temperature setting. The length of time needed for warm up will depend on the outside temperature and the length of time that has elapsed since your vehicle was last driven. 3. Wait for the system to regulate. This may take from 10 to 30 minutes. Then, adjust the temperature, if necessary. 1. Adjust the temperature to a comfortable setting. 2. Press the AUTO button. Choosing the coldest or warmest temperature setting will not cause the system to heat or cool any faster. If you set the system at the warmest temperature setting, 90°F (32"C), hot air will be directed to the floor, the fan will increase to the highest speed, and, the system will remain in manual mode at that temperature. The system will not return to automatic until the temperature setting is lowered. If you set the system at the coldest temperature setting, 60°F (15"C), cold interior air will be recirculated through the air panel outlets, and the fan will increase to the highest speed. The system will not return to automatic until the temperature is raised. 3-22 Do not cover the solar sensor located in the center of the instrument panel, near the windshield. For more information on the solar sensor, see "Solar Sensor" later in this section. Manual Operation During daylight hours, you may want to adjust the instrument panel brightness control to the highest setting in order to see the indicator lights that go on for the various climate control settings. OFF: Pressing the OFF button cancels automatic operation and places the system in manual mode. Press the AUTO button to return to automatic operation.