2001 GMC Sierra 1500 Pickup Owner's Manual - Page 148

Electrochromic Mirror Operation The time period you need to press and hold the TEMP button to turn the electrochromic feature on or off is fifteen seconds. The indicator light to the right of the TEMP button will still turn on or off to show you when the electrochromic feature is activated. Compass Operation Press the COMP button once briefly to turn the compass on or off. When the ignition and the compass feature are on, the compass will show two character boxes for approximately two seconds. After two seconds, the mirror will display the compass heading. When cleaning the mirror, use a paper towel or similar material dampened with glass cleaner. Do not spray glass cleaner directly on the mirror as that may cause the liquid cleaner to enter the mirror housing. Compass Calibration The compass may need calibration if: D After five seconds, the display does not show a compass heading ("N" for North, for example), there may be a strong magnetic field interfering with the compass. Such interference may be caused by a magnetic antenna mount, magnetic note pad holder or a similar magnetic item. and the compass zone variance is set correctly. D The compass does not display the correct heading In order to calibrate, "CAL" must be displayed in the mirror compass windows. If "CAL" is not displayed, push in the "COMP" button for approximately eight seconds or until "CAL" is displayed. The compass can be calibrated in one of two ways: D Drive the vehicle in circles at five mph (8 km/h) or less until the display reads a direction, or D Drive the vehicle on your everyday routine and after several turns the compass will become calibrated and will display a direction. 2-65