Your vehicle may have an automatic-dimming rearview mirror with a compass and temperature display.
When turned on, this mirror automatically dims to the proper level to minimize glare from headlamps behind you after dark.
The mirror has an eight-point compass and temperature display in the upper right corner of the mirror face. The display shows the current outside temperature and the vehicle's current direction.
Mirror Operation
The automatic dimming feature is turned on or off by briefly pressing the COMP button located on the bottom of the mirror face. A light on the mirror will be lit while the feature is turned on. It will go out while the feature is turned off.
Temperature Display
The TEMP button located on the bottom of the mirror face changes the temperature display. You can select °F, °C, or turn the display off.
Compass Variance
Press the COMP button once briefly to turn the compass on or off. When on, the display will show the compass direction, with a maximum of two characters. For example, NE is displayed for north-east.
Compass Calibration
Press and hold the COMP button down for six seconds to activate the compass calibration mode. If your vehicle has the optional mirror with the compass, temperature display and OnStar system, press the on/off button for nine seconds.
CAL will be displayed in the compass/temperature window on the mirror.
The mirror can be calibrated in one of two ways:
| • | Drive the vehicle in circles at 5 mph (8 km/h) or less until CAL is no longer displayed in the compass window. |
| • | Drive the vehicle on your everyday routine. (This method may take longer to calibrate). |
Compass Variation
Compass variance is the difference between earth's magnetic north and true geographic north. If not adjusted to account for compass variance, your compass could give false readings. The mirror is set to zone eight upon leaving the factory. It will be necessary to adjust the compass to compensate for compass variance if you live outside zone eight. Under certain circumstances, such as during a long distance cross-country trip, it will be necessary to adjust for compass variance.
To adjust for compass variance, do the following:
- Find your current location and variance zone number on the map.
- Press and hold the COMP button for three seconds. If your vehicle has the optional mirror with the compass, temperature display and OnStar® system, press the on/off button for six seconds. Release the button when ZONE is displayed. The number shown is the current zone number.
- Scroll through the zone numbers that appear in the compass/temperature window on the mirror by pressing the COMP button or the on/off button. Once you find your zone number, release the button. After about four seconds, the mirror will return to the compass and temperature display, and the new zone number will be set.
