2007 Chevrolet Corvette Owner's Manual - Page 111

Automatic Dimming Mirror Operation The automatic dimming mirror function is turned on each time the ignition is started. A light near the on/off button will come on to indicate the automatic dimming is on. Press the on/off button for about six seconds to manually turn the automatic dimming function on or off. 2. Press the button again to change the display to the desired unit of measurement. After approximately four seconds of inactivity, the new unit will be locked in and the compass/temperature display will return. If an abnormal temperature reading is displayed for an extended period of time, please consult your dealer. Under certain circumstances, a delay in updating the temperature is normal. Compass Display Press the on/off button, located to the far left, briefly to turn the compass display on or off. If the display reads CAL, the compass needs to be calibrated. For more information, see "Compass Calibration" later in this section. To adjust between Fahrenheit and Celsius: 1. Press and hold the on/off button for approximately four seconds until either a flashing °F, or °C appears. Compass Variance Compass variance is the difference between earth's magnetic north and true geographic north. If not adjusted to account for compass variance, the mirror's compass could give false readings. The mirror is set in zone eight upon leaving the factory. It will be necessary to adjust the compass to compensate for compass variance if you live outside of zone eight. Under certain circumstances, as during a long distance cross-country trip, it will also be necessary to adjust for compass variance. To adjust for compass variance do the following: 1. Find your current location and variance zone number on the following zone map. 111