2003 Pontiac Montana Owner's Manual - Page 234
2003 Pontiac Montana Manual
Page 234 highlights
Compass Variance Compass variance is the difference between magnetic north and geographic north. In some areas of the country, the difference is great enough to cause the compass to give false readings. If this occurs, the compass variance must be set. Setting the Variance Turn the ignition on and cycle the DIC to the compass/temperature mode. Press both the E/M and MODE buttons simultaneously for approximately five seconds. The last entered variance zone number will be displayed. Press the E/M button until the proper variance number, as shown on the map, is showing. Press the MODE button to set the new variance zone and resume normal operation. The display will show all the display segments briefly to acknowledge the change in the zone number. Automatic Compass Calibration The compass is self-calibrating, which eliminates the need to manually set the compass. When the vehicle is new, the calibration process may not be complete. In these cases the calibration symbol C will be displayed where the compass reading is normally displayed. To calibrate the compass, in an area free from large metal objects, make three 360" turns. The calibration symbol will turn off and the compass reading will be displayed. 3-57