2004 Chevrolet Monte Carlo Owner's Manual - Page 167

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. VAR will be displayed. Press the MODE button until the proper variance zone number on the map is shown. Press the RESET button to set the new variance zone and resume normal operation. All the display segments will be illuminated briefly to acknowledge the change in zone number. A chime will sound to confirm that the new zone number has been set. Setting the Variance 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 CAL will be displayed, and all segments of the compass will be illuminated where the compass reading is normally displayed. Turn the ignition on and cycle the DIC to the Compass/ Temperature mode. Press the RESET button for about five seconds. The last entered variance zone number and To calibrate the compass, in an area free from large metal objects, make one to two 360° turns. The calibration symbol will turn off and the compass reading will be displayed. 3-53