2010 Buick Lucerne Owner's Manual - Page 142

Compass Variance The compass is set to zone eight. If you do not live in zone eight or drive out of the area, the compass variance needs to be changed to the appropriate zone. To adjust for compass variance: 1. Find your current location and variance zone number on the following zone map. 2. Press and hold O until the zone number displays. The number shown is the current zone number. 3. Once the zone number displays, press O repeatedly until the correct zone number displays. Stop pressing the button and the mirror returns to normal operation. If CAL appears in the compass window, the compass may need calibration. See "Compass Calibration" listed previously. 3-34