Pontiac Grand Prix 2007 Owner's Manual page 203

To adjust for compass variance, use the following
procedure:
1. Find the vehicle's current location and
variance zone number on the map.
2. Press the set/reset button to scroll through
and select the appropriate variance zone.
3. Press the options button to advance to the
calibration screen.
4. Drive the vehicle in a circle two times to
activate the compass.
The direction the vehicle is moving will be
displayed in the bottom left corner of the screen,
and will appear in the gages, fuel, trip, and
some of the options modes.
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