Compass Variance - Chevrolet 2006 Corvette Owner's Manual

Compass Variance

Compass variance is the difference between earth's
magnetic north and true geographic north. If the mirror
is not adjusted for compass variance, your 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 zone eight.
Under certain circumstances, such as a long distance,
cross-country trip, it will be necessary to adjust the
compass variance.
To adjust for compass variance, do the following:
1. Find your current location and variance zone
number on the zone map that follows.
2-40
2. Press and hold the map light button until a zone
number appears on the display.
3. Once the zone number appears on the display, press
the on/off button quickly until you reach the correct
zone number. Stop pressing the button and the
mirror will return to normal operation. If C appears
in the compass window, the compass may need
calibration. See "Compass Calibration" listed
previously.