Cadillac 2008 STS, Owner'S Manual, Page: 114 / 500

Compass Variance
The zone is set to 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, as during
a long distance cross-country trip, it will be necessary to
adjust for compass variance. Compass variance is
the difference between earth’s magnetic north and true
geographic north. If not adjusted to account for
compass variance, your compass could give false
readings.
To adjust for compass variance do the following:
1. Find the current location and variance zone number
on the following zone map.
2. Press and hold the on/off button until a zone
number appears in the display.
3. Once the zone number appears in the display,
press the on/off button quickly until the correct
zone number appears in the display. 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.
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