Cadillac 2008 DTS - Manual (Page 111)

Compass Variance
The mirror is set to zone eight upon leaving the factory.
It will be necessary to adjust the compass to compensate
for compass variance if the vehicle is driven outside zone
eight. Under certain circumstances, such as a long
distance, cross-country trip, it will be necessary to
adjust the compass variance.
Compass variance is the difference between earth’s
magnetic north and true geographic north. If the mirror
is not adjusted to account for zone changes, the
compass could give false readings.
To adjust for zone changes, do the following:
1. Find your current location and variance zone
number on the zone map that follows.
2. Press and hold the “auto highbeam” button
approximately six seconds until a zone number
appears in the display.
3. Once the zone number appears in the display,
press the “auto highbeam” 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 needs calibration. See “Compass
Calibration” listed previously.
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