Jeep 2008 Patriot - Manual (Page 193)

Compass Variance
Compass Variance is the difference between magnetic
North and geographic North. In some areas of the
country, the difference between magnetic and geographic
North is great enough to cause the compass to give false
readings. In order to ensure compass accuracy, the Com-
pass Variance should be set to the zone number on the
Compass Variance map that corresponds to the current
location of the vehicle.
NOTE: Magnetic materials should be kept away from
the Instrument Panel. This is where the compass sensor is
located.
UNDERSTANDING YOUR INSTRUMENT PANEL 191
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