Jeep 2005 Liberty - Manual (Page 138)

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.
If this occurs, the compass variance must be set according
to the Compass Variance Map.
To set the variance: Turn the ignition ON and set the
display to “Compass/Temperature.” Press and hold the
RESET button five seconds (no more than 10 seconds).
The last variance zone number will be displayed. Press
the STEP button to select the new variance zone and
press the RESET button to resume normal operation.
138 UNDERSTANDING THE FEATURES OF YOUR VEHICLE