Ford 2006 Expedition Owner's Manual page 533

Usually, when something affects the compass readings, the compass will
correct itself after a few days of operating your vehicle in normal
conditions. If the compass still appears to be inaccurate, a manual
calibration may be necessary. Refer to Compass calibration adjustment
in this section.
Most geographic areas (zones) have a magnetic north compass point that
varies slightly from the northerly direction on maps. This variation is four
degrees between adjacent zones and will become noticeable as the
vehicle crosses multiple zones. A correct zone setting will eliminate this
error. Refer to Compass zone adjustment in this section.
Compass zone adjustment
1. Determine which magnetic zone
you are in for your geographic
location by referring to the zone
map.
2. Turn ignition to the ON position.
3. Start the engine.
4. Locate the reset button on the
compass sensor mounted on the
base of mirror.
5. Press and hold for six seconds
and release. You will see that ZONE
appears in the instrument cluster
display.
6. Press and release the button until the desired zone number appears.
Note: The range of zone values are from 01 to 15 and "wraps" back to
01.
7. The zone will be stored, and the cluster display will return to the
normal mode when the button has not been pressed for 4 seconds.
Compass calibration adjustment
Perform this adjustment in an open area free from steel structures and
high voltage lines. For optimum calibration, turn off all electrical
accessories (heater/air conditioning, wipers, etc.) and make sure all
vehicle doors are shut.
2006 Expedition (exd)
Owners Guide (post-2002-fmt)
USA (fus)
Driver Controls
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