1998 Ford Expedition gps

Yes it can be calibrated. Here is what to do:

1) start the car

2) locate the compass module located on base of mirror

3) insere a paperclip into the switch access hole under the compass module

4) press the switch for 2 or 4 seconds until the "CAL" and direction are displayed

5) release switch (paper clip)

6) slowly drive the vehicle in circles (less than 3MPH) until the "CAL" indicator turns off. It will take between 3 to 5 circles to complete.

7) The compass is now calibrated.

Let me know if this helps.

Joe