From google:
Automatic Compass Calibration
This compass is self-calibrating, which eliminates the
need to manually reset the compass. When the vehicle is
new, the compass may appear erratic and the EVIC will
display CAL until the compass is calibrated. You may
also calibrate the compass by completing one or more
360–degree turns (in an area free from large metal or
metallic objects) until the CAL indicator displayed in the
EVIC turns off. The compass will now function normally.
NOTE: A good calibration requires a level surface and
an environment free from large metallic objects such as
buildings, bridges, underground cables, railroad tracks,
etc.
Manual Compass Calibration
If the compass appears erratic and the CAL indicator
does not appear in the EVIC display, you must put the
compass into the Calibration Mode manually, as follows:
1. Turn ON the
ignition switch.
2. Press the UP or DOWN button until the System Setup
(Customer-Programmable Features) menu is reached,
then press the SELECT button.
3. Press the DOWN button until “Calibrate Compass” is
displayed in the EVIC then press and release the SELECT
button.
4. Press and release the SELECT button to start the
calibration. The “CAL” indicator will be displayed in the
EVIC.
5. Complete one or more 360–degree turns (in an area
free from large metal or metallic objects) until the “CAL”
indicator turns off. The compass will now function
normally
