Automatic Compass Calibration
WARNING: This page is about a different car, the 2003 Chrysler PT Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
The self calibrating feature of the compass eliminates the need to calibrate the compass for normal conditions. After approximately 10 ignition cycles the CAL light will turn ON. The CAL symbol may also appear after the vehicle is subjected to a high level of magnetism. After completing three 360° (degree) circles in an area free from large metal or metallic objects, the CAL symbol will turn off and the compass will function normally.