Test D: The Compass Is Inaccurate

PINPOINT TEST D: THE COMPASS IS INACCURATE

D1-D3:

Normal Operation
The compass sensor module communicates the vehicle direction to the instrument cluster through the compass communication data plus circuit VMC31 (YE/GN) and compass communication data minus circuit VMC30 (BU/GY). The magnetic fields generated by the earths north and south poles are divided into zones that differ from each other with respect to how the magnetic fields appear. The magnetic north can change by up to 4 degrees between zones and become noticeable across multiple zones. The compass zone must be set to the correct zone for the compass to read accurately. Factors within the vehicle may affect the ability of the compass module to accurately read the magnetic north. Calibrating the compass allows the compass module to compensate for vehicle factors that influence the accuracy of the compass.

NOTE: Outside factors such as bridges, steel structures, tall buildings and power lines also affect compass accuracy.

Possible Causes
- Vehicle magnetization
- Zone setting
- Calibration
- Compass module