Mountaineer RWD V6-4.0L (2008)
B3-B4
Test C: The Compass Is Inaccurate
PINPOINT TEST C: THE COMPASS IS INACCURATE
Normal Operation
The compass sensor module communicates the vehicle direction to the instrument cluster (IC) 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.
This pinpoint test is intended to diagnose the following:
-
Calibration
-
Zone setting
-
Vehicle magnetization
-
Compass sensor module
