Pinpoint Test B: The Compass Is Inaccurate

Electronic Compass

Pinpoint Test B: The Compass Is Inaccurate

NOTE: This procedure is only applicable to vehicles without navigation. For vehicles with navigation, there is no compass zone adjustment.

Normal Operation

The compass module (integral to the auto-dimming interior mirror) provides vehicle directional inputs over the communication circuits to the Instrument Panel Cluster (IPC), which sends the compass information to the Front Display Interface Module (FDIM) (compass display) over the Medium Speed Controller Area Network (MS-CAN). The FDIM displays the compass direction according to the information that has been provided by the compass module to the IPC. The compass display may provide inaccurate readings only if there is a concern with the compass module or the compass zone setting is incorrect or the compass is out of calibration.

This pinpoint test is intended to diagnose the following:

- Compass zone setting
- Compass calibration
- Compass module (integral to the auto-dimming interior mirror)


PINPOINT TEST B: THE COMPASS IS INACCURATE

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

NOTE: Always set the zone and calibrate the compass before replacing an inaccurate compass.

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B1 CHECK THE COMPASS ACCURACY

- Position the vehicle and observe the compass display as follows:





- Does the compass display as indicated?

Yes
The compass is OK. The concern may have been caused by an incorrect zone setting, or the compass was out of calibration.

No
INSTALL a new compass module. REFER to Auto-Dimming Interior Mirror in Rear View Mirrors Interior Rear View Mirror. SET the zone. REFER to Compass Zone Adjustment Compass Zone Adjustment. CALIBRATE the compass. REFER to Compass Calibration Compass Calibration. TEST the system for normal operation.

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