Electrical Compass - Electronic Compass: Overview Ford Mustang V рестайлинг

Principles of Operation

Note. The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).

Note. This procedure is only applicable to vehicles without navigation. For vehicles with navigation, refer to DRIVER INFORMATION SYSTEM & ENTERTAINMENT SYSTEM article.

The compass display (located in the Front Display Interface Module (FDIM)) receives battery voltage from the SJB . The compass module (integral to the auto-dimming interior mirror) provides hardwired vehicle directional inputs to the Instrument Panel Cluster (IPC), which sends the compass information to the FDIM over the Medium Speed Controller Area Network (MS-CAN). The compass is capable of self-calibrating. This decreases the need to manually set the compass. If the compass is displaying a heading (and not displaying the C or CAL indicator), the compass is in auto-calibration mode. In this mode, the compass automatically calibrates for changes in vehicle magnetics over the life of the vehicle. This auto-calibration mode makes sure the compass heading is always accurate. If the compass displays the C or CAL indicator for an extended period of time (longer than 5 seconds), this indicates the compass has been placed in the manual calibration mode and therefore, requires manual calibration.

Normal Operation

The compass module (integral to the auto-dimming interior mirror) provides vehicle directional inputs to the Instrument Panel Cluster (IPC), which sends the compass information to the Front Display Interface Module (FDIM) 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 .

1. DTC U0161: 87 (Lost Communication With Compass Module: Missing Message) - sets when the IPC does not receive any communications from the compass module.
2. DTC U0161: 92 (Lost Communication With Compass Module: Performance or Incorrect Operation) - sets when the IPC attempts a self-test of the compass module and its associated circuits and a failure results.

This pinpoint test is intended to diagnose the following

1. Fuse(s)
2. Wiring, terminals or connectors
3. Compass module (integral to the auto-dimming interior mirror)
4. FDIM
5. IPC

When calibrated correctly, the compass module (integral to the auto-dimming interior mirror) provides vehicle directional inputs to the Instrument Panel Cluster (IPC) which sends the compass information to the FDIM over the Medium Speed Controller Area Network (MS-CAN). The FDIM displays the vehicle heading based on the selected zone setting.

This pinpoint test is intended to diagnose the following

1. Compass zone setting
2. Compass calibration
3. Compass module (integral to the auto-dimming interior mirror)