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Pinpoint Test CA: The Compass Is Inoperative




Instrumentation, Message Center and Warning Chimes

Pinpoint Test CA: The Compass Is Inoperative

Refer to Wiring Diagram Set 124, Power Mirrors for schematic and connector information. [1][2]Diagrams By Number

NOTE: This procedure is only applicable to vehicles without navigation. For vehicles with navigation, refer to Accessories and Optional Equipment.

Normal Operation

The compass module (integral to the auto-dimming interior mirror) provides vehicle directional inputs over the compass communication circuits to the Instrument Panel Cluster (IPC) , which sends the compass information to the FDIM (Front Display Interface Module) over the Medium Speed Controller Area Network (MS-CAN). The FDIM (Front Display Interface Module) displays the compass direction according to the information that has been provided by the compass module to the IPC (Instrument Panel Cluster).

- DTC U0161:00 (Lost Communication With Compass Module: No Sub Type Information)- sets when the IPC (Instrument Panel Cluster) does not receive any communication from the compass module for 5 seconds or longer.

- DTC U0462:68 (Invalid Data Received From Compass Module: Event Information)- sets when the IPC (Instrument Panel Cluster) 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:

- Fuse(s)

- Wiring, terminals or connectors

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

- FDIM (Front Display Interface Module) (compass display)

- IPC (Instrument Panel Cluster)

PINPOINT TEST CA : THE COMPASS IS INOPERATIVE

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 module.

CA1 CHECK THE AUTO-DIMMING INTERIOR MIRROR VOLTAGE SUPPLY

- Ignition OFF.

- Disconnect: Auto-Dimming Interior Mirror C911 or C9039 (Camera Display Mirror).

- Ignition ON.

- Measure the voltage between the auto-dimming interior mirror C911-1 or C9039-1 (camera display mirror), circuit CBP41 (BU), harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to CA2.

No
VERIFY the BCM (Body Control Module) fuse 32 (15A). If OK, REPAIR circuit CBP32 (GN/VT) for an open. TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. [1][2]Diagrams By Number

CA2 CHECK THE COMPASS MODULE GROUND CIRCUIT FOR AN OPEN

- If not equipped with a camera display mirror, measure the voltage between the auto-dimming interior mirror C911-1, circuit CBP41 (BU), harness side and auto-dimming interior mirror C911-4, circuit GD139 (BK/YE), harness side and ground.





- If equipped with a camera display mirror, measure the voltage between the auto-dimming interior mirror C9039-1, circuit CBP41 (BU), harness side and auto-dimming interior mirror C9039-3, circuit GD139 (BK/YE), harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to CA3.

No
REPAIR circuit GD133 (BK) for an open. CLEAR the DTCs. REPEAT the self-test.

CA3 CHECK THE COMPASS COMMUNICATION CIRCUITS FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: IPC (Instrument Panel Cluster) C220.

- Ignition ON.

- Measure the voltage between the auto-dimming interior mirror C911-9 or C9039-9 (camera display mirror), circuit VMC31 (GY/BU), harness side and ground; and between the auto-dimming interior mirror C911-10 or C9039-10 (camera display mirror), circuit VMC30 (BU/GY), harness side and ground.





Is any voltage present?

Yes
REPAIR the circuit in question for a short to voltage. CLEAR the DTCs. REPEAT the self-test.

No
GO to CA4.

CA4 CHECK THE COMPASS COMMUNICATION PLUS (+) CIRCUIT FOR AN OPEN AND SHORT TO GROUND

- Ignition OFF.

- Measure the resistance between the IPC (Instrument Panel Cluster) C220-23, circuit VMC30 (BU/GY), harness side and the auto-dimming interior mirror C911-10 or C9039-10 (camera display mirror), VMC30 (BU/GY), harness side; and between the IPC (Instrument Panel Cluster) C220-23, circuit VMC30 (BU/GY), harness side and ground.





Is the resistance less than 5 ohms between the IPC (Instrument Panel Cluster) and the auto-dimming interior mirror, and greater than 10,000 ohms between the IPC (Instrument Panel Cluster) and ground?

Yes
GO to CA5.

No
REPAIR the circuit for an open or short to ground. CLEAR the DTCs. REPEAT the self-test.

CA5 CHECK THE COMPASS COMMUNICATION MINUS (-) CIRCUIT FOR AN OPEN AND SHORT TO GROUND

- Ignition OFF.

- Measure the resistance between the IPC (Instrument Panel Cluster) C220-24, circuit VMC31 (GY/BU), harness side and the auto-dimming interior mirror C911-9 or C9039-9 (camera display mirror), VMC31 (GY/BU), harness side; and between the IPC (Instrument Panel Cluster) C220-24, circuit VMC31 (GY/BU), harness side and ground.





Is the resistance less than 5 ohms between the IPC (Instrument Panel Cluster) and the auto-dimming interior mirror, and greater than 10,000 ohms between the IPC (Instrument Panel Cluster) and ground?

Yes
GO to CA6.

No
REPAIR the circuit for an open or short to ground. CLEAR the DTCs. REPEAT the self-test.

CA6 CHECK FOR CORRECT IPC (Instrument Panel Cluster) OPERATION

- Disconnect the IPC (Instrument Panel Cluster) connector.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect the IPC (Instrument Panel Cluster) connector and make sure it seats correctly.

- Operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new IPC (Instrument Panel Cluster). REFER to Instrument Panel Cluster (IPC) . TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.