Pinpoint Tests AQ: The Compass Is Inoperative (Without Navigation)
Instrumentation, Message Center and Warning Chimes
Pinpoint Tests
Pinpoint Test AQ: The Compass Is Inoperative (Without Navigation)
Refer to Wiring Diagram Set 60, Instrument Cluster for schematic and connector information. Diagrams By Number
Normal Operation
The Instrument Panel Cluster (IPC) receives the compass display message from the Body Control Module (BCM) over the High Speed Controller Area Network (HS-CAN) communication bus. The BCM receives the compass display message from the auto-dimming interior mirror over the Local Interconnect Network (LIN) communication bus. The BCM is only a gateway for the compass information and does not control the compass display. The auto-dimming interior mirror receives voltage from the BCM fuse 32 (15A).
If the compass display message is missing or invalid for 5 seconds or less, the compass displays the last vehicle direction based upon the last known good compass display message received. If the compass display message is invalid or missing for 5 seconds or more, the IPC defaults the display to all dashes (---).
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Auto-dimming interior mirror
- BCM
PINPOINT TEST AQ: THE COMPASS IS INOPERATIVE (WITHOUT NAVIGATION)
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: Failure to disconnect the battery when instructed results in false resistance readings. Refer to Battery, Mounting and Cables Battery Disconnect / Connect.
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AQ1 CHECK THE AUTO-DIMMING INTERIOR MIRROR VOLTAGE SUPPLY
- Ignition OFF.
- Disconnect: Auto-Dimming Interior Mirror C911.
- Ignition ON.
- Measure the voltage between the auto-dimming interior mirror C911-1, circuit CBP32 (GN/VT), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to AQ2.
No
VERIFY the BCM 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. Diagrams By Number
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AQ2 CHECK THE COMPASS MODULE GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable .
- Measure the resistance between the auto-dimming interior mirror C911-4, circuit GD133 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to AQ3.
No
REPAIR circuit GD133 (BK) for an open. CLEAR the DTCs. REPEAT the self-test.
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AQ3 CHECK THE COMPASS COMMUNICATION BUS FOR A SHORT TO VOLTAGE
- Connect: Negative Battery Cable .
- Disconnect: DC/AC Inverter Module C3501a.
- Disconnect: BCM C2280b.
- Ignition ON.
- Measure the voltage between the auto-dimming interior mirror C911-2, circuit VDM01 (BU/WH), harness side and ground.
- Is any voltage present?
Yes
REPAIR circuit VDM01 (BU/WH) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to AQ4.
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AQ4 CHECK THE COMPASS COMMUNICATION BUS FOR AN OPEN AND SHORT TO GROUND
- Disconnect: BCM C2280b.
- Measure the resistance between the BCM C2280b-52, circuit VDN01 (BU/WH), harness side and the auto-dimming interior mirror C911-2, circuit VDM01 (BU/WH), harness side; and between the BCM C2280b-52, circuit VDN01 (BU/WH), and ground.
- Is the resistance less than 5 ohms between the BCM and the auto-dimming interior mirror, and greater than 10,000 ohms between the BCM and ground?
Yes
INSTALL a new auto-dimming interior mirror. REFER to 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. CLEAR the DTCs. REPEAT the self-test. If the compass is still inoperative, GO to AQ5.
No
REPAIR circuit VDM01 (BU/WH) for an open or short to ground. CLEAR the DTCs. REPEAT the self-test.
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AQ5 CHECK FOR CORRECT BCM OPERATION
- Disconnect all the BCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the BCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new BCM. REFER to Multifunction Electronic Modules Service and Repair. 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.
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