Electrical Compass - Electronic Compass: Diagnosis

Inspection and Verification

Verify the customer concern.
Visually inspect for obvious signs of mechanical or electrical damage. Visual Inspection Chart VISUAL INSPECTION CHART Mechanical Electrical Compass module (integral to the auto-dimming interior mirror) Front Display Interface Module (FDIM) (includes the compass display) Smart Junction Box (SJB) fuse(s): 14 (10A) ( FDIM ) (compass display) 41 (15A) (compass module) Wiring, terminals or connectors
If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
NOTE: Make sure to use the latest scan tool software release. If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).
NOTE: The Vehicle Communication Module (VCM) LED prove-out confirms power and ground from the DLC are provided to the VCM . If the scan tool does not communicate with the VCM : Check the VCM connection to the vehicle. Check the scan tool connection to the VCM . Refer to «MODULE COMMUNICATIONS NETWORK»(ref-372772) , No Power To The Scan Tool, to diagnose no power to the scan tool.
If the scan tool does not communicate with the vehicle: Verify the ignition key is in the ON position. Verify the scan tool operation with a known good vehicle. Refer to «MODULE COMMUNICATIONS NETWORK»(ref-372772) to diagnose no response from the PCM.
Carry out the network test. If the scan tool responds with no communication for one or more modules, Refer to «MODULE COMMUNICATIONS NETWORK»(ref-372772) . If the network test passes, retrieve and record the continuous memory DTCs.
Clear the continuous DTCs and carry out the self-test diagnostics for the FDIM and the Instrument Cluster (IC).
If the DTCs retrieved are related to the concern, go to DTC Charts. For all other DTCs, refer to the Diagnostic Trouble Code (DTC) Chart in «MULTIFUNCTION ELECTRONIC MODULES»(ref-372773) .
If no DTCs related to the concern are retrieved, GO to «SYMPTOM CHART»(ref-372823-S09556148472010093000000) .

DTC Charts

Instrument Cluster (IC) DTC Chart

DTC	Description	Action
B2097	Compass Module Failure	GO to PINPOINT TEST A .
U2013	Compass Module Is Not Responding	GO to PINPOINT TEST A .
All other DTCs		REFER to the Diagnostic Trouble Code (DTC) Chart in MULTIFUNCTION ELECTRONIC MODULES .

INSTRUMENT CLUSTER (IC) DTC CHART

Symptom Chart

Condition	Possible Sources	Action
The compass is inoperative	Fuse Wiring, terminals or connectors Compass module (integral to the auto-dimming interior mirror) Front Display Interface Module (FDIM) (compass display) Instrument Cluster (IC)	GO to PINPOINT TEST A .
The compass is inaccurate	Compass zone setting Compass calibration Compass module (integral to the auto-dimming interior mirror)	GO to PINPOINT TEST B .

SYMPTOM CHART

Pinpoint Test A: The Compass Is Inoperative

Refer to SYSTEM WIRING DIAGRAMS for schematic and connector information.

Note. 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 will result in false resistance readings. Refer to BATTERY, MOUNTING AND CABLES .

Scheme 150

Scheme 150: PINPOINT TEST A: THE COMPASS IS INOPERATIVE

Scheme 151

Scheme 152

Scheme 153

Scheme 154

Scheme 155

A1 CHECK THE COMPASS DISPLAY Ignition ON. Check the compass display. Does the compass display illuminate? Yes: If the compass display illuminates with only 2 bars, GO to A2 . If the compass display turns on, but it does not display all directions, or indicates CAL, GO to «PINPOINT TEST B»(ref-372823-S20370367112010093000000) . No: Refer to «INFORMATION AND ENTERTAINMENT SYSTEMS»(ref-372799) .
A2 CHECK THE POWER CIRCUIT FOR VOLTAGE Ignition OFF. Disconnect: Auto-Dimming Interior Mirror C911 (Without the SYNC System) or C9012 (With the SYNC System). Ignition ON. Measure the voltage between the auto-dimming interior mirror C911-1 (without the SYNC system) or C9012-1 (with the SYNC system), circuit CBP41 (BU), harness side and ground. Is the voltage greater than 10 volts? Yes: GO to A3 . No: VERIFY the SJB fuse 41 (15A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the «SYSTEM WIRING DIAGRAMS»(ref-360982) to identify the possible causes of the circuit short. TEST the system for normal operation.
A3 CHECK THE GROUND CIRCUIT FOR AN OPEN Ignition OFF. Disconnect: Negative Battery Cable. Measure the resistance between the auto-dimming interior mirror C911-3 (without the SYNC system) or C9012-10 (with the SYNC system), circuit GD133 (BK), harness side and ground. Is the resistance less than 5 ohms? Yes: GO to A4 . No: REPAIR the circuit. CONNECT the negative battery cable. TEST the system for normal operation.
A4 CHECK THE COMPASS COMMUNICATION (+) CIRCUIT FOR AN OPEN OR SHORT TO GROUND Connect: Negative Battery Cable. Disconnect: Auto-Dimming Interior Mirror C911 (Without the SYNC System) or C9012 (With the SYNC System). Disconnect: IC C220. For vehicles without the SYNC system, measure the resistance between the auto-dimming interior mirror C911-6, circuit VMC31 (GY/BU), harness side and the IC C220-16, circuit VMC31 (GY/BU), harness side; and between the auto-dimming interior mirror C911-6, harness side and ground. For vehicles with the SYNC system, measure the resistance between the auto-dimming interior mirror C9012-6, circuit VMC31 (GY/BU), harness side and the IC C220-16, circuit VMC31 (GY/BU), harness side; and between the auto-dimming interior mirror C9012-6, circuit VMC31 (GY/BU), harness side and ground. Is the resistance less than 5 ohms between the auto-dimming interior mirror and the IC, and greater than 10,000 ohms between the auto-dimming interior mirror and ground? Yes: GO to A5 . No: REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
A5 CHECK THE COMPASS COMMUNICATION (-) CIRCUIT FOR AN OPEN OR SHORT TO GROUND For vehicles without the SYNC system, measure the resistance between the auto-dimming interior mirror C911-7, circuit VMC30 (BU/GY), harness side and the IC C220-17, circuit VMC30 (BU/GY), harness side; and between the auto-dimming interior mirror C911-7, circuit VMC30 (BU/GY), harness side and ground. For vehicles with the SYNC system, measure the resistance between the auto-dimming interior mirror C9012-2, circuit VMC30 (BU/GY), harness side and the IC C220-17, circuit VMC30 (BU/GY), harness side; and between the auto-dimming interior mirror C9012-2, circuit VMC30 (BU/GY), harness side and ground. Is the resistance less than 5 ohms between the auto-dimming interior mirror and the IC, and greater than 10,000 ohms between the auto-dimming interior mirror and ground? Yes: GO to A6 . No: REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
A6 CHECK FOR DTC U2013 Connect: IC C220. Connect: Auto-Dimming Interior Mirror C911 (Without the SYNC System) or C9012 (With the SYNC System). Ignition ON. Clear the IC DTCs. Ignition OFF. Ignition ON. Wait 10 seconds. Retrieve the IC DTCs. Is DTC U2013 present? Yes: INSTALL a new compass module (integral to the auto-dimming interior mirror). REFER to Auto-Dimming Interior Mirror in «REAR VIEW MIRRORS»(ref-372791) . ADJUST the zone setting. REFER to «COMPASS ZONE ADJUSTMENT»(ref-372823-S30493260812010093000000) . CALIBRATE the compass. REFER to «COMPASS CALIBRATION»(ref-372823-S38733602102010093000000) . TEST the system for normal operation. No: GO to A7 .
A7 CHECK FOR CORRECT IC OPERATION Disconnect the IC connector. Check for: corrosion damaged pins pushed-out pins Connect the IC 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 IC . Refer to «INSTRUMENTATION, MESSAGE CENTER, AND WARNING CHIMES»(ref-372777) . CLEAR the DTCs. REPEAT the self-test. 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.

PINPOINT TEST B: THE COMPASS IS INACCURATE