Electrical Compass - Electronic Compass: Diagnosis — Electrical Compass - Electronic Compass — Communication Devices

Inspection and Verification

Verify the customer concern.
Visually inspect for obvious signs of mechanical or electrical damage. VISUAL INSPECTION CHART Mechanical Electrical Compass module (integral to the auto-dimming interior mirror) Front Display Interface Module (FDIM) Smart Junction Box (SJB) fuse (s): 14 (10A) ( FDIM ) 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.
If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).
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-376006) , 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 is in the ON position. Verify the scan tool operation with a known good vehicle. Refer to «MODULE COMMUNICATIONS NETWORK»(ref-376006) 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-376006) . 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 Panel Cluster (IPC).
If the DTCs retrieved are related to the concern, go to «DTCS CHARTS»(ref-376055-S15660605952010103100000) . For all other DTCs, refer to the Diagnostic Trouble Code (DTC) Chart in «MULTIFUNCTION ELECTRONIC MODULES»(ref-376007) .
If no DTCs related to the concern are retrieved, GO to «SYMPTOM CHART»(ref-376055-S35239310492010103100000) .

DTC Charts

Note. Refer to Description and Operation, Intelligent Access (IA) with Push Button Start in ANTI-THEFT - PASSIVE ANTI-THEFT SYSTEM (PATS) to review the procedures for achieving the various ignition states (ignition in accessory, ignition on, ignition start, ignition off) on vehicles with this feature.

Note. This module utilizes a 5-character DTC followed by a 2-character failure-type code. The failure-type code provides information about specific fault conditions such as opens, or shorts to ground. Continuous memory DTCs have an additional 2-character DTC status code suffix to assist in determining DTC history.

DTC	Description	Action
U0161:00	Lost Communication With Compass Module: No Sub Type Information	GO to PINPOINT TEST A .
U0462:68	Invalid Data Received From Compass Module: Event Information	GO to PINPOINT TEST A .
All other DTCs		REFER to the Diagnostic Trouble Code (DTC) Chart in MULTIFUNCTION ELECTRONIC MODULES .

INSTRUMENT PANEL CLUSTER (IPC) DTC CHART

Symptom Chart

Condition	Possible Sources	Action
The compass is inoperative	Fuse(s) Wiring, terminals or connectors Compass module (integral to the auto-dimming interior mirror) Front Display Interface Module (FDIM) (compass display) Instrument Panel Cluster (IPC)	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. After installing a new compass module, always set the zone and calibrate the compass.

Note. Failure to disconnect the battery when instructed will result in false resistance readings. Refer to BATTERY, MOUNTING AND CABLES .

Scheme 158

Scheme 158: PINPOINT TEST A: THE COMPASS IS INOPERATIVE

Scheme 159

Scheme 160

Scheme 161

Scheme 162

A1 CHECK THE COMPASS DISPLAY Ignition ON. Check the compass display in the lower left corner of the FDIM . 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-376055-S04573636682010103100000) . No: REFER to «INFORMATION AND ENTERTAINMENT SYSTEMS»(ref-376027) .
A2 CHECK THE POWER CIRCUIT FOR VOLTAGE Ignition OFF. Disconnect: Auto-Dimming Interior Mirror C911. Ignition ON. Measure the voltage between the auto-dimming interior mirror C911-1, 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. TEST the system for normal operation. If not OK, REFER to the «SYSTEM WIRING DIAGRAMS»(ref-360993) to identify the possible causes of the circuit short.
A3 CHECK THE GROUND CIRCUIT FOR AN OPEN Ignition OFF. Disconnect: Negative Battery Cable. Measure the resistance between the auto-dimming interior mirror C911-10, circuit GD133 (BK), harness side and ground. Is the resistance less than 5 ohms? Yes: GO to A4 . No: REPAIR the circuit. TEST the system for normal operation.
A4 CHECK THE DTCs Connect: Negative Battery Cable. Connect: Auto-Dimming Interior Mirror C911. Ignition ON. Clear the FDIM DTCs. Ignition OFF. Ignition ON. Wait 10 seconds. Retrieve the FDIM DTCs. Is DTC U0155 present? Yes: REFER to «INFORMATION AND ENTERTAINMENT SYSTEMS»(ref-376027) . No: GO to A5 .
A5 CHECK THE COMPASS COMMUNICATION (+) CIRCUIT FOR AN OPEN OR SHORT TO GROUND Ignition OFF. Disconnect: Auto-Dimming Interior Mirror C911. Disconnect: IPC C220. Measure the resistance between the auto-dimming interior mirror C911-6, circuit VMC31 (GY/BU), harness side and the IPC C220- 24, circuit VMC31 (GY/BU), harness side; and between the auto-dimming interior mirror C911-6, circuit VMC31 (GY/BU), harness side and ground. Is the resistance less than 5 ohms between the auto-dimming interior mirror and the IPC , 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 THE COMPASS COMMUNICATION (-) CIRCUIT FOR AN OPEN OR SHORT TO GROUND Measure the resistance between the auto-dimming interior mirror C911-2, circuit VMC30 (BU/GY), harness side and the IPC C220- 23, circuit VMC30 (BU/GY), harness side; and between the auto-dimming interior mirror C911-2, circuit VMC30 (BU/GY), harness side and ground. Is the resistance less than 5 ohms between the auto-dimming interior mirror and the IPC , and greater than 10,000 ohms between the auto-dimming interior mirror and ground? Yes: GO to A7 . No: REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
A7 CHECK THE COMPASS COMMUNICATION CIRCUITS FOR A SHORT TO VOLTAGE Ignition ON. Measure the voltage between the auto-dimming interior mirror C911-2, circuit VMC30 (BU/GY), harness side and ground; and between the auto-dimming interior mirror C911-6, circuit VMC31 (GY/BU), harness side and ground. Is any voltage present? Yes: REPAIR the circuit in question. TEST the system for normal operation. No: GO to A8 .
A8 CHECK FOR DTC U0161:00 Connect: IPC C220. Connect: Auto-Dimming Interior Mirror C911. Ignition ON. Clear the IPC DTCs. Ignition OFF. Ignition ON. Wait 10 seconds. Retrieve the IPC DTCs. Is DTC U0161:00 present? Yes: INSTALL a new auto-dimming interior mirror. REFER to «REAR VIEW MIRRORS»(ref-376061) . ADJUST the zone setting. REFER to «COMPASS ZONE ADJUSTMENT»(ref-376055-S05917228472010103100000) . CALIBRATE the compass. REFER to «COMPASS CALIBRATION»(ref-376055-S25312616752010103100000) . TEST the system for normal operation. No: GO to A9 .
A9 CHECK FOR CORRECT IPC OPERATION Disconnect the IPC connector. Check for: corrosion damaged pins pushed-out pins Connect the IPC 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 . REFER to «INSTRUMENTATION, MESSAGE CENTER, AND WARNING CHIMES»(ref-376011) . 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. CLEAR the DTCs. REPEAT the self-test.

Pinpoint Test B: The Compass Is Inaccurate

Note. This procedure is only applicable to vehicles without navigation. For vehicles with navigation, refer to INFORMATION AND ENTERTAINMENT SYSTEMS .