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Pinpoint Test W: Intermittent No (MS-CAN) Communication, Communication Can Be Intermittently Established




Communications Network

Pinpoint Test W: Intermittent No Medium Speed Controller Area Network (MS-CAN) Communication, Communication Can Be Intermittently Established

Normal Operation

The Medium Speed Controller Area Network (MS-CAN) uses an unshielded twisted pair cable. In the event that 1 of the 2 network circuits (MS-CAN (Medium Speed Controller Area Network) + or MS-CAN (Medium Speed Controller Area Network) -) becomes open to a module on the network, unreliable network communication to all modules on the network can result.

The following modules communicate with the scan tool using the MS-CAN (Medium Speed Controller Area Network) :

- Audio Front Control Module (ACM)

- Accessory Protocol Interface Module (APIM)

- Audio Digital Signal Processing (DSP) module

- Driver Seat Module (DSM)

- Front Controls Interface Module (FCIM)

- Front Display Interface Module (FDIM)

- Global Positioning System Module (GPSM)

- HVAC module

- Instrument Cluster (IC)

- Liftgate/Trunk Module (LTM)

- Rear Entertainment Module (RETM)

- Smart Junction Box (SJB)

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

PINPOINT TEST W : INTERMITTENT NO MS-CAN (Medium Speed Controller Area Network) COMMUNICATION, COMMUNICATION CAN BE INTERMITTENTLY ESTABLISHED

NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test. Inspection and Verification

NOTE: Various network DTCs set while disabling modules in this test procedure, which need to be cleared after the diagnostic procedure is completed.

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings.

W1 CHECK THE DLC (Data Link Connector) PINS FOR DAMAGE

- Ignition OFF.

- Disconnect the scan tool cable from the Data Link Connector (DLC).

- Inspect DLC (Data Link Connector) pins 3 and 11 for damage.





Are DLC (Data Link Connector) pins 3 and 11 OK?

Yes
GO to W2.

No
REPAIR the DLC (Data Link Connector) as necessary. CLEAR the DTCs. REPEAT the network test with the scan tool.

W2 CHECK THE MS-CAN (Medium Speed Controller Area Network) TERMINATION RESISTANCE

- Disconnect: Negative Battery Cable.

- Measure the resistance between the DLC (Data Link Connector) C251-3, circuit VDB06 (GY/OG), harness side and the DLC (Data Link Connector) C251-11, circuit VDB07 (VT/OG), harness side.





Is the resistance between 54 and 66 ohms?

Yes
GO to W3.

No
GO to Pinpoint Test X. Pinpoint Test X: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding

W3 CHECK THE MS-CAN (Medium Speed Controller Area Network) (+) AND MS-CAN (Medium Speed Controller Area Network) (-) CIRCUITS FOR A SHORT TO GROUND

- Measure the resistance between the DLC (Data Link Connector) C251-3, circuit VDB06 (GY/OG), harness side and ground; and between the DLC (Data Link Connector) C251-11, circuit VDB07 (VT/OG), harness side and ground.





Are the resistances greater than 1,000 ohms?

Yes
GO to W4.

No
GO to Pinpoint Test X. Pinpoint Test X: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding

W4 CHECK THE MS-CAN (Medium Speed Controller Area Network) (+) AND MS-CAN (Medium Speed Controller Area Network) (-) CIRCUITS FOR A SHORT TO VOLTAGE

- Connect: Negative Battery Cable.

- Ignition ON.

- Measure the voltage between the DLC (Data Link Connector) C251-3, circuit VDB06 (GY/OG), harness side and ground; and between the DLC (Data Link Connector) C251-11, circuit VDB07 (VT/OG), harness side and ground.





Is the voltage greater than 6 volts?

Yes
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.

No
GO to W5.

W5 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE SJB (Smart Junction Box) DISABLED

- Disconnect: Smart Junction Box (SJB) Fuse 5 (10A).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test.

Do all other MS-CAN (Medium Speed Controller Area Network) modules pass the network test?

Yes
INSTALL the removed fuse. GO to Pinpoint Test R. Pinpoint Test R: The Smart Junction Box (SJB) Does Not Respond To The Scan Tool

No
INSTALL the removed fuse. GO to W6.

W6 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE ACM (Audio Front Control Module) DISABLED

- Disconnect: SJB (Smart Junction Box) Fuse 39 (20A).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test.

Do all other MS-CAN (Medium Speed Controller Area Network) modules pass the network test?

Yes
INSTALL the removed fuse. GO to Pinpoint Test K. Pinpoint Test K: The Audio Front Control Module (ACM) Does Not Respond To The Scan Tool

No
INSTALL the removed fuse. If the vehicle is equipped with an audio DSP (Digital Signal Processing) module, GO to W7.

If the vehicle is not equipped with an audio DSP (Digital Signal Processing) module, GO to W8.

W7 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE AUDIO DSP (Digital Signal Processing) MODULE DISABLED

- Disconnect: Battery Junction Box (BJB) Fuse 7 (30A).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test.

Do all other MS-CAN (Medium Speed Controller Area Network) modules pass the network test?

Yes
INSTALL the removed fuse. GO to Pinpoint Test L. Pinpoint Test L: The Audio Digital Signal Processing (DSP) Module Does Not Respond To The Scan Tool

No
INSTALL the removed fuse. GO to W8.

W8 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE APIM (Accessory Protocol Interface Module), FDIM (Front Display Interface Module), GPSM (Global Positioning System Module), LTM (Liftgate/Trunk Module) AND RETM (Rear Entertainment Module) DISABLED

- Disconnect: SJB (Smart Junction Box) Fuse 14 (10A).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test.

Do all other MS-CAN (Medium Speed Controller Area Network) modules pass the network test?

Yes
INSTALL the removed fuse. GO to W9.

No
INSTALL the removed fuse. GO to W10.

W9 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE APIM (Accessory Protocol Interface Module), FDIM (Front Display Interface Module), GPSM (Global Positioning System Module), LTM (Liftgate/Trunk Module) AND RETM (Rear Entertainment Module) DISCONNECTED

- Disconnect: APIM (Accessory Protocol Interface Module) C3342 (If Equipped).

- Enter the following diagnostic mode on the scan tool: Network Test.

- If all other HS-CAN (High Speed Controller Area Network) modules pass the network test, skip to end of test step. Otherwise, continue.

- Disconnect: FDIM (Front Display Interface Module) C2123 (If Equipped).

- Enter the following diagnostic mode on the scan tool: Network Test.

- If all other HS-CAN (High Speed Controller Area Network) modules pass the network test, skip to end of test step. Otherwise, continue.

- Disconnect: GPSM (Global Positioning System Module) C2300 (If Equipped).

- Enter the following diagnostic mode on the scan tool: Network Test.

- If all other HS-CAN (High Speed Controller Area Network) modules pass the network test, skip to end of test step. Otherwise, continue.

- Disconnect: LTM (Liftgate/Trunk Module) C4174A (If Equipped).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test. If all other HS-CAN (High Speed Controller Area Network) modules pass the network test, skip to end of test step. Otherwise, continue.

- Disconnect: RETM (Rear Entertainment Module) C2949B (If Equipped).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test.

Do all other HS-CAN (High Speed Controller Area Network) modules pass the network test?

Yes
CONNECT all modules.

For APIM (Accessory Protocol Interface Module), GO to Pinpoint Test T. Pinpoint Test T: The Accessory Protocol Interface Module (APIM) Does Not Respond To The Scan Tool

For FDIM (Front Display Interface Module), GO to Pinpoint Test N. Pinpoint Test N: The Front Display Interface Module (FDIM) Does Not Respond To The Scan Tool

For GPSM (Global Positioning System Module), GO to Pinpoint Test S. Pinpoint Test S: The Global Positioning System Module (GPSM) Does Not Respond To The Scan Tool

For LTM (Liftgate/Trunk Module), GO to Pinpoint Test Q. Pinpoint Test Q: The Liftgate/Trunk Module (LTM) Does Not Respond To The Scan Tool

For RETM (Rear Entertainment Module), GO to Pinpoint Test P. Pinpoint Test P: The Rear Entertainment Module (RETM) Does Not Respond To The Scan Tool

No
An intermittent fault is not present. GO to Pinpoint Test X. Pinpoint Test X: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding

W10 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE HVAC MODULE DISABLED

- Disconnect: SJB (Smart Junction Box) Fuse 15 (10A).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test.

Do all other MS-CAN (Medium Speed Controller Area Network) modules pass the network test?

Yes
INSTALL the removed fuse. GO to Pinpoint Test J. Pinpoint Test J: The HVAC Module Does Not Respond To The Scan Tool

No
INSTALL the removed fuse.

If the vehicle is equipped with a DSM (Driver Seat Module), GO to W11.

If the vehicle is not equipped with a DSM (Driver Seat Module), GO to W12.

W11 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE DSM (Driver Seat Module) DISABLED

- Disconnect: BJB (Battery Junction Box) Fuse 32 (30A).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test.

Do all other MS-CAN (Medium Speed Controller Area Network) modules pass the network test?

Yes
INSTALL the removed fuse. GO to Pinpoint Test O. Pinpoint Test O: The Driver Seat Module (DSM) Does Not Respond To The Scan Tool

No
INSTALL the removed fuse. GO to W12.

W12 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE FCIM (Front Controls Interface Module) DISABLED

- Disconnect: Front Controls Interface Module (FCIM) Fuse 16 (15A).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test.

Do all other MS-CAN (Medium Speed Controller Area Network) modules pass the network test?

Yes
INSTALL the removed fuse. GO to Pinpoint Test M. Pinpoint Test M: The Front Controls Interface Module (FCIM) Does Not Respond To The Scan Tool

No
INSTALL the removed fuse. GO to W13.

W13 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE IC (Instrument Cluster) DISABLED

- Disconnect: SJB (Smart Junction Box) Fuses 26 (10A) and 29 (5A).

- Enter the following diagnostic mode on the scan tool: Network Test.

- Repeat the network test.

Do all other MS-CAN (Medium Speed Controller Area Network) modules pass the network test?

Yes
INSTALL the removed fuses. GO to Pinpoint Test C. Pinpoint Test C: The Instrument Cluster (IC) Does Not Respond To The Scan Tool

No
INSTALL the removed fuses. GO to Pinpoint Test X. Pinpoint Test X: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding