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Pinpoint Test L: Intermittent No Medium Speed Controller Area Network (MS-CAN) Communication, One Or More Modules Are Not Respo




Communications Network

Pinpoint Test L: Intermittent No Medium Speed Controller Area Network (MS-CAN) Communication, One Or More Modules Are Not Responding During Network Test

Normal Operation

The Medium Speed Controller Area Network (MS-CAN) uses an unshielded twisted pair cable.

In the event that either the MS-CAN (+) or MS-CAN (-) circuit becomes open to a module on the network, unreliable network communication to all modules on the network may result.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Data Link Connector (DLC)


PINPOINT TEST L: INTERMITTENT NO MS-CAN COMMUNICATION, ONE OR MORE MODULES ARE NOT RESPONDING DURING NETWORK TEST

NOTE: Various modules set network DTCs during this test procedure. Clear DTCs from all modules after the diagnostic procedure is completed.

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery, Mounting and Cables Battery Disconnect.

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L1 CHECK THE DLC PINS FOR DAMAGE


- Ignition OFF.
- Disconnect the scan tool cable from the DLC.
- Inspect DLC pins 3 and 11 for damage.




- Are DLC pins 3 and 11 OK?

Yes
GO to L2.

No
REPAIR the DLC as necessary. CLEAR the DTCs. REPEAT the network test with the scan tool.

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L2 CHECK THE MS-CAN TERMINATION RESISTANCE


- Disconnect: Negative Battery Cable.
- Measure the resistance between the DLC C251-3, circuit 4-EC1 (GY/RD)/4-EC13 (GY/VT)/4-EC14 (GY/OG), harness side and the DLC C251-11, circuit 5-EC1 (BU/RD)/5-EC13 (BU/WH)/5-EC14 (BU/BK), harness side.




- Is the resistance between 36 and 44 ohms?

Yes
GO to L3.

No
CONNECT the negative battery cable. GO to Pinpoint Test K. Pinpoint Test K: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding

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L3 CHECK THE MS-CAN (+) AND MS-CAN (-) CIRCUITS FOR A SHORT TO GROUND


- Measure the resistance between the DLC C251-3, circuit 4-EC1 (GY/RD)/4-EC13 (GY/VT)/4-EC14 (GY/OG), harness side and ground; and between the DLC C251-11, circuit 5-EC1 (BU/RD)/5-EC13 (BU/WH)/5-EC14 (BU/BK), harness side and ground.




- Are the resistances greater than 1,000 ohms?

Yes
CONNECT the negative battery cable. GO to L4.

No
CONNECT the negative battery cable. GO to Pinpoint Test K. Pinpoint Test K: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding

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L4 CHECK THE MS-CAN (+) AND MS-CAN (-) CIRCUITS FOR A SHORT TO VOLTAGE


- Ignition ON.
- Measure the voltage between the DLC C251-3, circuit 4-EC1 (GY/RD)/4-EC13 (GY/VT)/4-EC14 (GY/OG), harness side and ground; and between the DLC C251-11, circuit 5-EC1 (BU/RD)/5-EC13 (BU/WH)/5-EC14 (BU/BK), harness side and ground.




- Are the voltages greater than 6 volts?

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

No
GO to L5.

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L5 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE ACM AND SRM DISABLED


NOTE: When re-running the network test, the network test application must be closed first or the screen display reverts back to the prior run network test results.

- Disconnect: Central Junction Box (CJB) Fuse 151 (15A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other modules pass the network test?

Yes
INSTALL the removed fuse.

If the vehicle is equipped with a Speech Recognition Module (SRM), GO to L6.

If the vehicle is not equipped with a SRM, GO to Pinpoint Test E. Pinpoint Test E: The Audio Control Module (ACM) Does Not Respond To The Scan Tool

No
INSTALL the removed fuse. GO to L7.

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L6 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE ACM DISCONNECTED


NOTE: When re-running the network test, the network test application must be closed first or the screen display reverts back to the prior run network test results.

- Disconnect: ACM C240b.
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other modules pass the network test?

Yes
CONNECT the ACM. GO to Pinpoint Test E. Pinpoint Test E: The Audio Control Module (ACM) Does Not Respond To The Scan Tool

No
CONNECT the ACM. GO to Pinpoint Test F. Pinpoint Test F: The Speech Recognition Module (SRM) Does Not Respond To The Scan Tool

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L7 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE OCSM AND RCM DISABLED


NOTE: When re-running the network test, the network test application must be closed first or the screen display reverts back to the prior run network test results.

- Disconnect: Central Junction Box (CJB) Fuse 162 (7.5A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other modules pass the network test?

Yes
INSTALL the removed fuse. GO to L8.

No
INSTALL the removed fuse. GO to L9.

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L8 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE OCSM DISCONNECTED


NOTE: When re-running the network test, the network test application must be closed first or the screen display reverts back to the prior run network test results.

- Disconnect: OCSM C3159.
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other modules pass the network test?

Yes
CONNECT the OCSM. GO to Pinpoint Test G. Pinpoint Test G: The Occupant Classification System Module (OCSM) Does Not Respond To The Scan Tool

No
CONNECT the OCSM. GO to Pinpoint Test H. Pinpoint Test H: The Restraints Control Module (RCM) Does Not Respond To The Scan Tool

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L9 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE IC, GEM AND TPMS MODULE DISABLED


NOTE: When re-running the network test, the network test application must be closed first or the screen display reverts back to the prior run network test results.

- Disconnect: CJB Fuses 148 (7.5A) and 179 (7.5A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other modules pass the network test?

Yes
INSTALL the removed fuses. GO to L10.

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

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L10 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE IC DISCONNECTED


NOTE: When re-running the network test, the network test application must be closed first or the screen display reverts back to the prior run network test results.

- Disconnect: IC C220b.
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other modules pass the network test?

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

No
CONNECT the IC. GO to L11.

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L11 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE GEM DISCONNECTED


NOTE: When re-running the network test, the network test application must be closed first or the screen display reverts back to the prior run network test results.

- Disconnect: GEM C201b.
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other modules pass the network test?

Yes
CONNECT the GEM. GO to Pinpoint Test J. Pinpoint Test J: The Generic Electronic Module (GEM) Does Not Respond To The Scan Tool

No
CONNECT the GEM. GO to Pinpoint Test I. Pinpoint Test I: The Tire Pressure Monitoring System (TPMS) Module Does Not Respond To The Scan Tool

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