Pinpoint Test I : U0137:87

WARNING: This page is about a different variant/trim than selected.

Refer to the appropriate Wiring Diagram for schematic and connector information.

Normal Operation and Fault Conditions

With the ignition ON, the TBM sends messages to the VDM over the HS-CAN2. If the VDM does not receive these messages within a certain time frame, the module sets Diagnostic Trouble Codes (DTCs). For information on the messages sent to the VDM by the TBM, go to the Network Message Chart. REFER to: Vehicle Dynamic Suspension - Overview .

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Condition
VDM U0137:87	Lost Communication With Trailer Brake Control Module: Missing Message	This DTC sets in continuous memory due to a TBM failure, a circuit failure on the HS-CAN or an excessive load on the network.

Possible Sources

Wiring, terminals or connectors
Network communication concern
Vehicle battery
Charging system concern
RCM

I1 CHECK THE COMMUNICATION NETWORK
- Ignition ON.
- Using a diagnostic scan tool, carry out the Network Test.
Does the TBM pass the Network Test?

Yes GO to I2

No DIAGNOSE the TBM or does not respond to the diagnostic scan tool. REFER to: Communications Network .

I2 CHECK THE TBM (TRAILER BRAKE CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

Using a diagnostic scan tool, carry out the TBM self-test.

Clear the Diagnostic Trouble Codes (DTCs).

Ignition OFF.

Ignition ON.

Using a diagnostic scan tool, carry out the TBM self-test.

Record the TBM Diagnostic Trouble Codes (DTCs).

Is DTC U0137:87 retrieved again?

Yes

GO to I3

No	The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

I3 REVIEW THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE TBM (TRAILER BRAKE CONTROL MODULE) SELF-TEST
- Check the recorded Diagnostic Trouble Codes (DTCs) from the TBM self-test.
Is DTC U3003:16 or U3003:17 present in the TBM?

Yes If DTC U3003:16 is present, GO to Pinpoint Test A If DTC U3003:17 is present, GO to Pinpoint Test B

No GO to I4

I4 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS) IN THE TBM (TRAILER BRAKE CONTROL MODULE)
- Using a diagnostic scan tool, carry out the TBM self-test.
Are any Diagnostic Trouble Codes (DTCs) present in the TBM?

Yes DIAGNOSE the TBM Diagnostic Trouble Codes (DTCs). REFER to: Electronic Engine Controls .

No GO to I5

I5 CHECK FOR OTHER CAUSES OF COMMUNICATION NETWORK CONCERN

NOTE: If new modules were installed prior to the DTC being set, the module configuration can be incorrectly set during the PMI or the PMI may not have been carried out.

Check the vehicle service history for recent service actions related to the TBM. If recent service history is found:
- verify the correct replacement module was installed.
  - HVBOM may be used to verify correct part fitment.
- verify the configuration of replacement module was correct.
  - re-configure the module using as-built data if prior configuration is suspect.
- verify the module was not obtained from a like vehicle and installed into customer vehicle.
  - return the swapped module to source vehicle and obtain new replacement module.

Operate the system and determine if the observable symptom is still present.

Is the observable symptom still present?

Yes

GO to I6

No	The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.

I6 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0137:XX SET IN OTHER MODULES

Using a diagnostic scan tool, carry out the self-test for all modules.

Is DTC U0137:xx set in 1 or more modules in addition to the TBM?

Yes

CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no Technical Service Bulletins (TSBs) exist for this concern, INSTALL a new TBM module. REFER to: Electronic Engine Controls .