Pinpoint Test S: Abs Module Communication Concern With TBM

Normal Operation and Fault Conditions

The TBM module may also be known as the TRM.

With the ignition ON, the TBM sends messages to the GWM over the HS-CAN3. The GWM relays these messages to the ABS module over the FD-CAN. If the ABS module does not receive these messages within the allotted time frame or if the messages contain invalid data, the module sets a DTC. This can be due to a TBM failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the TRM TBM, REFER to: Anti-Lock Brake System (ABS) and Stability Control .

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Condition
ABS U0137:00	Lost Communication With Trailer Brake Control Module: No Sub Type Information	This DTC sets when the ABS module does not receive any messages from the TBM TRM within the allowed time.

Possible Causes

Network communication concern
GWM
TRM

S1 CHECK THE COMMUNICATION NETWORK

Ignition ON.

Press the Read Vehicle Information button to view the results of the modules communicating on the network.

Using a diagnostic scan tool, retrieve the DTC s from the vehicle.
NOTE: DTCs may be displayed from previous diagnostic actions.

Does the TBM pass the Network Test?

Yes	RETRIEVE and RECORD all TBM DTCs. REFER to Auxiliary Brake System - Vehicles With: Trailer Brake Control . If there are no DTCs in the TBM, GO to S3

GO to S2

S2 CHECK THE GWM (GATEWAY MODULE A) COMMUNICATION

Ignition ON.

Using a diagnostic scan tool, carry out the network test.

Using a diagnostic scan tool, retrieve DTC s from the vehicle.
NOTE: DTC s may be displayed from previous diagnostic actions.

Does the GWM pass the network test?

Yes	DIAGNOSE the TBM does not communicate with the diagnostic scan tool. REFER to: Controller Area Network (CAN) Module Communications Network .

No	DIAGNOSE the GWM does not communicate with the diagnostic scan tool. REFER to: Controller Area Network (CAN) Module Communications Network .

S3 RECHECK THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE DTC (DIAGNOSTIC TROUBLE CODE) S

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

Record all ABS module DTC s.

Using a diagnostic scan tool, clear all ABS module DTC s.

Ignition OFF.

Ignition ON.

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

Are any of the DTC s listed in the Fault Trigger Conditions Table retrieved again?

Yes

GO to S4

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.

S4 CHECK FOR VOLTAGE DTC (DIAGNOSTIC TROUBLE CODE) S IN THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE
- Review the results from the ABS module self-test.
Is DTC U3003:16 or U3003:17 present?

Yes For DTC U3003:16:
GO to Pinpoint Test A
For DTC U3003:17:
GO to Pinpoint Test F

No GO to S5

S5 RETRIEVE ALL DTC (DIAGNOSTIC TROUBLE CODE) S FROM THE GWM (GATEWAY MODULE A)
- Using a diagnostic scan tool, carry out the GWM self-test.
- Record all DTC s from the GWM self-test.
Are any DTC s present?

Yes DIAGNOSE the GWM DTC. REFER to: Controller Area Network (CAN) Module Communications Network .

No GO to S6

S6 RETRIEVE ALL DTCS FROM THE TBM (TRAILER BRAKE CONTROL MODULE)
- Using a diagnostic scan tool, carry out the TBM self-test.
- Record all DTC s from the TBM self-test.
Are any DTC s present?

Yes DIAGNOSE the TBM DTC. REFER to: Auxiliary Brake System - Vehicles With: Trailer Brake Control .

No GO to S7

S7 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 or the ABS module. 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 S8

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

S8 CHECK FOR COMMUNICATION DTC (DIAGNOSTIC TROUBLE CODE) S IN OTHER MODULES
- Ignition ON.
- Using a diagnostic scan tool, clear all ABS module DTC s.
- Using a diagnostic scan tool, retrieve the DTC s from the vehicle.
  NOTE: DTC s may be displayed from previous diagnostic actions. Only available in the on-line service information
Is DTC U0137:xx set in 1 or more modules in addition to the ABS module?

Yes GO to S9

No GO to S10

S9 VERIFY TBM (TRAILER BRAKE CONTROL MODULE) OPERATION

Ignition OFF.

Disconnect GWM C2431A.

Disconnect ABS Module C135.

Disconnect TRM C2496C.

Disconnect TRM C2496F.

Using a good light source, inspect all disconnected electrical connectors for the following:
- Corrosion - install new connector or terminal and clean the module pins
- Damaged or bent pins - install new terminals or pins
- Pushed-out pins - install new pins as necessary
- Spread terminals - install new terminals as necessary

Connect TRM C2496C. Make sure the connector seats and latches correctly.

Connect TRM C2496F. Make sure the connector seats and latches correctly.

Connect ABS Module C135. Make sure the connector seats and latches correctly.

Connect GWM C2431A. Make sure the connector seats and latches correctly.

Operate the system and verify the concern is still present.

Is the concern still present?

Yes

CHECK OASIS for any 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 services articles address this concern, INSTALL a new TBM. REFER to: Auxiliary Brake System - Vehicles With: Trailer Brake Control .

No	The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

S10 VERIFY ABS (ANTI-LOCK BRAKE SYSTEM) MODULE OPERATION

Ignition OFF.

Disconnect ABS Module C135.

Disconnect GWM C2431A.

Disconnect TRM C2496C.

Disconnect TRM C2496F.

Using a good light source, inspect all disconnected electrical connectors for the following:
- Corrosion - install new connector or terminal and clean the module pins
- Damaged or bent pins - install new terminals or pins
- Pushed-out pins - install new pins as necessary
- Spread terminals - install new terminals as necessary

Connect TRM C2496C. Make sure the connector seats and latches correctly.

Connect TRM C2496F. Make sure the connector seats and latches correctly.

Connect GWM C2431A. Make sure the connector seats and latches correctly.

Connect ABS Module C135. Make sure the connector seats and latches correctly.

Operate the system and verify the concern is still present.

Is the concern still present?

Yes	CHECK OASIS for any 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 services articles address this concern, INSTALL a new EBB unit. REFER to: Electric Brake Booster (EBB) .

No	The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.