Possible Causes
WARNING: This page is about a different car, the 2020 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
- Network communication concern
- Battery/charging system concern
- TBC
- ABS module
- S1: CHECK THE COMMUNICATION NETWORK
- Ignition ON, engine OFF.
- Press the Read Vehicle Information button to view the results of the modules communicating on the network.
- Retrieve the continuous memory DTCs.
- Does the TBC pass the Network Test?
Yes No RETRIEVE and RECORD all TBC DTCs. REFER to the Auxiliary Brake System article. If there are no DTCs in the TBC,
Go to S3.Go to S2.
- S2: CHECK THE GWM COMMUNICATION
- Ignition ON, engine OFF.
- Press the Read Vehicle Information button to view the results of the modules communicating on the network.
- Retrieve the continuous memory DTCs.
- Does the GWM pass the network test?
Yes No DIAGNOSE the TBC does not communicate with the diagnostic scan tool. REFER to the Module Communications Network article. DIAGNOSE the GWM does not communicate with the diagnostic scan tool. REFER to the Module Communications Network article.
- S3: RECHECK THE ABS MODULE DTCS
Carry out the ABS self-test.
- Record all ABS module DTCs.
- Clear the ABS DTCs.
- Ignition OFF.
- Ignition ON, engine OFF.
Carry out the ABS self-test.
- Are any of the DTCs listed in the Fault Trigger Conditions Table retrieved again?
Yes No Go to S4. 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 DTCS IN THE ABS MODULE
- Review the results from the ABS module self-test.
- Is DTC U3003:16 or U3003:17 present?
Yes No For DTC U3003:16, GO to PINPOINT TEST A .
For DTC U3003:17, GO to PINPOINT TEST F .Go to S5.
- S5: RETRIEVE ALL DTCS FROM THE GWM
Carry out the GWM self-test.
- Record all DTCs from the GWM self-test.
- Are any DTCs present?
Yes No DIAGNOSE the GWM DTC. REFER to the Module Communications Network article. Go to S6.
- S6: RETRIEVE ALL DTCS FROM THE TBC
- Using a diagnostics scan tool, carry out the TBC self-test.
- Record all DTCs from the TBC self-test.
- Are any DTCs present?
Yes No DIAGNOSE the TBC DTC. REFER to the Auxiliary Brake System article. 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 TBC 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 No Go to S8. The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.
- Check the vehicle service history for recent service actions related to the TBC or the ABS module. If recent service history is found:
- S8: CHECK FOR COMMUNICATION DTCS IN OTHER MODULES
- S9: VERIFY TBC OPERATION
- Ignition OFF.
- GWM connector disconnected. (C2431)
- S10: VERIFY ABS MODULE OPERATION
- Ignition OFF.