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Pinpoint Test P : DTC (Diagnostic Trouble Code) U0253:00

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.

  1. P1 VERIFY THE CUSTOMER'S CONCERN

    • Ignition ON.

    • Verify there is an observable symptom present.

    Is an observable symptom present? 

    Yes  GO to  P2
    No  CLEAR the DTC. The system is operating normally at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

  2. P2 VERIFY THAT THE DIAGNOSTIC SCAN TOOL COMMUNICATES WITH THE APIM (SYNC MODULE)

    • Connect a diagnostic scan tool.

    • Check that a vehicle session can be established using the diagnostic scan tool.

    Can a vehicle session be established? 

    Yes  GO to  P3
    No  REFER to: Communications Network .

  3. P3 PERFORM THE IPMA (IMAGE PROCESSING MODULE A) SELF-TEST

    • Using a diagnostic scan tool, perform the IPMA self-test.

    • Clear the Diagnostic Trouble Codes (DTCs).

    • Wait 10 seconds.

    • Repeat the IPMA self-test.

    Are any non-network Diagnostic Trouble Codes (DTCs) present? 

    Yes  DIAGNOSE all non-network Diagnostic Trouble Codes (DTCs). REFER to the DTC Chart: IPMA .
    No  GO to  P4

  4. P4 PERFORM THE APIM (SYNC MODULE) SELF-TEST

    • Using a diagnostic scan tool, perform the APIM KOEO self-test.

    Are any non-network Diagnostic Trouble Codes (DTCs) present? 

    Yes  DIAGNOSE all non-network Diagnostic Trouble Codes (DTCs). SEE the APIM DTC Chart. Refer to the appropriate Information and Entertainment Systems article for the procedure.
    No  GO to  P5

  5. P5 PERFORM THE GWM (GATEWAY MODULE A) SELF-TEST

    • Using a diagnostic scan tool, perform the GWM self-test.

    Are any Diagnostic Trouble Codes (DTCs) recorded? 

    Yes  SEE the GWM DTC Chart. REFER to: Communications Network .
    No  GO to  P6

  6. P6 RECHECK THE IPMA (IMAGE PROCESSING MODULE A) DIAGNOSTIC TROUBLE CODES (DTCS)

    • Using a diagnostic scan tool, clear the IPMA Diagnostic Trouble Codes (DTCs).

    • Ignition OFF.

    • Ignition ON.

    • Wait 10 seconds.

    • Using a diagnostic scan tool, perform the continuous memory self-test.

    • Check the IPMA Diagnostic Trouble Codes (DTCs).

    Is DTC U0253:00 still present? 

    Yes  GO to  P7
    No  The system is operating correctly at this time. This DTC may have been set due to high network traffic or an intermittent fault condition.

  7. P7 CHECK FOR OTHER CAUSES OF COMMUNICATION NETWORK CONCERN

    NOTE: If new modules were installed prior to the DTC being set, the module configuration may 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 APIM, IPMA or GWM. If recent service history is found:

      • verify correct replacement module was installed

        • HVBOM may be used to verify correct part fitment

      • verify the configuration of replacement module was correct

        • re-configure 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  P8
    No  The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.

  8. P8 CHECK FOR CORRECT APIM (SYNC MODULE) OPERATION

    • Ignition OFF.

    • Disconnect and inspect all APIM connectors and related in-line connectors.

    • Repair:

      • corrosion (install new connector or terminals - clean module pins)
      • damaged or bent pins - install new terminals/pins
      • pushed-out pins - install new pins as necessary

    • Reconnect the ABS module connectors and related in-line connectors. Make sure they seat and latch correctly.

    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, Refer to APIM Guided Routine Testing .
    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.
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