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Pinpoint Test AF : DTC U0257:00

WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.

  1. AF1 VERIFY THE CUSTOMER'S CONCERN

    • Ignition ON.
    • Verify if there is an observable symptom present.

    Is an observable symptom present? 

    Yes  GO to  AF2.
    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.

  2. AF2 CHECK THE COMMUNICATION NETWORK

    • Using a diagnostic scan tool, perform a network test.

    Does the FCDIM pass the network test? 

    Yes  GO to  AF3.
    No  REFER to Module Communications Network .

  3. AF3 RETRIEVE THE FCDIM DTCs

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

    Are any non-network DTCs recorded in the FCDIM ? 

    Yes  GO to  AF4.
    No  REFER to the FCDIM DTC Chart .

  4. AF4 RECHECK FOR DTC U0257:00

    • Using a diagnostic scan tool, clear all CMDTCs.
    • Ignition OFF.
    • Ignition ON.
    • Wait at least 10 seconds.
    • Using a diagnostic scan tool, retrieve the ACM, FCIM and APIM CMDTCs.

    Is DTC U0257:00 still set in the ACM, FCIM or APIM ? 

    Yes  GO to  AF5.
    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.

  5. AF5 RETRIEVE THE RECORDED DTCs FROM THE ACM, FCIM and APIM SELF-TEST

    • Using a diagnostic scan tool, perform the self-test for the following modules:
      • ACM
      • FCIM
      • APIM

    Are any non-network DTCs recorded? 

    Yes  REFER to the DTC Charts .
    No  GO to  AF6.

  6. AF6 CHECK FOR DTC U0257 SET IN MULTIPLE MODULES

    • Review the CMDTCs from all modules.

    Is DTC U0257:00 set in more than one module? 

    Yes  GO to  AF7.
    No  If there is an observable symptom, REFER to the Symptom Charts  to diagnose the observed symptom.If there is no observable symptom, the system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

  7. AF7 CHECK FOR CORRECT FCDIM OPERATION

    • Ignition OFF.
    • Disconnect and inspect the FCDIM connector.
    • Repair:
      • Corrosion (clean module pins or install new connectors or terminals)
      • Damaged or bent pins (install new terminals or pins)
      • Pushed-out pins (install new pins as necessary)
    • Reconnect the FCDIM connector. Make sure it seats and latches correctly.
    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new FCDIM. REFER to Front Controls/Display Interface Module (FCDIM) .
    No  The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.
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