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Pinpoint Test B: DTC U0121:00

WARNING: This page is about a different car, the 2013 Ford F-550 Super Duty, 2013 Ford F-450 Super Duty, 2013 Ford F-350 Super Duty, and 2013 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
  1. B1 VERIFY THE CUSTOMER CONCERN 
    • Ignition ON.
    • Verify that there is an observable symptom present.
    • Is an observable symptom present? 
    • Yes  : GO to B2.
    • No  : 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. B2 CHECK THE COMMUNICATION NETWORK 
    • Ignition ON.
    • Enter the following diagnostic mode on the scan tool: Network Test.
    • Carry out the network test.
    • Does the ABS module pass the network test? 
  3. B3 RETRIEVE THE RECORDED DTCs FROM THE BCM AND SELF-TEST 
    • Check for recorded BCM DTCs from the self-test.
    • Is DTC U3003:16 or DTC U3003:17 recorded? 
  4. B4 RECHECK THE BCM DTCs 
    NOTE: If new modules were installed prior to the DTC being set, the module configuration may be incorrectly set during Programmable Module Installation (PMI) or the PMI may not have been carried out.
    • Clear the DTCs. Repeat the BCM self-test.
    • Is DTC U0121:00 still present? 
    • Yes  : GO to B5.
    • 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. B5 CHECK FOR DTC U0121:00 SET IN OTHER MODULES 
    • Clear the DTCs.
    • Ignition OFF.
    • Ignition ON.
    • Wait 10 seconds.
    • Enter the following diagnostic mode on the scan tool: Self-Test.
    • Retrieve the continuous memory DTCs from all modules.
    • Is DTC U0121:00 set in any other module?