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Inspection steps

WARNING: This page is about a different car, the 2014 Subaru BRZ. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION: Perform this procedure after performing until STEP 9 in "How to troubleshoot". (Refer to HOW TO TROUBLESHOOT  )
  1. Check DTC
    1. Check the displayed DTC.

      Criteria: DTCs other than U**** are not output

      NO: Perform the diagnosis according to the DTC.

      YES: Go to Next Step

  2. Check DTC
    1. Check the displayed DTC.

      Criteria: No DTC indicating bus off or missing data is output

      NO: Perform the diagnosis according to the DTC.

      YES: Go to Next Step

  3. Check DTC
    1. Check the displayed DTC.

      Criteria: U0427 is output

      NO: Go to "How to simulate trouble phenomenon" (Refer to PROCEDURES FOR MALFUNCTION PHENOMENON SIMULATION )

      YES: Go to Next Step

  4. Check DTC
    1. Turn the ignition switch to OFF.
    2. Disconnect the collation ECM (Smart key computer assembly) connector.
    3. Reconnect the disconnected connector and turn the ignition switch ON.
    4. Use SSM3 to read DTC.

      Criteria: U0427 is output

      NO: Go to "How to simulate trouble phenomenon" (Refer to PROCEDURES FOR MALFUNCTION PHENOMENON SIMULATION )

      YES: Go to Next Step

  5. Check DTC
    1. Use SSM3 to read DTCs of all the systems.

      Criteria: U0427 is not detected from more than one module

      NO: Replace the collation ECM (Smart key computer assembly).

      YES: Go to Next Step

  6. Replace the module
    1. Replace the collation ECM (Smart key computer assembly).
    2. Use SSM3 to read DTC.

      Criteria: U0427 is output

      NO: System is normal.

      YES: Go to Next Step

  7. Replace the module
    1. Reinstall the collation ECM (Smart key computer assembly).
    2. Replace the module that DTC has been detected.
    3. Use SSM3 to read DTC.

      Criteria: U0427 is output

      NO: System is normal.

      YES: Replace the collation ECM (Smart key computer assembly).