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DTC B278C: Lost Communication with Power Source Control [09/2014 - ]: Procedure

  1. CLEAR DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2014 - ]

      Body Electrical > Smart Access > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. CHECK FOR DTC 
    1. Check for DTCs.

      Refer to DTC CHECK / CLEAR [09/2014 - ]

      Body Electrical > Smart Access > Trouble Codes 

      OK

      DTC B278C is not output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2014 - 08/2016]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - 11/2017]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 03/2019]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [03/2019 - 09/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2020 - 01/2023]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [01/2023 - ] 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2014 - ]