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DTC U0073: Control Module Communication Bus OFF [05/2019 - ]: Procedure

  1. CHECK CAN COMMUNICATION SYSTEM 
    1. Check for malfunctions in the CAN communication system.

      Refer to DIAGNOSIS SYSTEM [05/2019 - 10/2019] , or refer to DIAGNOSIS SYSTEM [10/2019 - 07/2020] , or refer to DIAGNOSIS SYSTEM [07/2020 - ]

      Result

      Proceed to
      CAN communication system is normal
      CAN communication system is abnormal

    Result: 

    CAN communication system is abnormal 

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING). Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [05/2019 - ] 

    Result: 

    CAN communication system is normal 

    See step  2

  2. RECONFIRM DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [05/2019 - ]

      Chassis > Four Wheel Drive > Clear DTCs 

    2. Turn the engine switch off.
    3. Check if the same DTC is output.

      Refer to DTC CHECK / CLEAR [05/2019 - ]

      Chassis > Four Wheel Drive > Trouble Codes 

      Result

      Proceed to
      DTC U0073 is output.
      DTC U0073 is not output.

    Result: 

    DTC U0073 is output. 

    REPLACE 4WD ECU ASSEMBLY. Refer to  REMOVAL [05/2019 - ] 

    Result: 

    DTC U0073 is not output. 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [05/2019 - 10/2019]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2019 - 07/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]