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Home >> Lexus >> 2019 >> UX 250h Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Smart Access System W/ Push-Button Start (Start Function) (Diagnostic Codes & Symptom Tests (1 Of 2)) (Hybrid) >> SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function, HV Model) >> DTC B2790: ID BOX EEPROM Malfunction [10/2018 - ] >> Procedure
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DTC B2790: ID BOX EEPROM Malfunction [10/2018 - ]: Procedure

  1. REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 
    1. Replace the ID code box (immobiliser code ECU) with a new one.

      Refer to REMOVAL [10/2018 - 07/2022] Refer to REMOVAL [07/2022 - ]

      HINT: 

      Refer to Registration.

      Refer to REGISTRATION [10/2018 - 10/2019] Refer to REGISTRATION [10/2019 - 07/2022] Refer to REGISTRATION [07/2022 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. CLEAR DTC 
    1. Clear the DTCs.

      Body Electrical > Smart Access > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  3

  3. REGISTER RECOGNITION CODES 
    1. Register the recognition codes to the ECUs.

      HINT: 

      Refer to Registration.

      Refer to REGISTRATION [10/2018 - 10/2019] Refer to REGISTRATION [10/2019 - 07/2022] Refer to REGISTRATION [07/2022 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  4

  4. REGISTER ECU COMMUNICATION ID (ID CODE BOX (IMMOBILISER CODE ECU) - HYBRID VEHICLE CONTROL ECU ASSEMBLY) 
    1. Register the ECU communication ID codes.

      HINT: 

      Refer to Registration.

      Refer to REGISTRATION [10/2018 - 10/2019] Refer to REGISTRATION [10/2019 - 07/2022] Refer to REGISTRATION [07/2022 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

  5. CHECK FOR DTC 
    1. Check for DTCs.

      Body Electrical > Smart Access > Trouble Codes 

      HINT: 

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

      Result

      Result Proceed to
      DTC B2790 is not output. A
      DTC B2790 is output. B

    Result: 

    END (ID CODE BOX (IMMOBILISER CODE ECU) WAS DEFECTIVE) 

    Result: 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [10/2018 - 07/2022]  Refer to  REMOVAL [07/2022 - ]