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Home >> Lexus >> 2024 >> NX 250 FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 9 (Electronically Controlled Brake System - Diagnostic Codes (3 Of 6)) >> ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for HEV Model) >> DTC C124A-05: Braking System information System Programming Failure [11/2021 - 03/2024] >> Procedure

DTC C124A-05: Braking System information System Programming Failure [11/2021 - 03/2024]: Procedure

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  1. CHECK PART NUMBER (HYBRID VEHICLE CONTROL ECU) 
    1. Check that the proper hybrid vehicle control ECU is installed.

      OK

      Proper hybrid vehicle control ECU is installed.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE HYBRID VEHICLE CONTROL ECU. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    OK 

    See step  2

  2. CHECK PART NUMBER (BRAKE ACTUATOR ASSEMBLY) 
    1. Check that the proper No. 2 skid control ECU (brake actuator assembly) is installed.

      OK

      Proper No. 2 skid control ECU (brake actuator assembly) is installed.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    OK 

    See step  3

  3. CLEAR SYSTEM INFORMATION 
    1. Clear system information.

      Refer to RESET MEMORY / CALIBRATION [11/2021 - ]

      Chassis > Brake/EPB > Utility 

      Tester Display
      Reset Memory

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  4

  4. SYSTEM INFORMATION MEMORIZATION 
    1. Perform system information memorization.

      Refer to RESET MEMORY / CALIBRATION [11/2021 - ]

      Chassis > Brake/EPB > Utility 

      Tester Display
      Calibration

      HINT: 

      After performing "Reset Memory" using the GTS to clear the memorized value of the No. 2 skid control ECU (brake actuator assembly), DTC C124A-05 will be stored until system information memorization is performed.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

  5. CLEAR DTC 
    1. Clear the DTCs.

      Chassis > Brake/EPB > Clear DTCs 

    2. Turn the ignition switch off.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  6

  6. RECONFIRM DTC 
    1. Based on the Freeze Frame Data and interview with the customer, attempt to reproduce the conditions when the malfunction occurred.
    2. Check if the same DTC is output.

      Chassis > Brake/EPB > Trouble Codes 

      Result

      Result Proceed to
      DTC C124A-05 is not output. A
      DTC C124A-05 is output. B

    Result: 

    END 

    Result: 

    REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [11/2021 - ]