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DTC U023A-87: Lost Communication with Image Processing Module "A" [11/2018 - 12/2021]: Procedure

  1. CHECK ELECTRONICALLY CONTROLLED BRAKE SYSTEM 
    1. Check the DTCs.

      for HV Model:

      Refer to DTC CHECK / CLEAR [11/2018 - 02/2019] , or refer to DTC CHECK / CLEAR [02/2019 - 12/2021]

      Chassis > ABS/VSC/TRAC > Trouble Codes 

      for Gasoline Model:

      Refer to DTC CHECK / CLEAR [11/2018 - ]

      Chassis > Brake/EPB > Trouble Codes 

      HINT: 

      If U023A-87 is output in the pre-collision system, electronically controlled brake system DTCs may also have been output. Check the electronically controlled brake system first.

      OK

      Electronically controlled brake system DTCs are not output.

      Result

      Result Proceed to
      OK (for Gasoline Model) A
      OK (for HV Model) B
      NG C

    Result: 

    See step  4

    Result: 

    GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM 

    for HV Model:

    Refer to DIAGNOSTIC TROUBLE CODE CHART [11/2018 - 02/2019] , or refer to DIAGNOSTIC TROUBLE CODE CHART [02/2019 - 10/2019] , or refer to DIAGNOSTIC TROUBLE CODE CHART [10/2019 - 06/2020] , or refer to DIAGNOSTIC TROUBLE CODE CHART [06/2020 - 08/2020] , or refer to DIAGNOSTIC TROUBLE CODE CHART [08/2020 - 12/2021]

    for Gasoline Model:

    Refer to DIAGNOSTIC TROUBLE CODE CHART [11/2018 - 10/2019] , or refer to DIAGNOSTIC TROUBLE CODE CHART [10/2019 - 08/2020] , or refer to DIAGNOSTIC TROUBLE CODE CHART [08/2020 - 12/2021]

    Result: 

    See step  2

  2. TEST MODE INSPECTION (ELECTRONICALLY CONTROLLED BRAKE SYSTEM) 

    HINT: 

    When entering Dealer Mode (Signal Check), the brake actuator assembly (skid control ECU) communicates with the forward recognition camera to judge whether the vehicle is equipped with the pre-collision system. Therefore, do not exit Dealer Mode (Signal Check) within 5 seconds of entering Dealer Mode (Signal Check).

    1. Procedure to Enter Test Mode (Signal Check)
      1. Turn the ignition switch off.
      2. Apply the parking brake.
      3. Check that the shift lever is in P.
      4. Connect the Techstream to the DLC3.
      5. Turn the ignition switch to ON.
      6. Check that the steering wheel is centered.
      7. Turn the Techstream on.
      8. Switch the brake actuator assembly (skid control ECU) to Dealer Mode (Signal Check) using the Techstream. Enter the following menus: Chassis / Brake/EPB / Utility / Signal Check.

        Chassis > Brake/EPB > Utility 

        Tester Display
        Signal Check

        HINT: 

        Do not exit Dealer Mode (Signal Check) within 5 seconds of entering Dealer Mode (Signal Check). If Dealer Mode (Signal Check) is exited within 5 seconds of entering Dealer Mode (Signal Check), DTC U023A-87 may be stored. If DTC U023A-87 is output after exiting Dealer Mode (Signal Check), enter Dealer Mode (Signal Check) again, wait at least 5 seconds, then recheck for DTCs.

    2. End of Dealer Mode (Signal Check)
      1. Turn the ignition switch off.
      2. Disconnect the Techstream.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  3

  3. CHECK FOR DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [11/2018 - 12/2021]

      Body Electrical > Pre-Collision System > Clear DTCs 

    2. Make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the system cannot detect the malfunction.

    3. Recheck for DTCs and check that no DTCs are output.

      Refer to DTC CHECK / CLEAR [11/2018 - 12/2021]

      Body Electrical > Pre-Collision System > Trouble Codes 

      OK

      DTC U023A-87 is not output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  REMOVAL [11/2018 - 12/2021] 

  4. TEST MODE INSPECTION (ELECTRONICALLY CONTROLLED BRAKE SYSTEM) 

    HINT: 

    When entering test mode, the brake booster with master cylinder assembly (skid control ECU) communicates with the forward recognition camera to judge whether the vehicle is equipped with the pre-collision system. Therefore, do not exit test mode within 5 seconds of entering test mode.

    1. Procedure to Enter Test Mode
      1. Turn the ignition switch to ON.
      2. Check that the steering wheel is centered.
      3. Check that the parking brake is released.
      4. Check that the shift lever is in P.
      5. Turn the ignition switch off.
      6. Connect the Techstream to the DLC3.
      7. Turn the ignition switch to ON.
      8. Turn the Techstream on.
      9. Switch the brake booster with master cylinder assembly (skid control ECU) to Test Mode using the Techstream. Enter the following menus: Chassis / ABS/VSC/TRAC / Utility / Signal Check.

        Chassis > ABS/VSC/TRAC > Utility 

        Tester Display
        Signal Check
      10. Check that the ABS warning, brake warning / yellow (minor malfunction) and slip indicator lights come on for several seconds and then blink in the Test Mode pattern.

        HINT: 

        • If the ABS warning, brake warning / yellow (minor malfunction) and slip indicator lights do not blink, inspect the ABS warning, brake warning / yellow (minor malfunction) and slip indicator light circuits.
        • Do not exit test mode within 5 seconds of entering test mode. If test mode is exited within 5 seconds of entering test mode, DTC U023A-87 may be stored. If DTC U023A-87 is output after exiting test mode, enter test mode again, wait at least 5 seconds, then recheck for DTCs.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  3