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DTC U023A-87: Lost Communication with Image Processing Module "A" [05/2019 - ]: Procedure

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

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

      Chassis > ABS/VSC/TRC > Trouble Codes 

      HINT: 

      If U023A87 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 OK
      NG NG

    Result: 

    NG 

    GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM. Refer to  DIAGNOSTIC TROUBLE CODE CHART [05/2019 - 07/2020]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [07/2020 - ] 

    Result: 

    OK 

    See step  2

  2. TEST MODE INSPECTION (ELECTRONICALLY CONTROLLED BRAKE SYSTEM) 

    HINT: 

    When entering test mode, the skid control ECU (brake booster with master cylinder assembly) 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 power switch on (IG).
      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 power switch off.
      6. Connect the Techstream to the DLC3.
      7. Turn the power switch on (IG).
      8. Turn the Techstream on.
      9. Switch the skid control ECU (brake booster with master cylinder assembly) to Test Mode using the Techstream. Enter the following menus: Chassis / ABS/VSC/TRC / Utility / Signal Check.

        Chassis > ABS/VSC/TRC > 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 U023A87 may be stored. If DTC U023A87 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

  3. CHECK FOR DTC 
    1. Clear the DTCs

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

    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 [05/2019 - ]

      OK

      DTC U023A87 is not output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  REMOVAL [05/2019 - ] 

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