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DTC U023A-87: Lost Communication with Image Processing Module "A" Missing Message [08/2019 - ]: Procedure

  1. CHECK FOR DTCs 
    1. Using the Techstream, check for electronically controlled brake system DTCs.

      Chassis > ABS/VSC/TRAC > Trouble Codes 

      HINT: 

      If DTC U023A-87 and electronically controlled brake system DTCs are output, perform troubleshooting for the electronically controlled brake system first.

      Result

      Result Proceed to
      Electronically controlled brake system DTCs are not output A
      Electronically controlled brake system DTCs are output B

    Result: 

    GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2019 - ] 

    Result: 

    See step  2

  2. TEST MODE INSPECTION (ELECTRONICALLY CONTROLLED BRAKE SYSTEM) 

    HINT: 

    When entering Test Mode (Signal Check), the skid control ECU 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 (Signal Check) within 5 seconds of entering Test Mode (Signal Check).

    1. Procedure to Enter Test Mode (Signal Check)
      1. Turn the power switch off.
      2. Check that the steering wheel is centered.
      3. Check that the shift lever is in P.
      4. Connect the Techstream to the DLC3.
      5. Turn the power switch on (IG).
      6. Turn the Techstream on.
      7. Switch the skid control ECU assembly to Test Mode (Signal Check) using the Techstream. Enter the following menus: Chassis / ABS/VSC/TRAC / Utility / Signal Check.

        Chassis > ABS/VSC/TRAC > Utility 

        Tester Display
        Signal Check

        HINT: 

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

    2. Test Mode (Signal Check) Display Check
      1. 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.

    3. End of Test Mode (Signal Check)
      1. Turn the power switch off and disconnect the Techstream.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  3

  3. CHECK FOR DTCs 
    1. Clear the DTCs.

      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. Check for DTCs.

      Body Electrical > Pre-Collision System > Trouble Codes 

      Result

      Result Proceed to
      DTC U023A-87 is not output A
      DTC U023A-87 is output B

    Result: 

    END 

    Result: 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  COMPONENTS [08/2019 - ]