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DTC U023A: Lost Communication with Front Camera Module [10/2016 - 09/2018]: Procedure

  1. READ VALUE USING TECHSTREAM (CAN BUS CHECK) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: System Select / Can Bus Check.

      Refer to DIAGNOSIS SYSTEM [10/2016 - 10/2017] , or refer to DIAGNOSIS SYSTEM [10/2017 - 09/2018]

      CAN Bus Check 

      Result

      Result Proceed to
      All of the ECUs and sensors that are currently connected to the CAN communication system are displayed A
      None of the ECUs and sensors that are currently connected to the CAN communication system are displayed, or some of them are not displayed B

    Result: 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2016 - 09/2018] 

    Result: 

    See step  2

  2. CHECK FOR DTCs (PRE-COLLISION SYSTEM) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [10/2016 - 09/2020]

      Body Electrical > Pre-Collision 2 > Clear DTCs 

    2. Perform the following procedure.

      HINT: 

      If the following procedure is not performed, the previously output DTC cannot be detected.

      1. Turn the engine switch on (IG) and wait 2 seconds or more.
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [10/2016 - 09/2020]

      Body Electrical > Pre-Collision 2 > Trouble Codes 

      Result

      Result Proceed to
      DTC U1002 is not output A
      DTC U1002 is output B

    Result: 

    GO TO DTC CHART (U1002). Refer to  DTC U1002: Lost Communication with Gateway Module [10/2016 - 09/2018]  

    Result: 

    See step  3

  3. CHECK FOR OPEN IN CAN BUS MAIN LINES (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the cable from the negative (-) battery terminal.
    2. Disconnect the S18 forward recognition camera connector.
      GTY645455Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Forward Recognition Camera)
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      S18-6 (CANH) - S18-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
    4. Connect the S18 forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (NO. 12 CAN JUNCTION CONNECTOR - FORWARD RECOGNITION CAMERA) 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (POWER SOURCE VOLTAGE) 
    1. Disconnect the S18 forward recognition camera connector.
      GTY645458Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Forward Recognition Camera)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      S18-10 (GND) - Body ground Always Below 1 Ω
    3. Connect the cable to the negative (-) battery terminal.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      S18-7 (IGB) - Body ground Engine switch on (IG) 11 to 14 V
    5. Connect the S18 forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  COMPONENTS [10/2016 - 09/2020] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)