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DTC U1119: Lost Communication with Object Recognition ECU (CAN): Procedure

  1. CHECK DTC OUTPUT 
    1. Using the Techstream, enter the following menus: Body Electrical / Pre-Collision 2 / Trouble Codes.
    2. Check for DTCs. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      DTC U1119 is output A
      DTC other than U1119 is output B

    B → See step   9 

    A: Go to next step 

  2. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Pre-Collision 2/ Data List / Recog ECU H Temp Hist.
    5. Confirm the judgment history.

      Pre-Collision 2

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Recog ECU H Temp Hist Lane recognition ECU temperature condition history/ ON or OFF ON: History exists
      OFF: No history
      -

      Result

      Result Proceed to
      ON is displayed A
      OFF is displayed B

    B → See step   6 

    A: Go to next step 

  3. CHECK HARNESS OR CONNECTOR (DRIVING SUPPORT ECU - LANE RECOGNITION CAMERA SENSOR) 
    1. Disconnect the driving support ECU connector and lane recognition camera sensor connector.
      Fig 1: Identifying Driving Support ECU - Lane Recognition Camera Sensor Connector
      GTY293552Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Condition Condition Specified Condition
      U4-5 (HITP) - L60-24 (HITP) Always Below 1 Ω
      U4-5 (HITP) or L60-24 (HITP) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Lane Recognition Camera Sensor Assembly)
      *2 Front view of wire harness connector
      (to Driving Support ECU)
    3. Reconnect the connectors.

    NG → See step   4 

    OK → See step   11 

  4. REPAIR OR REPLACE HARNESS OR CONNECTOR (DRIVING SUPPORT ECU - LANE RECOGNITION CAMERA SENSOR) 
    1. Repair or replace harness or connector.

    NEXT: Go to next step 

  5. CHECK DTC OUTPUT 
    1. Using the Techstream, enter the following menus: Body Electrical / Pre-Collision 2 / Trouble Codes.
    2. Clear the DTC. Refer to DTC CHECK / CLEAR .
    3. Turn the power switch off.
    4. Start the engine.
    5. Drive the vehicle and operate lane keeping assist control.
    6. Check for DTCs. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      DTC U1119 is not output A
      DTC U1119 is output B

    B → See step   9 

    A → END 

  6. CHECK CAN COMMUNICATION SYSTEM 
    1. Check CAN communication system. Refer to HOW TO PROCEED WITH TROUBLESHOOTING .

    NG → GO TO CAN COMMUNICATION CIRCUIT 

    OK: Go to next step 

  7. REPLACE LANE RECOGNITION CAMERA SENSOR ASSEMBLY 
    1. Replace lane recognition camera sensor assembly. Refer to REMOVAL .
    2. Adjust the lane recognition camera sensor assembly. Refer to ADJUSTMENT .

    NEXT: Go to next step 

  8. CHECK DTC OUTPUT 
    1. Using the Techstream, enter the following menus: Body Electrical / Pre-Collision 2 / Trouble Codes.
    2. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    3. Turn the power switch off.
    4. Turn the power switch on (IG).
    5. Drive the vehicle and operate lane keeping assist control.
    6. Recheck for DTCs.

      OK

      DTC is not output.

    NG → See step   10 

    OK → END 

  9. GO TO CAN COMMUNICATION CIRCUIT. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
  10. REPLACE DRIVING SUPPORT ECU. Refer to  REMOVAL 
  11. REPLACE LANE RECOGNITION CAMERA SENSOR ASSEMBLY. Refer to  REMOVAL