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How To Proceed With Troubleshooting [01/2023 - ]: Procedure

WARNING: This page is about a different car, the 2024 Lexus RC F and 2023 Lexus RC F. However, it is still accessible from the selected car via links, so may be relevant.
  1. VEHICLE BROUGHT TO WORKSHOP 

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  2

  2. CUSTOMER PROBLEM ANALYSIS 

    HINT: 

    • In troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment. To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
    • Gather as much information as possible for reference. Past problems that seem unrelated may also help in some cases.
    • The following 5 items are important points for problem analysis:
      What Vehicle model, system name
      When Date, time, occurrence frequency
      Where Road conditions
      Under what conditions? Driving conditions, weather conditions
      How did it happen? Problem symptoms

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  3

  3. PRE-CHECK 
    1. Measure the battery voltage.

      Standard voltage

      11 to 14 V

      HINT: 

      If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step.

    2. Check the fuses and relays.
    3. Check the connector connections and terminals to make sure that there are no abnormalities such as loose connections, deformation, etc.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  4

  4. CHECK COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM* 
    1. Using the Techstream, check for CAN communication system DTCs.

      Refer to DIAGNOSIS SYSTEM [01/2023 - 10/2023] , or refer to DIAGNOSIS SYSTEM [10/2023 - ]

      Result

      Result Proceed to
      CAN DTCs are not output A
      CAN DTCs are output B

    Result: 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [01/2023 - ] 

    Result: 

    See step  5

  5. CHECK FOR DTCs* 
    1. Using the Techstream, check for DTCs.

      Body Electrical > Front Radar Sensor > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      DTC C1A11-00 is output B
      DTCs other than C1A11-00 are output C

    Result: 

    See step  7

    Result: 

    GO TO DIAGNOSTIC TROUBLE CODE CHART (C1A11-00). Refer to  DTC C1A11-00: Front Radar Sensor Optical Axis Misalignment Malfunction [01/2023 - ] 

    Result: 

    See step  6

  6. RECONFIRM DTC OUTPUT* 
    1. Using the Techstream, clear the DTCs.

      Body Electrical > Front Radar Sensor > Clear DTCs 

    2. Reproduce the vehicle conditions that were present when the DTCs that were noted were stored.

      HINT: 

      Refer to each corresponding DTC for details on the detection conditions.

      Refer to DIAGNOSTIC TROUBLE CODE CHART [01/2023 - ] 

    3. Using the Techstream, check for DTCs.

      Body Electrical > Front Radar Sensor > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      DTCs are output B

    Result: 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [01/2023 - ]  

    Result: 

    See step  7

  7. CHECK VEHICLE CONTROL HISTORY* 
    1. Using the Techstream, check for Vehicle Control History (RoB).

      Body Electrical > Front Radar Sensor > Utility 

      Tester Display
      Vehicle Control History (RoB)
    2. Make a note of the output Vehicle Control History (RoB).

      Result

      Result Proceed to
      Vehicle Control History (RoB) codes are not output A
      Vehicle Control History (RoB) code X2026 or X2028 is output B
      Vehicle Control History (RoB) codes other than X2026 and X2028 are output C

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [01/2023 - ] 

    Result: 

    GO TO VEHICLE CONTROL HISTORY (X2026 or X2028). Refer to  VEHICLE CONTROL HISTORY [01/2023 - ] 

    Result: 

    See step  8

  8. RECONFIRM VEHICLE CONTROL HISTORY* 
    1. Using the Techstream, clear the Vehicle Control History (RoB).

      Body Electrical > Front Radar Sensor > Utility 

      Tester Display
      Vehicle Control History (RoB)
    2. Using the Techstream, check for Vehicle Control History (RoB).

      Body Electrical > Front Radar Sensor > Utility 

      Tester Display
      Vehicle Control History (RoB)

      Result

      Result Proceed to
      Vehicle Control History (RoB) codes are not output A
      Vehicle Control History (RoB) codes are output B

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [01/2023 - ] 

    Result: 

    GO TO VEHICLE CONTROL HISTORY. Refer to  VEHICLE CONTROL HISTORY [01/2023 - ]