LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2010 >> IS 250 AWD >> Repair and Diagnosis (Single Page) >> Body & Frame >> Door Locks >> Engine Immobiliser (Diagnostic Codes & Circuit Tests) >> Engine Immobilizer System >> DTC B2785: Communication Malfunction between ECUs Connected by LIN; DTC B2786: No Response from Steering Lock ECU; DTC B2789: No Response from ID BOX >> Inspection Procedure >> Procedure

Inspection Procedure: Procedure

  1. CHECK HARNESS AND CONNECTOR (LIN COMMUNICATION LINE AND BODY GROUND) 
    1. Disconnect the P33, J29, J55 and J69 ECU connectors.
      Fig 1: Identifying P33, J29, J55 & J69 ECU Connectors
      GTY120076Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      P33-10 (LIN) - J69-3 (LIN1) Always Below 1 Ω
      P33-10 (LIN) - J55-30 (LIN1) Always Below 1 Ω
      P33-10 (LIN) -J29-5 (LIN) Always Below 1 Ω
      P33-10 (LIN) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  2. CHECK DTC OUTPUT 
    1. Delete the DTCs. Refer to DTC CHECK / CLEAR .
    2. Recheck for DTCs. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      B2785 and B2786 outputs reoccur A
      B2785 and B2789 outputs reoccur B
      B2785 output reoccurs C

    C → See step   10 

    B → See step   6 

    A: Go to next step 

  3. REPLACE STEERING LOCK ECU 
    1. Replace the steering lock ECU.

    NEXT: Go to next step 

  4. ECU CODE REGISTRATION 
    1. Register the ECU communication ID between the ECUs connected by LIN communication. Refer to REGISTRATION .

    NEXT: Go to next step 

  5. CHECK DTC OUTPUT 
    1. Check for DTCs. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      B2785 and B2786 output or B2786 output reoccurs A
      Neither B2785 and B2786 output nor B2786 output reoccurs B

    B → END 

    A → REPLACE CERTIFICATION ECU 

  6. REPLACE ID CODE BOX 

    NEXT: Go to next step 

  7. ELECTRICAL KEY REGISTRATION 
    1. Register the electrical key code in the certification ECU. Refer to REGISTRATION .

    NEXT: Go to next step 

  8. ECU COMMUNICATION ID REGISTRATION 
    1. Register the ECU communication ID between the ID code box and ECM. Refer to REGISTRATION .

    NEXT: Go to next step 

  9. CHECK DTC OUTPUT 
    1. Check for DTCs. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      B2785 and B2789 output B2789 output reoccurs A
      Neither B2785 and B2789 output nor B2789 output reoccurs B

    B → END 

    A → REPLACE CERTIFICATION ECU 

  10. REPLACE CERTIFICATION ECU 
    1. Replace the certification ECU.

    NEXT: Go to next step 

  11. ELECTRICAL KEY REGISTRATION 
    1. Register the electrical key code in the certification ECU. Refer to REGISTRATION .

    NEXT: Go to next step 

  12. ECU COMMUNICATION ID REGISTRATION 

    Register the ECU communication ID between the ID code box and ECM. Refer to REGISTRATION .

    NEXT: Go to next step 

  13. CHECK DTC OUTPUT 
    1. Check for DTCs. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      B2785 output reoccurs A
      B2785 output does not reoccur B

    B → END 

    A: Go to next step 

  14. REPLACE POWER SOURCE CONTROL ECU 
    1. Replace the power source control ECU.

    NEXT: Go to next step 

  15. ECU CODE REGISTRATION 
    1. Register the ECU communication ID between the ECUs connected by LIN communication. Refer to REGISTRATION .

    NEXT: Go to next step 

  16. CHECK DTC OUTPUT 
    1. Check for DTCs. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      B2785 output reoccurs A
      B2785 output does not reoccur B

    B → END 

    A: Go to next step 

  17. REPLACE STEERING LOCK ECU 
    1. Replace the steering lock ECU.

    NEXT: Go to next step 

  18. ECU CODE REGISTRATION 
    1. Register the ECU communication ID between the ECUs connected by LIN communication. Refer to REGISTRATION .

    NEXT: Go to next step 

  19. CHECK DTC OUTPUT 
    1. Check for DTCs. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      B2785 output reoccurs A
      B2785 output does not reoccur B

    B → END 

    A → REPLACE ID CODE BOX 

scientia non olet · About LEMON Manuals