LIN COMMUNICATION SYSTEM, Diagnostic DTC:B2789

DTC Code DTC Name
B2789 No Response from ID BOX

DESCRIPTION

This DTC is stored when LIN communication between the certification ECU and ID code box stops for 10 seconds or more.

DTC Code DTC Detection Condition Trouble Area
B2789 No communication between the certification ECU and ID code box for 10 seconds or more.

  • ID code box

  • Certification ECU

  • Harness or connector

WIRING DIAGRAM

A01ITX1E81

INSPECTION PROCEDURE

Note


  • When using the intelligent tester with the ignition switch off to troubleshoot:

    Connect the intelligent tester to the vehicle, and turn a courtesy light switch on and off at 1.5 second intervals until communication between the intelligent tester and vehicle begins.

  • Inspect the fuses and bulbs for circuits related to this system before performing the following inspection procedure.

Tech Tips

When communication between the ID code box and certification ECU stops, DTC B2785 is also stored.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC B2789 is output A
      DTC B2789 is not output B

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

  3. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - ID CODE BOX)


    1. A01ITKHE03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Certification ECU)
      *2

      Front view of wire harness connector

      (to ID Code Box)

      Disconnect the H51 ECU connector.

    2. Disconnect the H111 box connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H51-29 (LIN) - H111-3 (LIN1) Always Below 1 Ω
      H51-29 (LIN) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (ID CODE BOX - BATTERY AND BODY GROUND)


    1. A01IP0KE07
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ID Code Box)

      Disconnect the H111 box connector.

    2. Measure the resistance and voltage according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H111-8 (GND) - Body ground Always Below 1 Ω
      Standard Voltage
      Tester Connection Condition Specified Condition
      H111-1 (+B) - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE ID CODE BOX


    1. Temporarily replace the ID code box with a new one.

    2. Clear the DTCs Click here.


    NEXT

  6. CHECK FOR DTC


    1. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC B2789 is not output A
      DTC B2789 is output B

    B

    REPLACE CERTIFICATION ECU

    A

    END (ID CODE BOX IS DEFECTIVE)