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

A004RXOE05
*a Certification ECU
*b from Battery
*c ID Code Box
*d LIN Communication Line

CAUTION / NOTICE / HINT

Note


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

    Connect the intelligent tester to the vehicle, and turn a courtesy 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 the 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. Recheck 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)

    A004Q44E02
    Text in Illustration
    *1

    Front view of wire harness connector

    (to Certification ECU)
    *2

    Front view of wire harness connector

    (to ID Code Box)

    1. Disconnect the D54 ECU connector.

    2. Disconnect the D26 box connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D54-29 (LIN) - D26-3 (LIN1) Always Below 1 Ω
      D54-29 (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. A004O50E02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ID Code Box)

      Disconnect the D26 box connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D26-8 (GND) - Body ground Always Below 1 Ω
      Standard Voltage
      Tester Connection Condition Specified Condition
      D26-1 (+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 or normally functioning one.

    2. Clear the DTCs Click here.


    NEXT

  6. CHECK FOR DTC


    1. Recheck for DTCs Click here.

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

    A

    END (ID CODE BOX IS DEFECTIVE)

    B

    REPLACE CERTIFICATION ECU