LIN COMMUNICATION SYSTEM, Diagnostic DTC:B2789

DTC Code DTC Name
B2789 No Response from ID BOX

DESCRIPTION

This DTC is output 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

A009AD1E40

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.

      OK
      DTC B2789 is not output.

    NG

    CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - ID CODE BOX) Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

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


    1. Disconnect the G38 certification ECU connector.

    2. Disconnect the G37 ID code box connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G38-29 (LIN) - G37-3 (LIN1) Always Below 1 Ω
      G38-29 (LIN) or G37-3 (LIN1) - 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. A009C59E04
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ID Code Box)

      Disconnect the G37 ID code box connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G37-8 (GND) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      G37-1 (+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.


    NEXT

  6. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  7. CHECK FOR DTC


    1. Check for DTCs Click here.

      OK
      DTC B2789 is not output.

    NG

    REPLACE CERTIFICATION ECU

    OK

    END (ID CODE BOX IS DEFECTIVE)