LIN COMMUNICATION SYSTEM, Diagnostic DTC:B2789

DTC Code DTC Name
B2789 No Response from ID BOX

DESCRIPTION

The certification ECU stores a DTC when communication with the ID code box is interrupted for more than a specified time.

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

  • Harness or connector

  • ID code box

  • Certification ECU

WIRING DIAGRAM

A0118WXE01

Tech Tips

When using the intelligent tester, repeatedly turn either front door courtesy light switch off-and-on at intervals of 1.5 seconds or less, until communication between the intelligent tester and vehicle begins.

Note


  • Inspect the fuses for this circuit before starting this inspection procedure.

  • Refer to the Service Bulletin for the installation position of the certification ECU.

INSPECTION PROCEDURE

PROCEDURE


  1. CLEAR DTC


    1. Clear 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 and B2785 are output B

      Tech Tips

      When both B2789 and B2785 are output at the same time, troubleshoot B2785 first.


    B

    GO TO DIAGNOSTIC TROUBLE CODE CHART Click here

    A

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


    1. A011BIGE01
      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 D34 certification ECU connector.

    2. Disconnect the D30 ID code box connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D34-29 (LIN) - D30-3 (LIN1) Always Below 1 Ω
      D34-29 (LIN) - Body ground Always 10 kΩ or higher
      Standard Voltage
      Tester Connection Condition Specified Condition
      D34-29 (LIN) - Body ground Always Below 0.5 V

    4. Reconnect the certification ECU connector.

    5. Reconnect the ID code box connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A0118FLE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ID Code Box)

      Disconnect the D30 ID code box connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D30-8 (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
      D30-1 (+B) - Body ground Always 11 to 14 V

    4. Reconnect the ID code box connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE ID CODE BOX NORMAL ONE


    1. Replace the ID code box with a normally functioning part (Refer to the Service Bulletin).

    2. Clear DTCs Click here.


    NEXT

  6. RECHECK FOR DTC


    1. Recheck 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 MALFUNCTION)