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 (smart key ECU assembly) and ID code box (immobiliser code ECU) stops for more than 10 seconds.

DTC Code DTC Detection Condition Trouble Area
B2789 No communication between the certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) for more than 10 seconds.

  • ID code box (Immobiliser code ECU)

  • Certification ECU (Smart key ECU assembly)

  • Wire harness or connector

  • ECU-B3 fuse

WIRING DIAGRAM

A01CG8JE07

INSPECTION PROCEDURE

Note


  • If the certification ECU (smart key ECU assembly) is replaced, register the key.

  • If the ID code box (immobiliser code ECU) is replaced, register the ECU code and ECU communication ID.

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

    Connect the intelligent tester to the DLC3, and turn the courtesy switch on and off at 1.5-second intervals until communication between the tester and vehicle begins.

PROCEDURE


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


    1. Disconnect the G15 ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G15-8 (GND) - Body ground Always Below 1 Ω
      Standard Voltage
      Tester Connection Condition Specified Condition
      G15-1 (+B) - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR, OR REPLACE FUSE

    OK

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


    1. Disconnect the G20 ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G20-10 (LIN) - G15-3 (LIN1) Always Below 1 Ω
      G20-10 (LIN) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. REPLACE ID CODE BOX (IMMOBILISER CODE ECU)


    1. Replace the ID code box (immobiliser code ECU).


    NEXT

  4. CHECK DTC OUTPUT


    1. Clear the DTC Click here.

    2. Recheck for DTCs.

      OK
      DTC B2789 is not output.

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

    END (ID CODE BOX (IMMOBILISER CODE ECU) IS DEFECTIVE)