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

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B2789

No Response from ID BOX

No communication between certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) for 10 seconds or more.

  • ID code box (immobiliser code ECU)

  • Certification ECU (smart key ECU assembly)

  • Wire harness or connector

  • SMART fuse

WIRING DIAGRAM

B273275E64

CAUTION / NOTICE / HINT

Note:

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

  • If the certification ECU (smart key ECU assembly) is replaced, register the keys (refer to Service Bulletin).

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

  • When using the GTS with the engine switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.

PROCEDURE

  1. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ID CODE BOX (IMMOBILISER CODE ECU))

    1. Disconnect the E49 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the E48 ID code box (immobiliser code ECU) connector.

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

      Note:

      Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the engine switch from on (IG) to off and wait for 180 seconds or more without operating any switches.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E49-5 (LIN) - E48-2 (LIN1)

      Engine switch off

      Below 1 Ω

      E49-5 (LIN) or E48-2 (LIN1) - Body ground

      Engine switch off

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK HARNESS AND CONNECTOR (ID CODE BOX (IMMOBILISER CODE ECU) - BATTERY, BODY GROUND)

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      E48-1 (+B) - E48-5 (GND)

      Always

      11 to 14 V

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E48-5 (GND) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    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) with a new one.

      Tip:

      Refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  4. REGISTER ECU CODE REGISTRATION

    1. Register the recognition codes in the ECUs.

      Tip:

      Refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  5. CHECK DTC OUTPUT

    1. Clear the DTCs.

      Click here

      Body Electrical > Entry&Start > Clear DTCs

    2. Recheck for DTCs.

      Body Electrical > Entry&Start > Trouble Codes

      OK

      DTC B2789 is not output.

    Result

    Proceed to

    OK

    NG
    OK

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

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)