LIN COMMUNICATION SYSTEM, Diagnostic DTC:B1269 and B126A

DTC Code DTC Name
B1269 Theft Deterrent ECU Communication Stop
B126A Remote Engine Starter ECU Communication Stop

DESCRIPTION

The main body ECU (multiplex network body ECU) communicates with the accessory ECU and accessory BERKES.

This DTC is output when there is no communication between the main body ECU (multiplex network body ECU) and accessory ECU for 10 seconds or more.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1269

Theft Deterrent ECU Communication Stop

No communication between main body ECU (multiplex network body ECU) and accessory ECU (genuine auto alarm) (no communication for 10 seconds or more)

  • Main body ECU (multiplex network body ECU)

  • Option connector (accessory BERKES)

  • Wire harness and connector

B126A

Remote Engine Starter ECU Communication Stop

No communication between main body ECU (multiplex network body ECU) and accessory ECU (genuine remote engine starter) (no communication for 10 seconds or more)

  • Main body ECU (multiplex network body ECU)

  • Option connector (accessory BERKES)

  • Wire harness and connector

WIRING DIAGRAM

E342458E01

CAUTION / NOTICE / HINT

Note:

  • Before performing repairs, make sure there are no malfunctions in the power source circuit of the accessory ECU. (For details, refer to the installation procedures of the accessory manual.)

  • When using the GTS with the ignition switch off, turn a door courtesy light switch assembly on and off at intervals of 1.5 seconds or less until communication between the GTS and vehicle begins.

Tip:

For the circuit diagram of the accessory ECU, refer to the installation manual wiring diagram of the accessory manual.

PROCEDURE

  1. CHECK ACCESSORY ECU INSTALLATION

    1. Check if an accessory ECU (security ECU or remote engine starter ECU) is installed.

    Result

    Result

    Proceed to

    Part installed

    A

    Part not installed

    B
    B

    INITIALIZE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)Click here

    A

  2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] - OPTION CONNECTOR)

    1. Disconnect the G78 main body ECU (multiplex network body ECU) connector.

    2. Disconnect the G69 connector of the option connector (accessory BERKES).

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

      Standard Resistance

      Tester Connection

      Condition

      Specification Condition

      G78-25 (BTX) - G69-1 (BRX2)

      Always

      Below 1 Ω

      G78-26 (BRX) - G69-2 (BTX2)

      G78-25 (BTX) - Body ground

      Always

      10 kΩ or higher

      G78-26 (BRX) - Body ground

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE OPTION CONNECTOR (ACCESSORY BERKES) WITH NEW OR NORMALLY FUNCTIONING ONE

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE

  3. INITIALIZE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    Tip:

    When an accessory ECU (security ECU or remote engine starter ECU) connected to the main body ECU (multiplex network body ECU) is removed, initialize the main body ECU (multiplex network body ECU).

    1. Initialize ECU connection information

      1. Connect the GTS to the DLC3.

      2. Turn the ignition switch to ON.

      3. Turn the GTS on.

      4. Enter the following menus: Main Body / Utility / Initialize ECU Connection Information. Body Electrical

        Body Electrical > Main Body > Utility

        Tester Display

        Initialization

    Result

    Proceed to

    NEXT
    NEXT

  4. CHECK FOR DTC

    1. Check for DTCs.

      Click hereClick here

      Body Electrical > Main Body > Trouble Codes

    Result

    Result

    Proceed to

    B1269 and B126A are not output

    A

    B1269 or B126A is output (for LHD)

    B

    B1269 or B126A is output (for RHD)

    C
    A

    END

    B

    REPLACE MULTIPLEX NETWORK BODY ECU

    Click here

    C

    REPLACE MULTIPLEX NETWORK BODY ECU

    Click here