LIN COMMUNICATION SYSTEM, Diagnostic DTC:B126A and B1269

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

DESCRIPTION

The main body ECU (multiplex network body ECU) communicates with the accessory ECUs via BERKES communication.

These DTCs are stored when communication between the main body ECU (multiplex network body ECU) and accessory ECU stops 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 for 10 seconds or more.

  • Accessory ECU

  • Main body ECU (multiplex network body ECU)

  • Wire harness or connector

B126A

Remote Engine Starter ECU Communication Stop

No communication between main body ECU (multiplex network body ECU) and accessory ECU for 10 seconds or more.

  • Accessory ECU

  • Main body ECU (multiplex network body ECU)

  • Wire harness or connector

WIRING DIAGRAM

E176055E16

CAUTION / NOTICE / HINT

Note:

Before starting repair, check that the power source system of the accessory ECU is not malfunctioning.

PROCEDURE

  1. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - OPTION CONNECTOR)

    1. Disconnect the E22 main body ECU (multiplex network body ECU) connector.

    2. Disconnect the E25 option connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E22-25 (BTX) - E25-1 (BTX)

      Always

      Below 1 Ω

      E22-26 (BRX) - E25-2 (BRX)

      Always

      Below 1 Ω

      E22-25 (BTX) - Body ground

      Always

      10 kΩ or higher

      E22-26 (BRX) - Body ground

      Always

      10 kΩ or higher

      E25-1 (BTX) - Body ground

      Always

      10 kΩ or higher

      E25-2 (BRX) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. REPLACE OPTION CONNECTOR

    1. Replace the option connector.

    Result

    Proceed to

    NEXT
    NEXT

  3. CHECK DTC OUTPUT

    1. Clear the DTCs.

      Click here

      Body Electrical > Main Body > Clear DTCs

    2. Recheck for DTCs.

      Body Electrical > Main Body > Trouble Codes

      OK

      DTC B126A and B1269 are not output.

    Result

    Proceed to

    OK

    NG
    OK

    END (OPTION CONNECTOR WAS DEFECTIVE)

    NG

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    for LHD:Click hereClick here

    for RHD:Click hereClick here