POWER DOOR LOCK CONTROL SYSTEM, Diagnostic DTC:B1243

DTC Code DTC Name
B1243 GSW Terminal Circuit Malfunction

DESCRIPTION

If the collision door lock release function does not operate normally, or an open or short in the GSW input circuit of the main body ECU (multiplex network body ECU) is detected, DTC B1243 is stored.

Tech Tips

If DTC B1243 is stored, the speed-sensitive automatic door lock function, shift-linked automatic door lock function, and collision door lock release function are prohibited.

DTC Code DTC Detection Condition Trouble Area
B1243

When either of the following occurs:


  • An open or short in the GSW input circuit of the main body ECU (multiplex network body ECU).

  • The collision door lock release function does not operate normally.

  • Harness or connector

  • Center airbag sensor assembly

  • Main body ECU (multiplex network body ECU)

WIRING DIAGRAM

B001AY4E07
*1 Center Airbag Sensor Assembly
*2 Cowl Side Junction Block LH
*3 Main Body ECU (Multiplex Network Body ECU)

CAUTION / NOTICE / HINT

Note


  • After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work Click here.

  • When disconnecting the cable from the negative (-) battery terminal while performing repairs, some systems need to be initialized after the cable is reconnected Click here.

  • As the door control battery is installed between the vehicle battery and main body ECU (multiplex network body ECU), first perform the inspections in On-Vehicle Inspection to confirm that there are no malfunctions in the power source circuit for the main body ECU (multiplex network body ECU) before performing this troubleshooting procedure Click here.

PROCEDURE


  1. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1243 is not output.

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  2. CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (GSW VOLTAGE)


    1. B0018B0E02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Airbag Sensor Assembly)

      Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note

      Turning the engine switch to On (IG) with the airbag ECU assembly connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    2. Disconnect the center airbag sensor assembly connector Click here.

    3. Connect the cable to the negative (-) battery terminal.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      E47-18 (GSW) - Body ground Engine switch On (IG) 2.8 to 4.3V

    NG

    REPLACE AIRBAG SENSOR ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (COWL SIDE JUNCTION BLOCK LH - AIRBAG SENSOR ASSEMBLY)


    1. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note

      Turning the engine switch to On (IG) with the airbag ECU assembly connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    2. Disconnect the 2I cowl side junction block LH connector.

    3. Disconnect the E47 airbag sensor assembly connector Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2I-7 - E47-18 (GSW) Always Below 1 Ω
      2I-7 or E47-18 (GSW) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT COWL SIDE JUNCTION BLOCK LH


    1. Remove the cowl side junction block LH.


    2. Remove the main body ECU (multiplex network body ECU) from the cowl side junction block LH.

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

      B00184YE05
      Text in Illustration
      *a

      Component without harness connected

      (Cowl Side Junction Block LH)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      A-24(GSW) - 2I-7 Always Below 1 Ω
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG (for LHD) C
      NG (for RHD) D

    A

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (for LHD) Click here

    B

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (for RHD) Click here

    C

    REPLACE COWL SIDE JUNCTION BLOCK LH (for LHD) Click here

    D

    REPLACE COWL SIDE JUNCTION BLOCK LH (for RHD) Click here