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 will be stored.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1243 GSW Terminal Circuit Malfunction A malfunction occurs in the GSW input circuit of the main body ECU (multiplex network body ECU).

  • Main body ECU (multiplex network body ECU)

  • Instrument panel junction block assembly

  • Airbag ECU assembly

  • Instrument panel wire

WIRING DIAGRAM

B0057KJE13
*1 Instrument Panel Junction Block Assembly
*2 Airbag ECU Assembly
*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

  • When DTC B1243 is output, the collision door lock release, shift-linked automatic door lock/unlock and speed-sensitive automatic door lock functions are prohibited.

  • If the main body ECU (multiplex network body ECU) is replaced, refer to the Service Bulletin.

  • 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.*

    *: w/ Door Control Battery

    Click here

  • If the airbag ECU assembly is replaced, refer to the Airbag System.

    Click here

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > Main Body > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Recheck for DTCs.

      Click here


      Body Electrical > Main Body > Trouble Codes
      OK
      DTC B1243 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

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


    1. B00581SC05
      *a

      Rear view of wire harness connector

      (to Airbag ECU 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 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 airbag ECU 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
      I58-18 (GSW) - Body ground Engine switch on (IG) 2.8 to 4.2 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIRBAG ECU ASSEMBLY Click here

    NG

  4. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - AIRBAG ECU 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 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 4D instrument panel junction block assembly connector.

    3. Disconnect the I58 airbag ECU assembly connector.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      4D-46 - I58-18 (GSW) Always Below 1 Ω
      4D-46 or I58-18 (GSW) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INSTRUMENT PANEL WIRE

    OK

  5. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.


    2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

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

      B00586JC01
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      A-24 (GSW) - 4D-46 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY for LHD: Click here for RHD: Click here