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.

Tech Tips

If DTC B1243 is stored, the automatic door lock function, and collision door lock release function will be prohibited.

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 sensor assembly

  • Wire harness or connector

WIRING DIAGRAM

B00855LE38
*1 Instrument Panel Junction Block Assembly
*2 Airbag Sensor Assembly
*3 Main Body ECU (Multiplex Network Body ECU)

CAUTION / NOTICE / HINT

Note


  • After turning the ignition 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

  • Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.*


    • *: w/ Smart Entry and Start System

  • The vehicle battery supplies power to the main body ECU (multiplex network body ECU) via the door control battery. Therefore, before performing this troubleshooting procedure, make sure to perform an on-vehicle inspection to confirm that the main body ECU (multiplex network body ECU) power source circuit is normal.*

    Click here


    • *: w/ Door Control Battery

PROCEDURE


  1. CHECK DTC OUTPUT


    1. Clear the DTCs.


      Body Electrical > Main Body > Clear DTCs
    2. Recheck for DTCs.


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

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


    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 ignition switch to ON with the airbag sensor assembly connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    2. Disconnect the K73 airbag sensor assembly connector.

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

    4. B0086ESC01
      *a

      Component without harness connected

      (Airbag Sensor Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      K73-25 (GSW) - Body ground Ignition switch ON 4.3 to 5.5 V
      Result
      Proceed to
      OK
      NG

    OK
    NG
  3. CHECK HARNESS AND CONNECTOR (AIRBAG SENSOR ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK 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.

    2. Disconnect the 3A instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K73-25 (GSW) - 3A-7 Always Below 1 Ω
      3A-7 or K73-25 (GSW) - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG
    OK
  4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

      Click here

    2. Remove the main body ECU (multiplex network body ECU).

      B00893RC02
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      MB-24 (GSW) - 3A-7 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK
    NG