PRE-CRASH SAFETY SYSTEM, Diagnostic DTC:B2075

DTC Code DTC Name
B2075 Passenger Side Seat Belt Buckle Switch Circuit Malfunction

DESCRIPTION

This DTC is stored when there is a short or open in the front seat inner belt buckle switch circuit (for passenger side).

DTC No. DTC Detection Condition Trouble Area
B2075 Open or short in front seat inner belt (buckle switch) circuit

  • CAN communication system

  • Front seat inner belt (for passenger side)

  • Seat belt control ECU

  • Wire harness or connector

WIRING DIAGRAM

A003X5XE05

INSPECTION PROCEDURE

Tech Tips

This circuit uses CAN communication. Therefore, be sure to check that the CAN communication system is normal before performing inspection Click here.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (FRONT SEAT INNER BELT - SEAT BELT CONTROL ECU)


    1. Disconnect the front seat inner belt connector.

    2. Disconnect the seat belt control ECU connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard Resistance
      for RHD
      Tester Connection Condition Specified Condition
      H7-5 (PBK+) - P25-5 (LBE+) Always Below 1 Ω
      H7-6 (PBK-) - P25-4 (LBE-) Always Below 1 Ω
      H7-5 (PBK+) or P25-5 (LBE+) - Body ground Always 10 kΩ or higher
      H7-6 (PBK-) or P25-4 (LBE-) - Body ground Always 10 kΩ or higher
      for LHD
      Tester Connection Condition Specified Condition
      H7-5 (PBK+) - Q20-5 (RBE+) Always Below 1 Ω
      H7-6 (PBK-) - Q20-4 (RBE-) Always Below 1 Ω
      H7-5 (PBK+) or Q20-5 (RBE+) - Body ground Always 10 kΩ or higher
      H7-6 (PBK-) or Q20-4 (RBE-) - Body ground Always 10 kΩ or higher

    4. Reconnect the seat belt control ECU connector.

    5. Reconnect the front seat inner belt connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT SEAT INNER BELT - SEAT BELT CONTROL ECU)

    OK

  2. CHECK SEAT BELT CONTROL ECU


    1. A003Z6PE04
      Text in Illustration
      *1 Seat Belt Control ECU

      Fasten the passenger side seat belt.

    2. Turn the power switch on (IG).

    3. Using an oscilloscope, check the waveform of the seat belt control ECU between the connector terminals.

      Tech Tips

      Voltage is only output for 10 ms of a 100 ms cycle.

      Item Contents
      Terminal

      H7-5 (PBK+)

      H7-6 (PBK-)
      Tool setting 2V/DIV, 20ms/DIV
      Vehicle Condition Power switch on (IG)
      OK
      Approximately 5 V

    NG

    REPLACE FRONT SEAT INNER BELT (for Passenger Side) Click here

    OK

    REPLACE SEAT BELT CONTROL ECU Click here