SEAT BELT WARNING SYSTEM(w/o Occupant Classification System) Driver Side Seat Belt Warning Light does not Operate

DTC Code DTC Name
Driver Side Seat Belt Warning Light does not Operate

DESCRIPTION

When the ignition switch is turned to ON, the main body ECU (multiplex network body ECU) transmits front seat inner belt LH*1 (or RH*2) state signals to the combination meter assembly through the CAN. If the driver side seat belt is not fastened, the combination meter assembly blinks the front seat belt warning light. If the seat belt is fastened, the warning light goes off.

*1: for LHD

*2: for RHD

Tip:

The front seat belt warning light on the combination meter assembly is used for both the driver side seat and front passenger side seat.

WIRING DIAGRAM

C279307E01

CAUTION / NOTICE / HINT

Note:

The seat belt warning system uses a CAN communication system. Inspect the communication function by following How to Proceed with troubleshooting.

Troubleshoot the seat belt warning system after confirming that the communication system is functioning properly.

PROCEDURE

  1. READ VALUE USING GTS (D SEAT BELT BUCKLE SWITCH)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Main Body / Data List.

    5. Read the Data List according to the display on the GTS.

      Body Electrical > Main Body > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      D Seat Buckle SW

      Driver side seat belt buckle switch

      ON/OFF

      ON: Driver side seat belt fastened

      OFF: Driver side seat belt unfastened

      -

      Body Electrical > Main Body > Data List

      Tester Display

      D Seat Buckle SW

    Result

    Result

    Proceed to

    ON or OFF is displayed on the GTS screen according to the driver side seat belt condition

    A

    ON or OFF is not displayed normally on the GTS screen according to the driver side seat belt condition

    B

    B

    INSPECT FRONT SEAT INNER BELT ASSEMBLYClick here

    A
  2. PERFORM ACTIVE TEST USING GTS (DRIVER SIDE SEAT BELT)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Combination Meter / Active Test.

    5. Perform the Active Test according to the display on the GTS.

      Body Electrical > Combination Meter > Active Test

      Tester Display

      Measurement Item

      Control Range

      Diagnostic Note

      Driver Side Seat Belt

      Front seat belt warning light

      OFF/ON

      The current customize setting is displayed.

      Body Electrical > Combination Meter > Active Test

      Tester Display

      Driver Side Seat Belt

      OK

      The front seat belt warning light on the combination meter assembly operates normally.

    Result

    Proceed to

    OK

    NG

    NG

    REPLACE COMBINATION METER ASSEMBLY

    OK
  3. INSPECT FRONT SEAT INNER BELT ASSEMBLY

    1. Remove the front seat inner belt assembly.

      Click hereClick here

    2. Inspect the front seat inner belt assembly.

      Click hereClick here

    Result

    Proceed to

    OK

    NG

    NG

    REPLACE FRONT SEAT INNER BELT ASSEMBLY

    OK
  4. CHECK HARNESS AND CONNECTOR (FRONT SEAT INNER BELT ASSEMBLY - MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] AND BODY GROUND)

    1. Disconnect the N15*1,*3, N35*1,*4, M17*2,*3 or M31*2,*4 front seat inner belt assembly connector.

      • *1: for LHD

        *2: for RHD

        *3: for Power Seat

        *4: for Manual Seat

    2. Disconnect the A main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance

      for LHD, for Power Seat

      Tester Connection

      Condition

      Specified Condition

      N15-3 - A-18 (DBKL)

      Always

      Below 1 Ω

      N15-2 - Body ground

      N15-3 - Body ground

      Always

      10 kΩ or higher

      for LHD, for Manual Seat

      Tester Connection

      Condition

      Specified Condition

      N35-3 - A-18 (DBKL)

      Always

      Below 1 Ω

      N35-2 - Body ground

      N35-3 - Body ground

      Always

      10 kΩ or higher

      for RHD, for Power Seat

      Tester Connection

      Condition

      Specified Condition

      M17-3 - A-18 (DBKL)

      Always

      Below 1 Ω

      M17-2 - Body ground

      M17-3 - Body ground

      Always

      10 kΩ or higher

      for RHD, for Manual Seat

      Tester Connection

      Condition

      Specified Condition

      M31-3 - A-18 (DBKL)

      Always

      Below 1 Ω

      M31-2 - Body ground

      M31-3 - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG

    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    NG
  5. CHECK HARNESS AND CONNECTOR (FRONT SEAT INNER BELT ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

    1. Disconnect the N15*1,*3, N35*1,*4, M17*2,*3 or M31*2,*4 front seat inner belt assembly connector.

      • *1: for LHD

        *2: for RHD

        *3: for Power Seat

        *4: for Manual Seat

    2. Disconnect the 3E*1 or 3C*2 instrument panel junction block assembly connector.

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

      Standard Resistance

      for LHD, for Power Seat

      Tester Connection

      Condition

      Specified Condition

      N15-3 - 3E-34 (DBKL)

      Always

      Below 1 Ω

      for LHD, for Manual Seat

      Tester Connection

      Condition

      Specified Condition

      N35-3 - 3E-34 (DBKL)

      Always

      Below 1 Ω

      for RHD, for Power Seat

      Tester Connection

      Condition

      Specified Condition

      M17-3 - 3C-40 (DBKL)

      Always

      Below 1 Ω

      for RHD, for Manual Seat

      Tester Connection

      Condition

      Specified Condition

      M31-3 - 3C-40 (DBKL)

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG

    OK

    INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR