SEAT BELT WARNING SYSTEM Driver Side Seat Belt Warning Light does not Operate

DESCRIPTION

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


WIRING DIAGRAM

A002QK8E09

PROCEDURE


  1. CHECK FOR DTC (CAN COMMUNICATION SYSTEM)


    1. Check if a CAN communication system DTC is output.

      Result
      Result Proceed to
      DTC is not output A
      CAN system DTC is output B

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  2. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (DRIVER SIDE SEAT BELT WARNING LIGHT)


    1. Select the Active Test, use the intelligent tester to generate a control command, and then check that the driver side seat belt warning light turns on/off Click here.

      Combination Meter
      Item Test Part Control Range Diagnostic Note
      Driver Side Seat Belt Driver side seat belt warning light ON/OFF Confirm that the vehicle is stopped and the engine is idling.
      OK
      Driver side seat belt warning light condition can be switched by Active Test.

    NG

    REPLACE COMBINATION METER Click here

    OK

  3. READ VALUE USING INTELLIGENT TESTER (DRIVER SIDE SEAT BELT BUCKLE SWITCH)


    1. Check the Data List for proper functioning of the driver side seat belt buckle switch Click here.

      Main Body
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      D Seat Buckle SW Driver side seat belt buckle signal / ON or OFF

      ON: Driver side seat belt fastened

      OFF: Driver side seat belt unfastened

      		 -
      OK
      The display is as specified in the normal condition column.

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  4. INSPECT FRONT SEAT INNER BELT ASSEMBLY


    1. A002ONXE05

      Remove the front seat inner belt Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2 (+) - 1 (E) Driver side seat belt fastened 10 kΩ or higher
      Driver side seat belt unfastened Below 1 Ω

    NG

    REPLACE FRONT SEAT INNER BELT ASSEMBLY Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (FRONT SEAT INNER BELT - MAIN BODY ECU AND BODY GROUND)


    1. A002NTZE01
      Text in Illustration
      *1 for LHD
      *2 for RHD
      *3

      Front view of wire harness connector

      (to Front Seat Inner Belt)
      *4

      Front view of wire harness connector

      (to Main Body ECU)

      Disconnect the N7*1 or O4*2 front seat inner belt connector.


      • *1: for LHD

      • *2: for RHD

    2. Disconnect the H79 ECU connector.

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

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      N7-2 (+) - H79-26 (DBKL) Always Below 1 Ω
      N7-1 (E) - Body ground
      N7-2 (+) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      O4-2 (+) - H79-26 (DBKL) Always Below 1 Ω
      O4-1 (E) - Body ground
      O4-2 (+) - Body ground Always 10 kΩ or higher

    OK

    REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR