SEAT BELT WARNING SYSTEM Rear Seat Belt Warning Light Malfunction

DESCRIPTION

The main body ECU (multiplex network body ECU) detects whether either rear door is open or closed based on the condition of the left and right courtesy light switches and then sends the rear door status signal to the combination meter assembly. The combination meter assembly detects the rear seat belt state. The rear seat belt warning lights on the telltale light assembly illuminate or turn off in accordance with the rear door state, vehicle speed and rear seat belt state.

WIRING DIAGRAM

B0042S4E01

CAUTION / NOTICE / HINT

Note


  • The seat belt warning system uses the CAN communication system. First, confirm that there are no malfunctions in the CAN communication system. Refer to the How to Proceed with Troubleshooting procedure.

    Click here

  • Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE


  1. READ VALUE USING GTS (REAR DOOR COURTESY LIGHT 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
      RR Door Courtesy SW Rear door courtesy light switch assembly (for RH) ON or OFF

      ON: Rear door RH open

      OFF: Rear door RH closed

      		 -
      RL Door Courtesy SW Rear door courtesy light switch assembly (for LH) ON or OFF

      ON: Rear door LH open

      OFF: Rear door LH closed

      		 -

      Body Electrical > Main Body > Data List
      Tester Display
      RR Door Courtesy SW
      RL Door Courtesy SW
      OK
      The GTS display changes correctly in response to the rear door condition.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO LIGHTING SYSTEM Click here

    OK

  2. CHECK REAR SEAT BELT WARNING


    1. B00451YC01
      *1 Rear Seat Belt Warning Light (Telltale Light Assembly)
      *a LH
      *b Center
      *c RH

      Check the rear seat belt warning function.

      Result
      Result Proceed to
      The rear seat belt warning lights operate normally A
      The rear seat belt warning lights (all seats) do not operate normally B
      The rear seat belt warning light (RH) does not operate normally C
      The rear seat belt warning light (center) does not operate normally D
      The rear seat belt warning light (LH) does not operate normally E

    A

    USE SIMULATION METHOD TO CHECK Click here

    C

    READ VALUE USING GTS (REAR SEAT BELT BUCKLE SWITCH (FOR RH)) Click here

    D

    READ VALUE USING GTS (REAR SEAT BELT BUCKLE SWITCH (FOR CENTER)) Click here

    E

    READ VALUE USING GTS (REAR SEAT BELT BUCKLE SWITCH (FOR LH)) Click here

    B

  3. PERFORM ACTIVE TEST USING GTS (REAR SEAT BELT WARNING LIGHT)


    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
      Rear Seat Belt Rear seat belt warning light OFF/ON -

      Body Electrical > Combination Meter > Active Test
      Tester Display
      Rear Seat Belt
      Result
      Result Proceed to
      The rear seat belt warning lights do not operate normally A
      The rear seat belt warning lights operate normally B

    B

    REPLACE COMBINATION METER ASSEMBLY except Sedan: Click here
    REPLACE COMBINATION METER ASSEMBLY for Sedan: Click here

    A

  4. CHECK HARNESS AND CONNECTOR (BATTERY - TELLTALE LIGHT ASSEMBLY)


    1. Disconnect the E48 telltale light assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      E48-10 (IG+) - Body ground Ignition switch ON 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (TELLTALE LIGHT ASSEMBLY - COMBINATION METER ASSEMBLY)


    1. Reconnect the E48 telltale light assembly connector.

    2. Disconnect the E46 combination meter assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      E46-1 (RLMT) - Body ground Ignition switch ON 11 to 14 V
      E46-2 (RCMT) - Body ground Ignition switch ON 11 to 14 V
      E46-3 (RRMT) - Body ground Ignition switch ON 11 to 14 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE COMBINATION METER ASSEMBLY except Sedan: Click here
    REPLACE COMBINATION METER ASSEMBLY for Sedan: Click here

    NG

    REPLACE TELLTALE LIGHT ASSEMBLY except Sedan: Click here
    REPLACE TELLTALE LIGHT ASSEMBLY for Sedan: Click here

  6. READ VALUE USING GTS (REAR SEAT BELT BUCKLE SWITCH (FOR RH))


    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 / Data List.

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


      Body Electrical > Combination Meter > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      2nd-Row Seatbelt Buckle (R) Rear RH seat belt buckle switch signal ON or OFF

      OFF: Rear RH seat belt fastened

      ON: Rear RH seat belt not fastened

      		 -

      Body Electrical > Combination Meter > Data List
      Tester Display
      2nd-Row Seatbelt Buckle (R)
      Result
      Result Proceed to
      ON or OFF does not appear on the GTS screen according to the rear seat belt condition A
      ON or OFF appears on the GTS screen according to the rear seat belt condition B

    B

    PERFORM ACTIVE TEST USING GTS (REAR SEAT BELT WARNING LIGHT) Click here

    A

  7. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - REAR SEAT INNER WITH CENTER BELT ASSEMBLY RH - BODY GROUND)


    1. Disconnect the E46 combination meter assembly connector.

    2. Disconnect the L38 rear seat inner with center belt assembly RH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E46-26 (RRSB) - L38-1 (RBR+) Always Below 1 Ω
      E46-26 (RRSB) - Body ground Always 10 kΩ or higher
      L38-2 (RBR-) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE REAR SEAT INNER WITH CENTER BELT ASSEMBLY RH except Sedan: Click here
    REPLACE REAR SEAT INNER WITH CENTER BELT ASSEMBLY RH for Sedan: Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  8. PERFORM ACTIVE TEST USING GTS (REAR SEAT BELT WARNING LIGHT)


    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
      Rear Seat Belt Rear seat belt warning light OFF/ON -

      Body Electrical > Combination Meter > Active Test
      Tester Display
      Rear Seat Belt
      Result
      Result Proceed to
      The rear seat belt warning light does not operate normally A
      The rear seat belt warning light operates normally B

    B

    REPLACE COMBINATION METER ASSEMBLY except Sedan: Click here
    REPLACE COMBINATION METER ASSEMBLY for Sedan: Click here

    A

  9. CHECK HARNESS AND CONNECTOR (TELLTALE LIGHT ASSEMBLY - COMBINATION METER ASSEMBLY)


    1. Disconnect the E46 combination meter assembly connector.

    2. Disconnect the E48 telltale light assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E46-3 (RRMT) - E48-3 (RRID) Always Below 1 Ω
      E46-3 (RRMT) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE TELLTALE LIGHT ASSEMBLY except Sedan: Click here
    REPLACE TELLTALE LIGHT ASSEMBLY for Sedan: Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  10. READ VALUE USING GTS (REAR SEAT BELT BUCKLE SWITCH (FOR CENTER))


    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 / Data List.

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


      Body Electrical > Combination Meter > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      2nd-Row Seatbelt Buckle (C) Rear center seat belt buckle switch signal ON or OFF

      OFF: Rear center seat belt fastened

      ON: Rear center seat belt not fastened

      		 -

      Body Electrical > Combination Meter > Data List
      Tester Display
      2nd-Row Seatbelt Buckle (C)
      Result
      Result Proceed to
      ON or OFF does not appear on the GTS screen according to the rear seat belt condition A
      ON or OFF appears on the GTS screen according to the rear seat belt condition B

    B

    PERFORM ACTIVE TEST USING GTS (REAR SEAT BELT WARNING LIGHT) Click here

    A

  11. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - REAR SEAT INNER WITH CENTER BELT ASSEMBLY LH (FOR CENTER) - BODY GROUND)


    1. Disconnect the E46 combination meter assembly connector.

    2. Disconnect the L39 rear seat inner with center belt assembly LH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E46-25 (RCSB) - L39-1 (CBR+) Always Below 1 Ω
      E46-25 (RCSB) - Body ground Always 10 kΩ or higher
      L39-2 (CBR-) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE REAR SEAT INNER WITH CENTER BELT ASSEMBLY LH except Sedan: Click here
    REPLACE REAR SEAT INNER WITH CENTER BELT ASSEMBLY LH for Sedan: Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  12. PERFORM ACTIVE TEST USING GTS (REAR SEAT BELT WARNING LIGHT)


    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
      Rear Seat Belt Rear seat belt warning light OFF/ON -

      Body Electrical > Combination Meter > Active Test
      Tester Display
      Rear Seat Belt
      Result
      Result Proceed to
      The rear seat belt warning light does not operate normally A
      The rear seat belt warning light operates normally B

    B

    REPLACE COMBINATION METER ASSEMBLY except Sedan: Click here
    REPLACE COMBINATION METER ASSEMBLY for Sedan: Click here

    A

  13. CHECK HARNESS AND CONNECTOR (TELLTALE LIGHT ASSEMBLY - COMBINATION METER ASSEMBLY)


    1. Disconnect the E46 combination meter assembly connector.

    2. Disconnect the E48 telltale light assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E46-2 (RCMT) - E48-2 (RCID) Always Below 1 Ω
      E46-2 (RCMT) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE TELLTALE LIGHT ASSEMBLY except Sedan: Click here
    REPLACE TELLTALE LIGHT ASSEMBLY for Sedan: Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  14. READ VALUE USING GTS (REAR SEAT BELT BUCKLE SWITCH (FOR LH))


    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 / Data List.


      Body Electrical > Combination Meter > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      2nd-Row Seatbelt Buckle (L) Rear LH seat belt buckle switch signal ON or OFF

      OFF: Rear LH seat belt fastened

      ON: Rear LH seat belt not fastened

      		 -

      Body Electrical > Combination Meter > Data List
      Tester Display
      2nd-Row Seatbelt Buckle (L)

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

      Result
      Result Proceed to
      ON or OFF does not appear on the GTS screen according to the rear seat belt condition A
      ON or OFF appears on the GTS screen according to the rear seat belt condition B

    B

    PERFORM ACTIVE TEST USING GTS (REAR SEAT BELT WARNING LIGHT) Click here

    A

  15. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - REAR SEAT INNER WITH CENTER BELT ASSEMBLY LH (FOR LH) - BODY GROUND)


    1. Disconnect the E46 combination meter assembly connector.

    2. Disconnect the L39 rear seat inner with center belt assembly LH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E46-24 (RLSB) - L39-3 (LBR+) Always Below 1 Ω
      E46-24 (RLSB) - Body ground Always 10 kΩ or higher
      L39-4 (LBR-) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE REAR SEAT INNER WITH CENTER BELT ASSEMBLY LH except Sedan: Click here
    REPLACE REAR SEAT INNER WITH CENTER BELT ASSEMBLY LH for Sedan: Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  16. PERFORM ACTIVE TEST USING GTS (REAR SEAT BELT WARNING LIGHT)


    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
      Rear Seat Belt Rear seat belt warning light OFF/ON -

      Body Electrical > Combination Meter > Active Test
      Tester Display
      Rear Seat Belt
      Result
      Result Proceed to
      The rear seat belt warning light does not operate normally A
      The rear seat belt warning light operates normally B

    B

    REPLACE COMBINATION METER ASSEMBLY except Sedan: Click here
    REPLACE COMBINATION METER ASSEMBLY for Sedan: Click here

    A

  17. CHECK HARNESS AND CONNECTOR (TELLTALE LIGHT ASSEMBLY - COMBINATION METER ASSEMBLY)


    1. Disconnect the E46 combination meter assembly connector.

    2. Disconnect the E48 telltale light assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E46-1 (RLMT) - E48-1 (RLID) Always Below 1 Ω
      E46-1 (RLMT) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE TELLTALE LIGHT ASSEMBLY except Sedan: Click here
    REPLACE TELLTALE LIGHT ASSEMBLY for Sedan: Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR