LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2023 >> LS 500h >> Repair and Diagnosis >> Restraints >> Air Bag, SRS >> Airbag System (W/ Advanced Park) - Diagnostic Codes (4 Of 6) >> AIRBAG SYSTEM (w/ Advanced Park) >> DTC B0053-00: Passenger Seat Belt Sensor Circuit Undetermined Failure [11/2021 - 10/2023] >> Procedure

DTC B0053-00: Passenger Seat Belt Sensor Circuit Undetermined Failure [11/2021 - 10/2023]: Procedure

  1. CHECK CONNECTION OF CONNECTORS 

    Pre-procedure1

    1. Turn the power switch off.
    2. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 60 seconds.

      Procedure1

    3. Check that the connectors are properly connected to the airbag ECU assembly and rear seat inner belt assembly LH.

      OK

      The connectors are properly connected.

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. None

    Result: 

    NG 

    CONNECT CONNECTORS PROPERLY 

    Result: 

    OK 

    See step  2

  2. CHECK CONNECTORS 

    Pre-procedure1

    1. Disconnect the airbag ECU assembly connector.
      GTY871790Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Rear Seat Inner Belt Assembly LH
      *2 Airbag ECU Assembly
      *3 Wire Harness
    2. Disconnect the rear seat inner belt assembly LH connector.

      Procedure1

    3. Check that the connectors (on the airbag ECU assembly side and rear seat inner belt assembly LH side) are not damaged.

      OK

      The terminals of the connectors are not deformed or damaged.

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. INSPECT REAR SEAT INNER BELT ASSEMBLY LH 

    Pre-procedure1

    1. Remove the rear seat inner belt assembly LH.

      Refer to REMOVAL [11/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 10/2023]

      Procedure1

    2. Inspect the rear seat inner belt assembly LH.
      GTY1088053Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Rear Seat Inner Belt Assembly LH *2 Battery
      *a Component without harness connected
      (Rear Seat Inner Belt Assembly LH)      		 *b Tester

      Standard Current

      Tester Connection Condition Specified Condition
      Tester positive (+) - 2
      Tester negative (-) - Battery negative (-)      		 Seat belt fastened 12.0 to 18.0 mA
      Seat belt not fastened 4.0 to 7.0 mA

      Post-procedure1

    3. None

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE REAR SEAT INNER BELT ASSEMBLY LH. Refer to  REMOVAL [11/2021 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023] 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT TO GROUND IN THE CIRCUIT) 
    1. Measure the resistance according to the value(s) in the table below.
      GTY1087856Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Rear Seat Inner Belt Assembly LH
      *2 Airbag ECU Assembly
      *3 Wire Harness
      *a Front view of wire harness connector
      (to Rear Seat Inner Belt Assembly LH)
      *b Front view of wire harness connector
      (to Airbag ECU Assembly)

      Standard Resistance

      Tester Connection Condition Specified Condition
      R50-1 - Body ground Always 1 MΩ or higher
      R50-2 - Body ground Always 1 MΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (CHECK FOR OPEN IN THE CIRCUIT) 

    Pre-procedure1

    1. Using a service wire, connect terminals 23 (LBR+) and 24 (GNDL) of connector B.
      NOTE:

      Do not forcibly insert the service wire into the terminals of the connector when connecting a service wire.

      GTY1088003Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Rear Seat Inner Belt Assembly LH
      *2 Airbag ECU Assembly
      *3 Wire Harness
      *4 Service Wire
      *a Front view of wire harness connector
      (to Rear Seat Inner Belt Assembly LH)
      *b Front view of wire harness connector
      (to Airbag ECU Assembly)

      Procedure1

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      R50-1 - R50-2 Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    3. Disconnect the service wire from connector B.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT TO +B IN THE CIRCUIT) 

    Pre-procedure1

    1. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
      GTY1087856Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Rear Seat Inner Belt Assembly LH
      *2 Airbag ECU Assembly
      *3 Wire Harness
      *a Front view of wire harness connector
      (to Rear Seat Inner Belt Assembly LH)
      *b Front view of wire harness connector
      (to Airbag ECU Assembly)
    2. Turn the power switch on (IG).

      Procedure1

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

      Standard Voltage

      Tester Connection Condition Specified Condition
      R50-1 - Body ground Power switch on (IG) Below 1 V
      R50-2 - Body ground Power switch on (IG) Below 1 V

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Turn the power switch off.
    5. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 60 seconds.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CLEAR DTC 
    1. Connect the airbag ECU assembly connector.
      GTY972490Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Rear Seat Inner Belt Assembly LH
      *2 Airbag ECU Assembly
      *3 Wire Harness
    2. Connect the rear seat inner belt assembly LH connector.
    3. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
    4. Turn the power switch on (IG), and wait for at least 60 seconds.
    5. Clear the DTCs stored in memory.

      Body Electrical > SRS Airbag > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  8

  8. CHECK DTC 

    Pre-procedure1

    1. Turn the power switch off.
    2. Turn the power switch on (IG), and wait for at least 60 seconds.

      Procedure1

    3. Check for DTCs.

      Body Electrical > SRS Airbag > Trouble Codes 

      Result

      Result  Proceed to
      B0053-00 is not output A
      B0053-00 is output B

      Post-procedure1

    4. None

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - 10/2022]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2022 - 10/2023] 

    Result: 

    B 

    REPLACE AIRBAG ECU ASSEMBLY. Refer to  REMOVAL [11/2021 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023] 

scientia non olet · About LEMON Manuals