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HOMESERVICE MANUALSTOYOTA20254RUNNER SR5, 4WDREPAIR AND DIAGNOSIS (SINGLE PAGE)RESTRAINTSAIR BAG, SRSOCCUPANT CLASSIFICATION SYSTEM - DIAGNOSTIC CODES, SYMPTOM TESTS & CIRCUIT TESTSOCCUPANT CLASSIFICATION SYSTEMDTC B00C2-86: PASSENGER SEAT OCCUPANT CLASSIFICATION SENSOR "C" SIGNAL (SOME CIRCUIT QUANTITY, REPORTED VIA SERIAL DATA) INVALID [12/2024 - ]PROCEDURE
2025 Toyota 4Runner SR5, 4WD

DTC B00C2-86: Passenger Seat Occupant Classification Sensor "C" Signal (some circuit quantity, reported via serial data) Invalid [12/2024 - ]: Procedure

2025 Toyota 4Runner SR5, 4WDSECTION Procedure
  1. CHECK DTC 
    1. Check the DTCs.

      Body Electrical > SRS Airbag > Trouble Codes 

      Result

      Result Proceed to
      B00C0-86 is output A
      B00C2-86 is output B
      B00C0-86 and B00C2-86 are output C
      B00C0-86 and B00C2-86 are not output D

      HINT: 

      Codes other than DTCs B00C0-86 and B00C2-86 may be output at this time, but they are not related to this check.

    Result: 

    B 

    See step  5

    Result: 

    C 

    See step  8

    Result: 

    D 

    USE SIMULATION METHOD TO CHECK 

    Refer to METHOD TO SIMULATE PROBLEM SYMPTOMS [12/2024 - ]

    Result: 

    A 

    See step  2

  2. CHECK CONNECTION OF CONNECTORS 

    Pre-procedure1

    • Turn the ignition switch off.
    • Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 60 seconds.
    • Check that the connectors are properly connected to the airbag ECU assembly and front seat adjuster assembly RH (front occupant classification sensor LH).

      OK

      The connectors are properly connected.

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    CONNECT CONNECTORS PROPERLY 

    Result: 

    OK 

    See step  3

  3. CHECK CONNECTORS 

    Pre-procedure1

    • Disconnect the airbag ECU assembly connector.
      GTY984871Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Seat Adjuster Assembly RH (Front Occupant Classification Sensor LH)
      *2 Airbag ECU Assembly
      *3 Wire Harness
    • Disconnect the front seat adjuster assembly RH (front occupant classification sensor LH) connector.
    • Check that the terminals of the connectors are not deformed or damaged.

      OK

      The terminals are not deformed or damaged.

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (AIRBAG ECU ASSEMBLY - FRONT SEAT ADJUSTER ASSEMBLY RH) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      S3-32 (SIG) - e10-2 (SIG1) Always Below 1 Ω Ω
      GTY1273794Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Seat Adjuster Assembly RH
      *2 Airbag ECU Assembly
      *3 Wire Harness
      *a Front view of wire harness connector
      (to Airbag ECU Assembly)
      *b Front view of wire harness connector
      (to Front Seat Adjuster Assembly RH (Front Occupant Classification Sensor LH))

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FRONT SEAT ADJUSTER ASSEMBLY RH 

    for Manual Seat: Refer to REMOVAL [12/2024 - ]

    for Power Seat: Refer to REMOVAL [12/2024 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. CHECK CONNECTION OF CONNECTORS 

    Pre-procedure1

    • Turn the ignition switch off.
    • Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 60 seconds.
    • Check that the connectors are properly connected to the airbag ECU assembly and front seat adjuster assembly RH (rear occupant classification sensor LH).

      OK

      The connectors are properly connected.

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    CONNECT CONNECTORS PROPERLY 

    Result: 

    OK 

    See step  6

  6. CHECK CONNECTORS 

    Pre-procedure1

    • Disconnect the airbag ECU assembly connector.
      GTY984871Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Seat Adjuster Assembly RH (Rear Occupant Classification Sensor LH)
      *2 Airbag ECU Assembly
      *3 Wire Harness
    • Disconnect the front seat adjuster assembly RH (rear occupant classification sensor LH) connector.
    • Check that the terminals of the connectors are not deformed or damaged.

      OK

      The terminals are not deformed or damaged.

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (AIRBAG ECU ASSEMBLY - FRONT SEAT ADJUSTER ASSEMBLY RH) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      S3-32 (SIG) - e11-2 (SIG3) Always Below 1 Ω Ω
      GTY1273793Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Seat Adjuster Assembly RH
      *2 Airbag ECU Assembly
      *3 Wire Harness
      *a Front view of wire harness connector
      (to Airbag ECU Assembly)
      *b Front view of wire harness connector
      (to Front Seat Adjuster Assembly RH (Rear Occupant Classification Sensor LH))

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FRONT SEAT ADJUSTER ASSEMBLY RH 

    for Manual Seat: Refer to REMOVAL [12/2024 - ]

    for Power Seat: Refer to REMOVAL [12/2024 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  8. CHECK CONNECTION OF CONNECTORS 

    Pre-procedure1

    • Turn the ignition switch off.
    • Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 60 seconds.
    • Check that the connectors are properly connected to the airbag ECU assembly and front seat adjuster assembly RH.

      OK

      The connectors are properly connected.

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    CONNECT CONNECTORS PROPERLY 

    Result: 

    OK 

    See step  9

  9. CHECK CONNECTORS 

    Pre-procedure1

    • Disconnect the airbag ECU assembly connector.
      GTY985316Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Seat Adjuster Assembly RH
      *2 Airbag ECU Assembly
      *3 Wire Harness
    • Disconnect the front seat adjuster assembly RH connector.
    • Check that the terminals of the connectors are not deformed or damaged.

      OK

      The terminals are not deformed or damaged.

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (AIRBAG ECU ASSEMBLY - FRONT SEAT ADJUSTER ASSEMBLY RH) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      S3-32 (SIG) - e10-2 (SIG1) Always Below 1 Ω Ω
      S3-32 (SIG) - e11-2 (SIG3) Always Below 1 Ω Ω
      GTY1272889Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Seat Adjuster Assembly RH
      *2 Airbag ECU Assembly
      *3 Wire Harness
      *a Front view of wire harness connector
      (to Airbag ECU Assembly)
      *b Front view of wire harness connector
      (to Front Seat Adjuster Assembly RH (Front Occupant Classification Sensor LH))
      *c Front view of wire harness connector
      (to Front Seat Adjuster Assembly RH (Rear Occupant Classification Sensor LH))

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  11

  11. CHECK HARNESS AND CONNECTOR (AIRBAG ECU ASSEMBLY - FRONT SEAT ADJUSTER ASSEMBLY RH) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      S3-32 (SIG) - Other terminals and body ground Always 10 kΩ or higher kΩ
      e10-2 (SIG1) - Other terminals and body ground Always 10 kΩ or higher kΩ
      e11-2 (SIG3) - Other terminals and body ground Always 10 kΩ or higher kΩ
      GTY1272889Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Seat Adjuster Assembly RH
      *2 Airbag ECU Assembly
      *3 Wire Harness
      *a Front view of wire harness connector
      (to Airbag ECU Assembly)
      *b Front view of wire harness connector
      (to Front Seat Adjuster Assembly RH (Front Occupant Classification Sensor LH))
      *c Front view of wire harness connector
      (to Front Seat Adjuster Assembly RH (Rear Occupant Classification Sensor LH))

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  12

  12. CHECK HARNESS AND CONNECTOR (AIRBAG ECU ASSEMBLY - FRONT SEAT ADJUSTER ASSEMBLY RH) 

    Pre-procedure1

    • Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
    • Turn the ignition switch to ON.
    • Measure the voltage according to the value(s) in the table below.
      GTY1272889Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Seat Adjuster Assembly RH
      *2 Airbag ECU Assembly
      *3 Wire Harness
      *a Front view of wire harness connector
      (to Airbag ECU Assembly)
      *b Front view of wire harness connector
      (to Front Seat Adjuster Assembly RH (Front Occupant Classification Sensor LH))
      *c Front view of wire harness connector
      (to Front Seat Adjuster Assembly RH (Rear Occupant Classification Sensor LH))

      Standard Voltage

      Tester Connection Condition Specified Condition Result
      S3-32 (SIG) - Body ground Ignition switch ON Below 1 V V
      e10-2 (SIG1) - Body ground Ignition switch ON Below 1 V V
      e11-2 (SIG3) - Body ground Ignition switch ON Below 1 V V

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    OK 

    REPLACE AIRBAG ECU ASSEMBLY 

    Refer to REMOVAL [12/2024 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

RENDER: 1.0x

NO RELATED

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