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Home >> Toyota >> 2008 >> Corolla LE, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 44 (Supplemental Restraint System) >> Occupant Classification System >> DTC B1780 Front Occupant Classification Sensor LH Circuit Malfunction >> Inspection Procedure

Inspection Procedure

WARNING: This page is about a different car, the 2007 Toyota Camry Solara. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

  1. CHECK DTC 
    1. Turn the ignition switch to the ON position.
    2. Clear the DTCs stored in memory (See DIAGNOSIS SYSTEM  ).

      HINT:

      First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.

    3. Turn the ignition switch to the LOCK position.
    4. Turn the ignition switch to the ON position.
    5. Check the DTCs (See DIAGNOSIS SYSTEM  ).

      OK: DTC B1780 is not output. 

      HINT:

      Codes other than DTC B1780 may be output at this time, but they are not related to this check.

    OK: USE SIMULATION METHOD TO CHECK 

    NG: Go to Next Step 

  2. CHECK CONNECTION OF CONNECTORS 
    1. Turn the ignition switch to the LOCK position.
    2. Disconnect the negative (-) terminal cable from the battery.
    3. Check that the connectors are properly connected to the occupant classification ECU and the front occupant classification sensor LH.

      OK: The connectors are connected. 

    NG: CONNECT CONNECTOR, THEN GO TO STEP  1

    OK: Go to Next Step 

  3. CHECK FLOOR WIRE NO. 2 (SHORT TO B+) 
    Fig 1: Checking Floor Wire No. 2 (Short To B+)
    G05131633Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the connectors from the occupant classification ECU and the front occupant classification sensor LH.
    2. Connect the negative (-) terminal cable to the battery.
    3. Turn the ignition switch to the ON position.
    4. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester connection Condition Specified condition
      O3-1(SGD1)- Body ground Ignition switch ON Below 1 V
      O3-7 (SIG1)- Body ground Ignition switch ON Below 1 V
      O3-11 (SVC1)- Body ground Ignition switch ON Below 1V

    NG: REPAIR OR REPLACE FLOOR WIRE NO. 2 

    OK: Go to Next Step 

  4. CHECK FLOOR WIRE NO. 2 (OPEN) 
    Fig 2: Checking Floor Wire No. 2 (Open)
    G05131634Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the ignition switch to the LOCK position.
    2. Disconnect the negative (-) terminal cable from the battery.
    3. Using a service wire, connect O4-1 (SVC1) and O4-3 (SGD1), and connect O4-2 (SIG1) and O4-3 (SGD1) of connector "C".
      NOTE: Do not forcibly insert a service wire into the terminals of the connector when connecting.
    4. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester connection Condition Specified condition
      O3-7 (SIG1) - O3-1 (SGD1) Always Below 1 Ω
      O3-11 {SVC1) - O3-1 (SGD1) Always Below 1 Ω

    NG: REPAIR OR REPLACE FLOOR WIRE NO. 2 

    OK: Go to Next Step 

  5. CHECK FLOOR WIRE NO. 2 (SHORT) 
    Fig 3: Checking Floor Wire No. 2 (Short)
    G05131633Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the service wire from connector "C".
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester connection Condition Specified condition
      O3-7 (SIG1) -O3-1 (SGD1) Always 1 MΩ or higher
      O3-11 (SVC1)-O3-1 (SGD1) Always 1 MΩ or higher
      O3-7 (SIG1)-O3-11 (SVC1) Always 1 MΩ or higher

    NG: REPAIR OR REPLACE FLOOR WIRE NO. 2 

    OK: Go to Next Step 

  6. CHECK FLOOR WIRE NO. 2 (SHORT TO GROUND) 
    Fig 4: Checking Floor Wire No. 2 (Short To Ground)
    G05131633Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester connection Condition Specified condition
      O3-1 (SGD1) - Body ground Always 1 MΩ or higher
      O3-7 (SIG1) - Body ground Always 1 MΩ or higher
      O3-11 (SVC1) - Body ground Always 1 MΩ or higher

    NG: REPAIR OR REPLACE FLOOR WIRE NO. 2 

    OK: Go to Next Step 

  7. CHECK DTC 
    1. Connect the connectors to the occupant classification ECU and the front occupant classification sensor LH.
    2. Connect the negative (-) terminal cable to the battery.
    3. Turn the ignition switch to the ON position.
    4. Clear the DTCs stored in memory (See DIAGNOSIS SYSTEM  ).

      HINT:

      First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.

    5. Turn the ignition switch to the LOCK position.
    6. Turn the ignition switch to the ON position.
    7. Check the DTCs (See DTC CHECK / CLEAR  ).

      OK: DTC B1780 is not output. 

      HINT:

      Codes other than DTC B1780 may be output at this time, but they are not related to this check.

    OK: USE SIMULATION METHOD TO CHECK 

    NG: Go to Next Step 

  8. REPLACE OCCUPANT CLASSIFICATION ECU 
    1. Turn the ignition switch to the LOCK position.
    2. Disconnect the negative (-) terminal cable from the battery.
    3. Replace the occupant classification ECU (See ON-VEHICLE INSPECTION  ).

      HINT:

      Perform the inspection using parts from a normal vehicle if possible.

  9. PERFORM ZERO POINT CALIBRATION 
    1. Connect the negative (-) terminal cable to the battery.
    2. Connect the intelligent tester to the DLC3.
    3. Turn the ignition switch to the ON position.
    4. Using the intelligent tester, perform "Zero Point calibration" (See INITIALIZATION  ).

      OK: The "COMPLETED" is displayed. 

    NG: Go to step  12

    OK: Go to Next Step 

  10. PERFORM SENSITIVITY CHECK 
    1. Using the intelligent tester, perform "Sensitivity check" (See INITIALIZATION  ).

      Standard: 27 to 33 kg (59.52 to 72.75 lb) 

    NG: Go to step  12

    OK: Go to Next Step 

  11. CHECK DTC 
    1. Connect the negative (-) terminal cable to the battery.
    2. Turn the ignition switch to the ON position.
    3. Clear the DTCs stored in memory (See DIAGNOSIS SYSTEM  ).

      HINT:

      First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.

    4. Turn the ignition switch to the LOCK position.
    5. Turn the ignition switch to the ON position.
    6. Check the DTCs (See DIAGNOSIS SYSTEM  ).

      OK: DTC B1780 is not output. 

      HINT:

      Codes other than DTC B1780 may be output at this time, but they are not related to this check.

    OK: END 

    NG: Go to Next Step 

  12. REPLACE FRONT SEAT ASSEMBLY RH 
    1. Turn the ignition switch to the LOCK position.
    2. Disconnect the negative (-) terminal cable from the battery.
    3. Replace the front seat assembly RH (See REMOVAL - MANUAL or REMOVAL - POWER ).
  13. PERFORM ZERO POINT CALIBRATION 
    1. Connect the negative (-) terminal cable to the battery.
    2. Connect the intelligent tester to the DLC3.
    3. Turn the ignition switch to the ON position.
    4. Using the intelligent tester, perform "Zero point calibration" (See INITIALIZATION  ).

      OK: The "COMPLETED" is display. 

  14. PERFORM SENSITIVITY CHECK 
    1. Using the intelligent tester, perform "Sensitivity check" (See INITIALIZATION  ).

      Standard: 27 to 33 kg (59.52 to 72.75 lb) 

    NEXT: END