Inspection Procedure

HINT:

• If troubleshooting (wire harness inspection) is difficult to perform, remove the front passenger seat installation bolts to see the undersurface of the seat cushion.
• In the above case, hold the seat so that it does not fall down. Holding the seat for a long period of time may cause a problem, such as seat rail deformation. Hold the seat only as necessary.

1. CHECK FOR DTC 
   1. Turn the ignition switch ON.
   2. Clear the DTCs stored in the occupant classification ECU (see DTC CHECK / CLEAR  ).
   3. Clear the DTCs stored in the center airbag sensor (see ON-VEHICLE INSPECTION  ).
   4. Turn the ignition switch OFF.
   5. Turn the ignition switch ON.
   6. Check for the DTCs (see DTC CHECK / CLEAR  ).

      OK: 

      DTC B1790 is not output. 

      HINT:

      Codes other than DTC B1790 may be output at this time, but they are not related to this check.

   OK: USE SIMULATION METHOD TO CHECK (See  DIAGNOSIS SYSTEM   ) 

   NG: Go to next step 

2. CHECK CONNECTION OF CONNECTOR 
   1. Turn the ignition switch OFF.
   2. Disconnect the negative (-) terminal cable from the battery.
   3. Check that the connectors are properly connected to the occupant classification ECU and the center airbag sensor.

      OK: 

      Connectors are properly connected. 

   NG: CONNECT CONNECTORS PROPERLY 

   OK: Go to next step 

3. CHECK CONNECTOR 
   1. Disconnect the connectors from the center airbag sensor and the occupant classification ECU.
   2. Check that the connectors (on the center airbag sensor side and occupant classification ECU side) are not damaged.

      OK: 

      Connectors are not deformed or damaged. 

   NG: REPAIR OR REPLACE WIRE HARNESS 

   OK: Go to next step 

4. CHECK OCCUPANT CLASSIFICATION SYSTEM CIRCUIT 
   1. Connect the negative (-) terminal cable to the battery.
   2. Turn the ignition switch ON.
   3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION
      
      

      Tester Connection	Switch Condition	Specified Condition
      X5-11 (FSR+) - Body ground	Ignition switch ON	Below 1 V
      X5-12 (FSR-) - Body ground

   4. Turn the ignition switch OFF.
   5. Disconnect the negative (-) terminal cable from the battery.
   6. Using a service wire, connect terminals 16 (FSR+) and 24 (FSR-) of connector B.
      Fig 1: Checking Occupant Classification System Circuit

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: Do not forcibly insert the service wire into the terminals of the connector when connecting the wire.
   7. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION
      
      

      Tester Connection	Condition	Specified Condition
      X5-11 (FSR+) - X5-12 (FSR-)	Always	Below 1 Ω

   8. Disconnect the service wire from connector B.
   9. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION
      
      

      Tester Connection	Condition	Specified Condition
      X5-11(FSR+)-X5-12 (FSR-)	Always	1 MΩ or higher
      X5-11 (FSR+) - Body ground
      X5-12 (FSR-) - Body ground

   NG: Go to step  10

   OK: Go to next step 

5. CHECK FOR DTC 
   1. Connect the connectors to the occupant classification ECU and the center airbag sensor.
   2. Connect the intelligent tester (with CAN VIM) to the DLC3.
   3. Connect the negative (-) terminal cable to the battery.
   4. Turn the ignition switch ON.
   5. Clear the DTCs stored in the occupant classification ECU (see DTC CHECK / CLEAR  ).
   6. Clear the DTCs stored in the center airbag sensor (see DTC CHECK / CLEAR  ).
   7. Turn the ignition switch OFF.
   8. Turn the ignition switch ON.
   9. Using the intelligent tester, check for the DTCs of the occupant classification ECU (see DTC CHECK / CLEAR  ).

      OK: 

      DTC B1790 is not output. 

      HINT:

      Codes other than DTC B1790 may be output at this time, but they are not related to this check.

   OK: USE SIMULATION METHOD TO CHECK (See  DIAGNOSIS SYSTEM   ) 

   NG: Go to next step 

6. REPLACE OCCUPANT CLASSIFICATION ECU 
   1. Connect the intelligent tester (with CAN VIM) to the DLC3.
   2. Turn the ignition switch ON.
   3. Using the intelligent tester, save the ECU data from the ECU which has been installed on the vehicle (see REGISTRATION  ).
   4. Turn the ignition switch OFF.
   5. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
   6. Replace the occupant classification ECU (see REMOVAL ).
   7. Connect the negative (-) terminal cable to the battery.
   8. Turn the ignition switch ON.
   9. Using the intelligent tester, load the previous ECU data stored into the new ECU (see REGISTRATION  ).
   10. Turn the ignition switch OFF.
   11. Turn the ignition switch ON.
   12. Clear the DTCs stored in the memory (see DTC CHECK / CLEAR  ).

       HINT:

       If the DTCs are not cleared at this time, past DTCs will remain.

7. CHECK FOR DTC 
   1. Turn the ignition switch ON.
   2. Clear the DTCs stored in the occupant classification ECU (see DTC CHECK / CLEAR  ).
   3. Clear the DTCs stored in the center airbag sensor (see DTC CHECK / CLEAR  ).
   4. Turn the ignition switch OFF.
   5. Turn the ignition switch ON.
   6. Using the intelligent tester, check for the DTCs of the occupant classification ECU (see DTC CHECK / CLEAR  ).

      OK: 

      DTC B1790 is not output. 

      HINT:

      Codes other than DTC B1790 may be output at this time, but they are not related to this check.

   OK: Go to step  9

   NG: Go to next step 

8. REPLACE CENTER AIRBAG SENSOR ASSEMBLY 
   1. Turn the ignition switch OFF.
   2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
   3. Replace the center airbag sensor (see ON-VEHICLE INSPECTION  ).
9. PERFORM SENSITIVITY CHECK 
   1. Perform the sensitivity check (see INITIALIZATION  ).

   NEXT: END 

10. CHECK FLOOR WIRE 
    1. Turn the ignition switch OFF.
    2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    3. Disconnect the front seat wire RH connector from the floor wire.
    4. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    5. Turn the ignition switch ON.
    6. Measure the voltage according to the value(s) in the table below.

       Standard voltage 

       TESTER CONNECTION SPECIFIED CONDITION
       
       

       Tester Connection	Switch Condition	Specified Condition
       BE2-6 (FSR+) - Body ground	Ignition switch ON	Below 1 V
       BE2-7 (FSR-) - Body ground

       Fig 2: Checking Floor Wire

       Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Measure the resistance according to the value(s) in the table below.

       Standard resistance 

       TESTER CONNECTION SPECIFIED CONDITION
       
       

       Tester Connection	Condition	Specified Condition
       BE2-6 (FSR+) - BE2-7 (FSR-)	Always	Below 1 Ω

    8. Disconnect the service wire from connector B.
    9. Measure the resistance according to the value(s) in the table below.

       Standard resistance 

       TESTER CONNECTION SPECIFIED CONDITION
       
       

       Tester Connection	Condition	Specified Condition
       BE2-6 (FSR+) - BE2-7 (FSR-)	Always	1 MΩ or higher
       BE2-6 (FSR+) - Body ground
       BE2-7 (FSR-) - Body ground

    NG: REPAIR OR REPLACE FLOOR WIRE 

    OK: REPAIR OR REPLACE FRONT SEAT WIRE RH