Inspection Procedure

HINT:

• If troubleshooting (wire harness inspection) is difficult to perform, remove the front RH seat assy installation bolts to see the under surface of 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 DTC 
   1. Turn the ignition switch to the ON position.
   2. Clear the DTCs stored in memory (see DTC CHECK/CLEAR  ).

      HINT:

      • First clear DTCs stored in the occupant classification ECU and then in the airbag sensor assy center.
      • Use the hand-held tester to clear the DTC of the occupant classification ECU, otherwise the DTC cannot be cleared.
   3. Turn the ignition switch to the LOCK position.
   4. Turn the ignition switch to the ON position.
   5. Using the hand-held tester, check the DTCs of the occupant classification ECU (see DTC CHECK/CLEAR  ).

   OK: 

   DTC B1771 is not output. 

   HINT:

   Codes other than code B1771 may be output at this time, but they are not related to this check.

   NG: Go to step 2 

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

2. CHECK CONNECTION OF CONNECTORS 
   1. Turn the ignition switch to the LOCK position.
   2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
   3. Check that the connectors are properly connected to the occupant classification ECU and the front seat inner belt assy RH.

   OK: 

   The connectors are connected. 

   NG: CONNECT CONNECTORS, THEN GO TO STEP   1 

   OK: Go To Next Step 

3. CHECK FRONT SEAT WIRE RH (TO B+) 
   Fig 1: Checking Front Seat Wire RH (TO B+)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Disconnect the connectors from the occupant classification ECU and the front seat inner belt assy RH.
   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: 

   CONNECTOR TERMINALS VOLTAGE
   
   

   Tester connection	Condition	Specified condition
   04-9 (BSW) - Body ground	Ignition switch ON	Below 1 V
   04-5 (BGND) - Body ground	Ignition switch ON	Below 1 V

   NG: REPAIR OR REPLACE FRONT SEAT WIRE RH 

   OK: Go To Next Step 

4. CHECK FRONT SEAT WIRE RH (OPEN) 
   Fig 2: Checking Front Seat Wire RH (Open)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Turn the ignition switch to the LOCK position.
   2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
   3. Using a service wire, connect B10-1 and B10-2 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: 

      TESTER CONNECTION AND SPECIFIED CONDITION CHART
      
      

      Tester connection	Condition	Specified condition
      04-9 (BSW) - 04-5 (BGND)	Always	Below 1 Ω

      NG: REPAIR OR REPLACE FRONT SEAT WIRE RH 

      OK: Go To Next Step 

   5. CHECK FRONT SEAT WIRE RH (SHORT) 
      Fig 3: Checking Front Seat Wire RH (Short)

      Courtesy 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: 

      CONNECTOR TERMINALS RESISTANCE
      
      

      Tester connection	Condition	Specified condition
      04-9 (BSW) - 04-5 (BGND)	Always	1 MΩ or Higher

      NG: REPAIR OR REPLACE FRONT SEAT WIRE RH 

      OK: Go To Next Step 

   6. CHECK FRONT SEAT WIRE RH (TO GROUND) 
      Fig 4: Checking Front Seat Wire RH (To Ground)

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

         Standard: 

      CONNECTOR TERMINALS RESISTANCE
      
      

      Tester connection	Condition	Specified condition
      04-9 (BSW) - Body ground	Always	1 MΩ or Higher
      04-5 (BGND) - Body ground	Always	1 MΩ or Higher

      NG: REPAIR OR REPLACE FRONT SEAT WIRE RH 

      OK: Go To Next Step 

   7. RECHECK DTC 
      1. Connect the connectors to the occupant classification ECU and the front seat inner belt assy RH.
      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 DTC CHECK/CLEAR  ).

         HINT:

         • First clear DTCs stored in the occupant classification ECU and then in the airbag sensor assy center.
         • Use the hand-held tester to clear the DTC of the occupant classification ECU, otherwise the DTC cannot be cleared.
      5. Turn the ignition switch to the LOCK position.
      6. Turn the ignition switch to the ON position.
      7. Using the hand-held tester, check the DTCs of the occupant classification ECU (see DTC CHECK/CLEAR  ).

      OK: 

      DTC B1771 is not output. 

      HINT:

      Codes other than code B1771 may be output at this time, but they are not related to this check.

      NG: Go to step 8 

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

   8. REPLACE FRONT SEAT INNER BELT ASSY RH 
      1. Turn the ignition switch to the LOCK position.
      2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
      3. Replace the front seat inner belt assy RH (see REPLACEMENT ).

         HINT:

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

      4. Connect the negative (-) terminal cable to the battery.
      5. Turn the ignition switch to the ON position.
      6. Clear the DTCs stored in memory (see DTC CHECK/CLEAR  ).

         HINT:

         • First clear DTCs stored in the occupant classification ECU and then in the airbag sensor assy center.
         • Use the hand-held tester to clear the DTC of the occupant classification ECU, otherwise the DTC cannot be cleared.
      7. Turn the ignition switch to the LOCK position, (h) Turn the ignition switch to the ON position.
      8. Using the hand-held tester, check the DTCs of the occupant classification ECU (see DTC CHECK/CLEAR  ).

      OK: 

      DTC B1771 is not output. 

      HINT:

      Codes other than code B1771 may be output at this time, but they are not related to this check.

      NG: Go to step 9 

      OK 

      END 

   9. REPLACE OCCUPANT CLASSIFICATION ECU 
      1. Turn the ignition switch to the LOCK position.
      2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
      3. Replace the occupant classification ECU (see REPLACEMENT ).

      NEXT: Go To Next Step 

   10. PERFORM ZERO POINT CALIBRATION 
       1. Connect the negative (-) terminal cable to the battery.
       2. Connect the hand-held tester to the DLC3.
       3. Turn the ignition switch to the ON position.
       4. Using the hand-held tester, perform "Zero point calibration" (see INITIALIZATION  ).

       OK: 

       The "COMPLETED" is displayed. 

       NEXT: Go To Next Step 

   11. PERFORM SENSITIVITY CHECK 
       1. Using the hand-held tester, perform "Sensitivity check" (see INITIALIZATION  ).
          1. Standard value: 27 to 33 kg (59.52 to 72.75 lb) 

       NEXT: Go To Next Step 

       END