Inspection Procedure

HINT:

• If troubleshooting (wire harness inspection) is difficult to perform, remove the front seat RH 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 problems, such as seat rail deformation. Hold the seat up only for as long as necessary.

1. CHECK FOR DTC 
   1. Turn the ignition switch ON, and wait for at least 60 seconds.
   2. Clear any DTCs stored in the memory (See DTC CHECK / CLEAR  ).

      HINT:

      • First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor.
      • Use a Techstream to clear the DTCs of the occupant classification ECU, otherwise the DTCs cannot be cleared.
   3. Turn the ignition switch off.
   4. Turn the ignition switch ON, and wait for at least 60 seconds.
   5. Using the Techstream, check for DTCs of the occupant classification ECU (See DTC CHECK / CLEAR  ).

      OK: 

      DTC B1781 is not output. 

      HINT:

      DTCs other than DTC B1781 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 CONNECTOR 
   1. Turn the ignition switch off.
   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 occupant classification sensor RH.

      OK: 

      Connectors are properly connected. 

   NG: CONNECT CONNECTOR 

   OK: Go to next step 

3. CHECK CONNECTOR 
   1. Check that the connectors (on the occupant classification ECU side and front occupant classification sensor RH side) are not damaged (See ELECTRONIC CIRCUIT INSPECTION PROCEDURE ).

      OK: 

      Connectors are not deformed or damaged. 

   NG: REPLACE FRONT SEAT WIRE RH 

   OK: Go to next step 

4. CHECK FRONT SEAT WIRE RH 
   1. Disconnect the connectors from the occupant classification ECU and the front occupant classification sensor RH.
   2. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
   3. Turn the ignition switch ON, and wait for at least 60 seconds.
   4. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART
      
      

      Tester Connection	Switch Condition	Specified Condition
      z8-2 (SGD2) - Body ground	Ignition switch ON	Below 1 V
      z8-8 (SIG2) - Body ground
      z8-12 (SVC2) - Body ground

      Fig 1: Identifying Z8 And Z11 Connector Terminal

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   5. Turn the ignition switch off.
   6. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
   7. Using service wires, connect terminals 1 (SVC2) and 3 (SGD2), and connect terminals 2 (SIG2) and 3 (SGD2) of connector C.
      NOTE: Do not forcibly insert the service wires into the terminals of the connector.
   8. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART
      
      

      Tester Connection	Condition	Specified Condition
      z8-8 (SIG2) - z8-2 (SGD2)	Always	Below 1 Ω
      z8-12 (SVC2) - z8-2 (SGD2)

   9. Disconnect the service wires from connector C.
   10. Measure the resistance according to the value(s) in the table below.

       Standard resistance 

       TESTER CONNECTION SPECIFIED CONDITION CHART
       
       

       Tester Connection	Condition	Specified Condition
       z8-8 (SIG2) - z8-2 (SGD2)	Always	1 MΩ or higher
       z8-12 (SVC2) - z8-2 (SGD2)
       z8-8 (SIG2) - z8-12 (SVC2)
       z8-2 (SGD2) - Body ground
       z8-8 (SIG2) - Body ground
       z8-12 (SVC2) - Body ground

   NG: REPLACE FRONT SEAT WIRE RH 

   OK: Go to next step 

5. CHECK FOR DTC 
   1. Connect the connectors to the occupant classification ECU and the front occupant classification sensor RH.
   2. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
   3. Turn the ignition switch ON, and wait for at least 60 seconds.
   4. Clear any DTCs stored in the memory (See DTC CHECK / CLEAR  ).

      HINT:

      • First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor.
      • Use a Techstream to clear the DTCs of the occupant classification ECU, otherwise the DTCs cannot be cleared.
   5. Turn the ignition switch off.
   6. Turn the ignition switch ON, and wait for at least 60 seconds.
   7. Using the Techstream, check for DTCs of the occupant classification ECU (See DTC CHECK / CLEAR  ).

      OK: 

      DTC B1781 is not output. 

      HINT:

      DTCs other than DTC B1781 may be output at this time, but they are not related to this check.

   NG: Go to step 6 

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

6. REPLACE OCCUPANT CLASSIFICATION ECU 
   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 occupant classification ECU (See REMOVAL  ).

      HINT:

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

7. PERFORM ZERO POINT CALIBRATION 
   1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
   2. Connect a Techstream to the DLC3.
   3. Turn the ignition switch ON, and wait for at least 60 seconds.
   4. Using the Techstream, perform the zero point calibration (See INITIALIZATION  ).

   NG:  Go to step  10

   OK: Go to next step 

8. PERFORM SENSITIVITY CHECK 
   1. Using a Techstream, perform the sensitivity check (See INITIALIZATION  ).

      Standard range: 

      27 to 33 kg (59.5 to 72.8 lb) 

   NG:  Go to step  10

   OK: Go to next step 

9. CHECK FOR DTC 
   1. Turn the ignition switch ON, and wait for at least 60 seconds.
   2. Clear any DTCs stored in the memory (See DTC CHECK / CLEAR  ).

      HINT:

      • First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor.
      • Use a Techstream to clear the DTCs of the occupant classification ECU, otherwise the DTCs cannot be cleared.
   3. Turn the ignition switch off.
   4. Turn the ignition switch ON, and wait for at least 60 seconds.
   5. Using the Techstream, check for DTCs of the occupant classification ECU (See DTC CHECK / CLEAR  ).

      OK: 

      DTC B1781 is not output. 

      HINT:

      DTCs other than DTC B1781 may be output at this time, but they are not related to this check.

   NG: Go to step 10 

   OK : END 

10. REPLACE FRONT SEAT FRAME WITH ADJUSTER ASSEMBLY RH 
    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 front seat frame with adjuster RH (See DISASSEMBLY ).

       HINT:

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

11. PERFORM ZERO POINT CALIBRATION 
    1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    2. Connect a Techstream to the DLC3.
    3. Turn the ignition switch ON, and wait for at least 60 seconds.
    4. Using the Techstream, perform the zero point calibration (See INITIALIZATION  ).
12. PERFORM SENSITIVITY CHECK 
    1. Using a Techstream, perform the sensitivity check (See INITIALIZATION  ).

       Standard range: 

       27 to 33 kg (59.5 to 72.8 lb) 

    NEXT : END