Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

If troubleshooting (wire harness inspection) is difficult to perform, remove the front passenger seat installation bolts to access 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 damage the seat or deform the seat rails Hold the seat only as necessary

CHECK CONNECTORS
1. Turn the engine switch off.
2. Disconnect the cable from the negative (-) battery terminal
3. Check that the connectors are properly connected to the occupant classification ECU and the front seat inner belt assembly RH.
  OK: The connectors are properly connected.
  
  HINT
  
  If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.
4. Disconnect the connectors from the occupant classification ECU and the front seat inner belt assembly RH.
5. Check that the terminals of the connectors are not damaged.
  OK: The terminals are not deformed or damaged.
NG: REPLACE FRONT SEAT WIRE RH

OK: Go to next step

CHECK FRONT SEAT WIRE RH (SHORT TO B+)

Connect the cable to the negative (-) battery terminal.
Turn the engine switch on (IG).

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
T16-13 (BSW) -Body ground	Engine switch on (IG)	Below 1 V
T16-14 (BGND) - Body ground	Engine switch on (IG)	Below 1 V

Fig 1: Identifying Front Seat Wire RH (Short To B+)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE FRONT SEAT WIRE RH

OK: Go to next step

CHECK FRONT SEAT WIRE RH (OPEN)

Turn the engine switch off.

Fig 2: Identifying Front Seat Wire RH (Open)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Disconnect the cable from the negative (-) battery terminal.
Using SST, connect terminals 1 (RBE-) and 2 (RBE+) of connector C.
NOTE: Do not forcibly insert SST into the terminals of the connector when connecting the wire.

SST 09843-18040

Measure the resistance according to the value(s) in the table below

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester connection	Condition	Specified condition
T16-13 (BSW) - T16-14 (BGND)	Always	Below 1 Ω

NG: REPLACE FRONT SEAT WIRE RH

OK: Go to next step

CHECK FRONT SEAT WIRE RH (SHORT TO GROUND)

Disconnect SST from connector C

Measure the resistance according to the value(s) in the table below

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester connection	Condition	Specified condition
T16-13 (BSW) - Body ground	Always	1 MΩ or higher
T16-14 (BGND) - Body ground	Always	1 MΩ or higher

Fig 3: Identifying Front Seat Wire RH (Short To Ground)

NG: REPLACE FRONT SEAT WIRE RH

OK: Go to next step

CHECK FRONT SEAT WIRE RH (SHORT)

Measure the resistance according to the value(s) in the table below.

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester connection	Condition	Specified condition
T16-13 (BSW) - T16-14 (BGND)	Always	1 MΩ or higher

Fig 4: Identifying Front Seat Wire RH (Short)

NG: REPLACE FRONT SEAT WIRE RH

OK: Go to next step

CHECK DTC
1. Connect the connectors to the occupant classification ECU and the front seat inner belt assembly RH
2. Connect the cable to the negative (-) battery terminal.
3. Turn the engine switch on (IG).
4. Clear the DTCs stored in the occupant classification ECU (See DTC CHECK / CLEAR ).
5. Clear the DTCs stored in the center airbag sensor assembly (See DTC CHECK / CLEAR )
6. Turn the engine switch off
7. Turn the engine switch on (IG).
8. Check for DTCs (See DTC CHECK / CLEAR )
  OK: DTC B1771 is not output.
  
  HINT:
  
  Codes other than B1771 may be output at this time, but they are not related to this check.
NG: Go to step 7

OK: USE SIMULATION METHOD TO CHECK (See DIAGNOSIS SYSTEM )
INSPECT FRONT SEAT INNER BELT ASSEMBLY RH
1. Turn the engine switch off
2. Disconnect the cable from the negative (-) battery terminal
3. Replace the front seat inner belt assembly RH with a known good part (See REMOVAL ).
  HINT
  
  Perform an inspection using known good parts from another vehicle if possible.
4. Connect the cable to the negative (-) battery terminal.
5. Turn the engine switch on (IG)
6. Clear the DTCs stored in the occupant classification ECU (See DTC CHECK / CLEAR )
7. Clear the DTCs stored in the center airbag sensor assembly (See DTC CHECK / CLEAR )
8. Turn the engine switch off.
9. Turn the engine switch on (IG).
10. Check for DTCs (See DTC CHECK / CLEAR )
  OK: DTC B1771 is not output.
  
  HINT:
  
  Codes other than B1771 may be output at this time, but they are not related to this check.
NG: Go to step 8

OK: END
REPLACE OCCUPANT CLASSIFICATION ECU
1. Connect the Techstream to the DLC3
2. Turn the engine switch on (IG)
3. Using the Techstream, save the ECU data from the ECU currently installed on the vehicle (See REGISTRATION ).
4. Turn the engine switch off
5. Disconnect the cable from the negative (-) battery terminal.
6. Replace the occupant classification ECU (See REMOVAL )
7. Connect the cable to the negative (-) battery terminal.
8. Turn the engine switch on (IG)
9. Using the Techstream, load the previous ECU data stored into the new ECU (See REGISTRATION )
10. Turn the engine switch off
11. Turn the engine switch on (IG)
12. Clear the DTCs stored in the memory (See DTC CHECK / CLEAR ).
  HINT
  
  If the DTCs are not cleared at this time, past DTC will remain
PERFORM SENSITIVITY CHECK
1. Perform the sensitivity check (See INITIALIZATION )
NEXT: END