Inspection Procedure

HINT:

If troubleshooting (wire harness inspection) is difficult to perform, remove the front passenger seat installation bolts to access the underside 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 ignition switch off.
2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
3. Check that the connectors are properly connected to the occupant classification ECU and the center airbag sensor assembly.
  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 center airbag sensor assembly and the occupant classification ECU.
5. Check that the terminals of the connectors are not damaged.
  OK:
  
  The terminals are not deformed or damaged .
  
  NG: REPLACE WIRE HARNESS
  
  OK: Go to Next Step

CHECK OCCUPANT CLASSIFICATION SYSTEM CIRCUIT (SHORT TO B+)

Connect the cable to the negative (-) battery terminal.
Turn the ignition switch to ON.
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
S2-11 (FSR+) - Body ground	Ignition switch ON	Below 1 V
S2-12 (FSR-) - Body ground	Ignition switch ON	Below 1 V

Fig 1: Checking Occupant Classification System Circuit (Short To B+)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 13

OK: Go to Next Step

CHECK OCCUPANT CLASSIFICATION SYSTEM CIRCUIT (OPEN)

Turn the ignition switch off.
Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
Using SST, connect terminals 12 (FSR+) and 13 (FSR-) of connector B.
NOTE: Do not forcibly insert SST into the terminals of the connector.

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
S2-11 (FSR+) - S2-12 (FSR-)	Always	Below 1 Ω

Fig 2: Checking Occupant Classification System Circuit (Open)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 14

OK: Go to Next Step

CHECK OCCUPANT CLASSIFICATION SYSTEM CIRCUIT (SHORT)

Disconnect SST from connector B.
Measure the resistance according to the value (s) in the table below.

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
S2-11 (FSR+) - S2-12 (FSR-)	Always	1 MΩ or higher

Fig 3: Checking Occupant Classification System Circuit (Short)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 15

OK: Go to Next Step

CHECK OCCUPANT CLASSIFICATION SYSTEM CIRCUIT (SHORT TO GROUND)

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

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
S2-11 (FSR+) - Body ground	Always	1 MΩ or higher
S2-12 (FSR-) - Body ground	Always	1 MΩ or higher

Fig 4: Checking Occupant Classification System Circuit (Short To Ground)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 16

OK: Go to Next Step

RECHECK FOR DTC
1. Connect the connectors to the occupant classification ECU and the center airbag sensor assembly.
2. Connect the Techstream to the DLC3.
3. Connect the cable to the negative (-) battery terminal.
4. Turn the ignition switch to 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 assembly (See DTC CHECK / CLEAR ).
7. Turn the ignition switch off.
8. Turn the ignition switch to ON.
9. Using the Techstream, check for occupant classification ECU 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.
  
  NG: Go to Next Step
  
  OK: USE SIMULATION METHOD TO CHECK (See DIAGNOSIS SYSTEM )
REPLACE FRONT SEAT CUSHION ASSEMBLY
1. Turn the ignition switch off.
2. Disconnect the cable from the negative (-) battery terminal.
3. Replace the front seat cushion assembly (with occupant classification ECU and occupant classification sensor) (See REMOVAL ).
4. Connect the cable to the negative (-) battery terminal.
5. Turn the ignition switch to ON.
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 ignition switch off.
9. Turn the ignition switch to ON.
10. Check for DTCs (See DTC CHECK / CLEAR ).
  OK:
  
  DTC is not output .
RECHECK FOR DTC
1. Turn the ignition switch to 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 assembly (See DTC CHECK / CLEAR ).
4. Turn the ignition switch off.
5. Turn the ignition switch to ON.
6. Using the Techstream, check for occupant classification ECU 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.
  
  NG: Go to step 11
  
  OK: Go to Next Step
PERFORM ZERO POINT CALIBRATION
1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Using the Techstream, perform zero point calibration (See INITIALIZATION ).
4. Turn the ignition switch off.
5. Turn the ignition switch to ON.
6. Clear the DTCs stored in the occupant classification ECU (See DTC CHECK / CLEAR ).
  HINT:
  
  If the DTCs are not cleared at this time, past DTCs will remain.
PERFORM SENSITIVITY CHECK
1. Perform the sensitivity check (See INITIALIZATION ).
  NEXT: END
REPLACE CENTER AIRBAG SENSOR ASSEMBLY
1. Turn the ignition switch off.
2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
3. Replace the center airbag sensor assembly (See CENTER AIRBAG SENSOR ASSEMBLY ).
PERFORM SENSITIVITY CHECK
1. Perform the sensitivity check (See INITIALIZATION ).
  NEXT: END

CHECK NO. 2 FLOOR WIRE (SHORT TO B+)

Turn the ignition switch off.
Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
Disconnect the front seat wire RH connector from the No. 2 floor wire.
Connect the cable to the negative (-) battery terminal.
Turn the ignition switch to ON.
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
MS1-5 (FSR+) - Body ground	Ignition switch ON	Below 1 V
MS1-10 (FSR-) - Body ground	Ignition switch ON	Below 1 V

Fig 5: Checking No. 2 Floor Wire (Short To B+)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE NO. 2 FLOOR WIRE

OK: REPLACE FRONT SEAT WIRE RH

CHECK NO. 2 FLOOR WIRE (OPEN)

Disconnect the front seat wire RH connector from the No. 2 floor wire.

Fig 6: Checking No. 2 Floor Wire (Open)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

SST has already been inserted into connector B.
Measure the resistance according to the value (s) in the table below.

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
MS1-5 (FSR+) - MS1-10 (FSR-)	Always	Below 1 Ω

NG: REPLACE NO. 2 FLOOR WIRE

OK: REPLACE FRONT SEAT WIRE RH

CHECK NO. 2 FLOOR WIRE (SHORT)

Disconnect the front seat wire RH connector from the No. 2 floor wire.
Measure the resistance according to the value (s) in the table below.

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
MS1-5 (FSR+) - MS1-10 (FSR-)	Always	1 MΩ or higher

Fig 7: Checking No. 2 Floor Wire (Short)

NG: REPLACE NO. 2 FLOOR WIRE

OK: REPLACE FRONT SEAT WIRE RH

CHECK NO. 2 FLOOR WIRE (SHORT TO GROUND)

Disconnect the front seat wire RH connector from the No. 2 floor wire.
Measure the resistance according to the value (s) in the table below.

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
MS1-5 (FSR+) - Body ground	Always	1 MΩ or higher
MS1-10 (FSR-) - Body ground	Always	1 MΩ or higher

Fig 8: Checking No. 2 Floor Wire (Short To Ground)

NG: REPLACE NO. 2 FLOOR WIRE

OK: REPLACE FRONT SEAT WIRE RH