DTC B1900/73: Short in Front Pretensioner Squib RH Circuit; DTC B1901/73: Open in Front Pretensioner Squib RH Circuit; DTC B1902/73: Short to GND in Front Pretensioner Squib RH Circuit; DTC B1903/73: Short to B+ in Front Pretensioner Squib RH Circuit: Procedure

1. Turn the ignition switch off.
   Fig 1: Identifying Floor Wire & Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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 front seat outer belt assembly RH and 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 front seat outer belt assembly RH and center airbag sensor assembly.
5. Check that the terminals of the connectors are not damaged.

   OK

   The terminals are not deformed or damaged.

6. Check that the floor wire connector (on the front seat outer belt assembly RH side) is not damaged.

   OK

   The lock button is not disengaged, and the claw of the lock is not deformed or damaged.

7. Check that the short spring for the floor wire with the activation prevention mechanism is not deformed or damaged.

   OK

   The short spring is not deformed or damaged.

NG → REPLACE FLOOR WIRE 

OK: Go to next step 

1. Connect the connector to the center airbag sensor assembly.
   Fig 2: Identifying Front Seat Outer Belt Assembly RH (Front Pretensioner Squib RH)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Connect SST (resistance 2.1 Ω) to connector C.
   WARNING:

   Never connect the tester to the front seat outer belt assembly RH (front pretensioner squib RH) for measurement, as this may lead to a serious injury due to airbag deployment.

   NOTE:

   • Do not forcibly insert SST into the terminals of the connector when connecting.
   • Insert SST straight into the terminals of the connector.
   • SST: 09843-18061 
3. Connect the cable to the negative (-) battery terminal.
4. Turn the ignition switch on (IG), and wait for at least 60 seconds.
5. Clear the DTCs stored in the memory, refer to DTC CHECK / CLEAR .
6. Turn the ignition switch off.
7. Turn the ignition switch on (IG), and wait for at least 60 seconds.
8. Check for DTCs, refer to DTC CHECK / CLEAR .

   OK

   DTC B1900, B1901, B1902, B1903 or 73 is not output.

   HINT: 

   Codes other than DTCs B1900, B1901, B1902, B1903 and 73 may be output at this time, but they are not related to this check.

NG → See step   4 

OK → See step   3 

1. Turn the ignition switch off.
   Fig 3: Identifying Floor Wire (Front Pretensioner Squib RH Circuit)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
3. Disconnect SST from connector C.
4. Disconnect the floor wire from the center airbag sensor assembly.
5. Check for a short to B+ in the circuit.
   1. Connect the cable to the negative (-) battery terminal.
   2. Turn the ignition switch on (IG).
   3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection	Switch Condition	Specified Condition
      N4-1 (R+) - Body ground	Ignition switch on (IG)	Below 1 V
      N4-2 (R-) - Body ground	Ignition switch on (IG)	Below 1 V

6. Check for an open in the circuit.
   1. Turn the ignition switch off.
   2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
   3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection	Condition	Specified Condition
      N4-1 (R+) - N4-2 (R-)	Always	Below 1 Ω

7. Check for a short to ground in the circuit.
   1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection	Condition	Specified Condition
      N4-1 (R+) - Body ground	Always	1 MΩ or higher
      N4-2 (R-) - Body ground	Always	1 MΩ or higher

8. Check for a short in the circuit.
   1. Release the activation prevention mechanism built into connector B, refer to DIAGNOSIS SYSTEM .
   2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection	Condition	Specified Condition
      N4-1 (R+) - N4-2 (R-)	Always	1 MΩ or higher

NG → REPLACE FLOOR WIRE 

OK: Go to next step 

1. Restore the released activation prevention mechanism of connector B to the original condition.
   Fig 4: Identifying Center Airbag Sensor Assembly

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Connect the connectors to the front seat outer belt assembly RH and center airbag sensor assembly.
3. Connect the cable to the negative (-) battery terminal.
4. Turn the ignition switch on (IG), and wait for at least 60 seconds.
5. Clear the DTCs stored in the memory, refer to DTC CHECK / CLEAR .
6. Turn the ignition switch off.
7. Turn the ignition switch on (IG), and wait for at least 60 seconds.
8. Check for DTCs, refer to DTC CHECK / CLEAR .

   OK

   DTC B1900, B1901, B1902, B1903 or 73 is not output.

   HINT: 

   Codes other than DTCs B1900, B1901, B1902, B1903 and 73 may be output at this time, but they are not related to this check.

NG → See step   6 

OK → See step   7