DTC B1905: Short in P/T Squib (LH) Circuit; DTC B1906: Open in P/T Squib (LH) Circuit; DTC B1907: Short in P/T Squib (LH) Circuit (to Ground); DTC B1908: Short in P/T Squib (LH) Circuit (to +B) [05/2019 - ]: Procedure

1. Turn the power switch off.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	Front Seat Outer Belt Assembly LH
   *2	Airbag ECU Assembly
   *3	Connector C
   *4	SST
   *a	Front view of wire harness connector (to Front Seat Outer Belt Assembly LH)

2. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds.
3. Disconnect the connector from the front seat outer belt assembly LH.
4. Connect the white wire side of SST (resistance: 2.1 Ω) to connector C.
   WARNING:

   Never connect the tester to the front seat outer belt assembly LH 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 SST.
   • Insert SST straight into the terminals of the connector.
   • SST: 09843-18061 
5. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
6. Turn the power switch on (IG), and wait for at least 60 seconds.
7. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [05/2019 - ]

   Body Electrical > SRS Airbag > Clear DTCs 

8. Turn the power switch off.
9. Turn the power switch on (IG), and wait for at least 60 seconds.
10. Check for DTCs.

    Refer to DTC CHECK / CLEAR [05/2019 - ]

    Body Electrical > SRS Airbag > Trouble Codes 

    Result

    Proceed to
    DTC B1905, B1906, B1907 or B1908 is not output
    DTC B1905, B1906, B1907 or B1908 is output

    HINT: 

    Codes other than DTC B1905, B1906, B1907 and B1908 may be output at this time, but they are not related to this check.

11. Turn the power switch off.
12. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds.
13. Disconnect SST from connector C.

Result: 

DTC B1905, B1906, B1907 or B1908 is not output 

REPLACE FRONT SEAT OUTER BELT ASSEMBLY LH. Refer to  REMOVAL [05/2019 - ] 

Result: 

DTC B1905, B1906, B1907 or B1908 is output 

See step  2

1. Disconnect the connectors from the airbag ECU assembly.
2. Check that the connectors (on the airbag ECU assembly side and front seat outer belt assembly LH side) are not damaged.

   OK

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	Front Seat Outer Belt Assembly LH
   *2	No. 2 Floor Wire
   *3	Airbag ECU Assembly

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE NO. 2 FLOOR WIRE 

Result: 

OK 

See step  3

1. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	Front Seat Outer Belt Assembly LH
   *2	No. 2 Floor Wire
   *3	Airbag ECU Assembly
   *4	Connector C
   *a	Front view of wire harness connector (to Front Seat Outer Belt Assembly LH)

2. Turn the power switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   Q4-1 (L-) - Body ground	Power switch on (IG)	Below 1 V
   Q4-2 (L+) - Body ground	Power switch on (IG)	Below 1 V

4. Turn the power switch off.
5. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds.
6. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   Q4-1 (L-) - Q4-2 (L+)	Always	Below 1 Ω

7. Release the activation prevention mechanism built into connector B.

   Refer to DIAGNOSIS SYSTEM [10/2014 - ]

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   Q4-1 (L-) - Q4-2 (L+)	Always	1 MΩ or higher

9. Restore the released activation prevention mechanism of connector B to its original condition.
10. Measure the resistance according to the value(s) in the table below.

    Standard Resistance

    Tester Connection	Condition	Specified Condition
    Q4-1 (L-) - Body ground	Always	1 MΩ or higher
    Q4-2 (L+) - Body ground	Always	1 MΩ or higher

    Result

    Proceed to
    OK
    NG

Result: 

NG 

REPLACE NO. 2 FLOOR WIRE 

Result: 

OK 

See step  4

1. Connect the connectors to the front seat outer belt assembly LH and airbag ECU assembly.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	Front Seat Outer Belt Assembly LH
   *2	Airbag ECU Assembly

2. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
3. Turn the power switch on (IG), and wait for at least 60 seconds.
4. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [05/2019 - ]

   Body Electrical > SRS Airbag > Clear DTCs 

5. Turn the power switch off.
6. Turn the power switch on (IG), and wait for at least 60 seconds.
7. Check for DTCs.

   Refer to DTC CHECK / CLEAR [05/2019 - ]

   Body Electrical > SRS Airbag > Trouble Codes 

   Result

   Proceed to
   DTC B1905, B1906, B1907 or B1908 is not output
   DTC B1905, B1906, B1907 or B1908 is output

   HINT: 

   Codes other than DTC B1905, B1906, B1907 and B1908 may be output at this time, but they are not related to this check.

Result: 

DTC B1905, B1906, B1907 or B1908 is not output 

USE SIMULATION METHOD TO CHECK. Refer to  DIAGNOSIS SYSTEM [10/2014 - ] 

Result: 

DTC B1905, B1906, B1907 or B1908 is output 

REPLACE AIRBAG ECU ASSEMBLY. Refer to  REMOVAL [05/2019 - ]