DTC B1825: Short in Side Squib (LH) Circuit; DTC B1826: Open in Side Squib (LH) Circuit; DTC B1827: Short in Side Squib (LH) Circuit (to Ground); DTC B1828: Short in Side Squib (LH) Circuit (to +B) [05/2019 - ]: Procedure

CHECK FRONT SEAT AIRBAG ASSEMBLY LH

Turn the power switch off.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds.
Disconnect the connector from the front seat airbag assembly LH.
Connect the red wire side of SST (resistance: 2.1 Ω) to connector C.
WARNING:
Never connect the tester to the front seat airbag 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
Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
Turn the power switch on (IG), and wait for at least 60 seconds.
Clear the DTCs.
Refer to DTC CHECK / CLEAR [05/2019 - ]

Body Electrical > SRS Airbag > Clear DTCs
Turn the power switch off.
Turn the power switch on (IG), and wait for at least 60 seconds.

Check for DTCs.

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

Body Electrical > SRS Airbag > Trouble Codes

Result

Proceed to
DTC B1825, B1826, B1827 or B1828 is not output.
DTC B1825, B1826, B1827 or B1828 is output.

HINT:

Codes other than DTC B1825, B1826, B1827 and B1828 may be output at this time, but they are not related to this check.

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

Result:

DTC B1825, B1826, B1827 or B1828 is not output.

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

Result:

DTC B1825, B1826, B1827 or B1828 is output.

See step 2

CHECK CONNECTORS

Disconnect the connectors from the airbag ECU assembly.

Check that the connectors (on the airbag ECU assembly side and front seat airbag assembly LH side) are not damaged.

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 Airbag Assembly LH
*2	No. 2 Floor Wire
*3	Airbag ECU Assembly

Result

Proceed to
OK
NG

Result:

REPLACE NO. 2 FLOOR WIRE

Result:

See step 3

CHECK NO. 2 FLOOR WIRE

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

Turn the power switch on (IG).

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

Standard Voltage

Tester Connection	Switch Condition	Specified Condition
Qd1-1 (SFL+) - Body ground	Power switch on (IG)	Below 1 V
Qd1-2 (SFL-) - Body ground	Power switch on (IG)	Below 1 V

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

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

Standard Resistance

Tester Connection	Condition	Specified Condition
Qd1-1 (SFL+) - Qd1-2 (SFL-)	Always	Below 1 Ω

Release the activation prevention mechanism built into connector B.
Refer to DIAGNOSIS SYSTEM [10/2014 - ]

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

Standard Resistance

Tester Connection	Condition	Specified Condition
Qd1-1 (SFL+) - Qd1-2 (SFL-)	Always	1 MΩ or higher

Restore the released activation prevention mechanism of connector B to its original condition.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
Qd1-1 (SFL+) - Body ground	Always	1 MΩ or higher
Qd1-2 (SFL-) - Body ground	Always	1 MΩ or higher

Result

Proceed to
OK
NG

Result:

REPLACE NO. 2 FLOOR WIRE

Result:

See step 4

CHECK DTC

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

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

Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
Turn the power switch on (IG), and wait for at least 60 seconds.
Clear the DTCs.
Refer to DTC CHECK / CLEAR [05/2019 - ]

Body Electrical > SRS Airbag > Clear DTCs
Turn the power switch off.
Turn the power switch on (IG), and wait for at least 60 seconds.

Check for DTCs.

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

Body Electrical > SRS Airbag > Trouble Codes

Result

Proceed to
DTC B1825, B1826, B1827 or B1828 is not output
DTC B1825, B1826, B1827 or B1828 is output

HINT:

Codes other than DTC B1825, B1826, B1827 and B1828 may be output at this time, but they are not related to this check.

Result:

DTC B1825, B1826, B1827 or B1828 is not output

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

Result:

DTC B1825, B1826, B1827 or B1828 is output

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