DTC B1860-64: Short in Driver Side Knee Airbag Squib Circuit; DTC B1861-64: Open in Driver Side Knee Airbag Squib Circuit; DTC B1862-64: Short to GND in Driver Side Knee Airbag Squib Circuit; DTC B1863-64: Short to B+ in Driver Side Knee Airbag Squib Circuit [10/2014 - 05/2019]: Procedure

CHECK LOWER NO. 1 INSTRUMENT PANEL AIRBAG ASSEMBLY

Turn the power switch off.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	Lower No. 1 Instrument Panel Airbag Assembly
*2	Airbag ECU Assembly
*3	Connector C
*4	SST
*a	Front view of wire harness connector (to Lower No. 1 Instrument Panel Airbag Assembly)

Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds.
Disconnect the connector from the lower No. 1 instrument panel airbag assembly.
Connect the white wire side of SST (resistance: 2.1 Ω) to connector C.
WARNING:
Never connect the tester to the lower No. 1 instrument panel airbag assembly 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 [10/2014 - 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 [10/2014 - 05/2019]

Body Electrical > SRS Airbag > Trouble Codes

Result

Proceed to
DTC B1860/64, B1861/64, B1862/64 or B1863/64 is not output
DTC B1860/64, B1861/64, B1862/64 or B1863/64 is output

HINT:

Codes other than DTC B1860/64, B1861/64, B1862/64 and B1863/64 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 B1860/64, B1861/64, B1862/64 or B1863/64 is not output

REPLACE LOWER NO. 1 INSTRUMENT PANEL AIRBAG ASSEMBLY. Refer to REMOVAL [10/2014 - 05/2019]

Result:

DTC B1860/64, B1861/64, B1862/64 or B1863/64 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 lower No. 1 instrument panel airbag assembly 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	Lower No. 1 Instrument Panel Airbag Assembly
*2	Instrument Panel Wire
*3	Airbag ECU Assembly

Result

Proceed to
OK
NG

Result:

REPLACE INSTRUMENT PANEL WIRE

Result:

See step 3

CHECK INSTRUMENT PANEL WIRE

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	Lower No. 1 Instrument Panel Airbag Assembly
*2	Instrument Panel Wire
*3	Airbag ECU Assembly
*4	Connector C
*a	Front view of wire harness connector (to Lower No. 1 Instrument Panel Airbag Assembly)

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
I18-1 (DK+) - Body ground	Power switch on (IG)	Below 1 V
I18-2 (DK-) - 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
I18-1 (DK+) - I18-2 (DK-)	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
I18-1 (DK+) - I18-2 (DK-)	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
I18-1 (DK+) - Body ground	Always	1 MΩ or higher
I18-2 (DK-) - Body ground	Always	1 MΩ or higher

Result

Proceed to
OK
NG

Result:

REPLACE INSTRUMENT PANEL WIRE

Result:

See step 4

CHECK DTC

Connect the connectors to the lower No. 1 instrument panel airbag assembly and airbag ECU assembly.

*1	Lower No. 1 Instrument Panel Airbag Assembly
*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 [10/2014 - 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 [10/2014 - 05/2019]

Body Electrical > SRS Airbag > Trouble Codes

Result

Proceed to
DTC B1860/64, B1861/64, B1862/64 or B1863/64 is not output
DTC B1860/64, B1861/64, B1862/64 or B1863/64 is output

HINT:

Codes other than DTC B1860/64, B1861/64, B1862/64 and B1863/64 may be output at this time, but they are not related to this check.

Result:

DTC B1860/64, B1861/64, B1862/64 or B1863/64 is not output

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

Result:

DTC B1860/64, B1861/64, B1862/64 or B1863/64 is output

REPLACE AIRBAG ECU ASSEMBLY. Refer to REMOVAL [10/2014 - 05/2019]