CHECK LOWER NO. 1 INSTRUMENT PANEL AIRBAG ASSEMBLY (DRIVER SIDE KNEE AIRBAG SQUIB)
CHECK INSTRUMENT PANEL WIRE (DRIVER SIDE KNEE AIRBAG SQUIB CIRCUIT)
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 |
DESCRIPTION
The driver side knee airbag squib circuit consists of the airbag sensor assembly and lower No. 1 instrument panel airbag assembly.The airbag sensor assembly uses this circuit to deploy the airbag when deployment conditions are met.
These DTCs are stored when a malfunction is detected in the driver side knee airbag squib circuit.
DTC No. | DTC Detection Condition | Trouble Area |
B1860/64 |
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B1861/64 |
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B1862/64 |
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B1863/64 |
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WIRING DIAGRAM

INSPECTION PROCEDURE
- HINT:
- Perform the simulation method by selecting check mode (Signal Check) using the Techstream (YARIS_NCP93 RM000000XFF0B9X.html).
- After selecting check mode (Signal Check), perform the simulation method by wiggling each connector of the airbag system or driving the vehicle on a city or rough road (YARIS_NCP93 RM00000135202EX.html).
1.CHECK CONNECTORS |
Turn the ignition switch off.
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Disconnect the cable from the negative (-) battery terminal.
- CAUTION:
- Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
Check that the connectors are properly connected to the lower No. 1 instrument panel airbag assembly and 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.
Disconnect the connectors from the lower No. 1 instrument panel airbag assembly and airbag sensor assembly.
Check that the terminals of the connectors are not damaged.
- OK:
- The terminals are not deformed or damaged.
Check that the instrument panel wire connector (on the lower No. 1 instrument panel airbag assembly side) is not damaged.
- OK:
- The lock button is not disengaged, and the claw of the lock is not deformed or damaged.
Check that the short spring for the instrument panel wire with the activation prevention mechanism are not deformed or damaged.
- OK:
- The short spring is not deformed or damaged.
Text in Illustration *1 Lower No. 1 Instrument Panel Airbag Assembly *2 Airbag Sensor Assembly *3 Instrument Panel Wire
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OK | |
2.CHECK LOWER NO. 1 INSTRUMENT PANEL AIRBAG ASSEMBLY (DRIVER SIDE KNEE AIRBAG SQUIB) |
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Connect the connector to the airbag sensor assembly.
Connect SST (resistance 2.1 Ω) to connector C.
- CAUTION:
- Never connect the tester to the lower No. 1 instrument panel airbag assembly (driver side knee airbag squib) for measurement, as this may lead to a serious injury due to airbag deployment.
- NOTICE:
- 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
Connect the cable to the negative (-) battery terminal.
Turn the ignition switch to ON, and wait for at least 60 seconds.
Clear the DTCs stored in memory (YARIS_NCP93 RM000000XFE0F4X.html).
Turn the ignition switch off.
Turn the ignition switch to ON, and wait for at least 60 seconds.
Check for DTCs (YARIS_NCP93 RM000000XFE0F4X.html).
- OK:
- DTC B1860/64, B1861/64, B1862/64 or B1863/64 is not output.
Text in Illustration *1 Lower No. 1 Instrument Panel Airbag Assembly *2 Airbag Sensor Assembly *3 Connector C *a Front view of wire harness connector
(to Lower No. 1 Instrument Panel Airbag Assembly)- HINT:
- Codes other than DTCs 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 ignition switch off.
Disconnect the cable from the negative (-) battery terminal.
- CAUTION:
- Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
Disconnect SST from connector C.
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OK | ||
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3.CHECK INSTRUMENT PANEL WIRE (DRIVER SIDE KNEE AIRBAG SQUIB CIRCUIT) |
Disconnect the instrument panel wire from the airbag sensor assembly.
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Check for a short to B+ in the circuit.
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 Switch Condition Specified Condition D114-1 (DK+) - Body ground Ignition switch ON Below 1 V D114-2 (DK-) - Body ground Ignition switch ON Below 1 V
Check for an open in the circuit.
Turn the ignition switch off.
Disconnect the cable from the negative (-) battery terminal.
- CAUTION:
- Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition D114-1 (DK+) - D114-2 (DK-) Always Below 1 Ω
Check for a short to ground in the circuit.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition D114-1 (DK+) - Body ground Always 1 MΩ or higher D114-2 (DK-) - Body ground Always 1 MΩ or higher
Check for a short in the circuit.
Release the activation prevention mechanism built into connector B (YARIS_NCP93 RM000000XFD0EYX.html).
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition D114-1 (DK+) - D114-2 (DK-) Always 1 MΩ or higher
Text in Illustration *1 Lower No. 1 Instrument Panel Airbag Assembly *2 Airbag Sensor Assembly *3 Instrument Panel Wire *4 Connector C *a Front view of wire harness connector
(to Lower No. 1 Instrument Panel Airbag Assembly)
Restore the released activation prevention mechanism of connector B to the original condition.
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OK | |
4.CHECK DTC |
Connect the connectors to the lower No. 1 instrument panel airbag assembly and airbag sensor assembly.
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Connect the cable to the negative (-) battery terminal.
Turn the ignition switch to ON, and wait for at least 60 seconds.
Clear the DTCs stored in memory (YARIS_NCP93 RM000000XFE0F4X.html).
Turn the ignition switch off.
Turn the ignition switch to ON, and wait for at least 60 seconds.
Check for DTCs (YARIS_NCP93 RM000000XFE0F4X.html).
- OK:
- DTC B1860/64, B1861/64, B1862/64 or B1863/64 is not output.
Text in Illustration *1 Lower No. 1 Instrument Panel Airbag Assembly *2 Airbag Sensor Assembly - HINT:
- Codes other than DTCs B1860/64, B1861/64, B1862/64 and B1863/64 may be output at this time, but they are not related to this check.
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OK | ||
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