CHECK INSTRUMENT PANEL PASSENGER AIRBAG ASSEMBLY (FRONT PASSENGER SIDE SQUIB 2ND STEP)
CHECK FRONT PASSENGER SIDE SQUIB 2ND STEP CIRCUIT
CHECK NO. 2 INSTRUMENT PANEL WIRE
DTC B1815/54 Short in Front Passenger Side Squib 2nd Step Circuit |
DTC B1816/54 Open in Front Passenger Side Squib 2nd Step Circuit |
DTC B1817/54 Short to GND in Front Passenger Side Squib 2nd Step Circuit |
DTC B1818/54 Short to B+ in Front Passenger Side Squib 2nd Step Circuit |
DESCRIPTION
The front passenger side squib 2nd step circuit consists of the airbag sensor assembly and instrument panel passenger 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 front passenger side squib 2nd step circuit.
DTC No. | DTC Detection Condition | Trouble Area |
B1815/54 |
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B1816/54 |
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B1817/54 |
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B1818/54 |
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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 |
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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.
Check that the connectors are properly connected to the instrument panel passenger airbag assembly and airbag sensor assembly. Also check that the connectors that link the instrument panel wire and No. 2 instrument panel wire are properly connected.
- 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 instrument panel passenger airbag assembly and airbag sensor assembly. Also disconnect the instrument panel wire from the No. 2 instrument panel wire.
Check that the terminals of the connectors are not damaged.
- OK:
- The terminals are not deformed or damaged.
Check that the No. 2 instrument panel wire connector (on the instrument panel passenger airbag assembly side) is not damaged.
- OK:
- The lock button is not disengaged, or the claw of the lock is not deformed or damaged.
Check that the short springs for the instrument panel wire and No. 2 instrument panel wire with the activation prevention mechanism are not deformed or damaged.
- OK:
- The short springs are not deformed or damaged.
Text in Illustration *1 Instrument Panel Passenger Airbag Assembly *2 Airbag Sensor Assembly *3 No. 2 Instrument Panel Wire *4 Instrument Panel Wire
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OK | |
2.CHECK INSTRUMENT PANEL PASSENGER AIRBAG ASSEMBLY (FRONT PASSENGER SIDE SQUIB 2ND STEP) |
Connect the instrument panel wire to the No. 2 instrument panel wire and airbag sensor assembly.
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Connect SST (resistance 2.1 Ω) to connector E (black connector).
- CAUTION:
- Never connect the tester to the instrument panel passenger airbag assembly (front passenger side squib 2nd step) 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 B1815/54, B1816/54, B1817/54 or B1818/54 is not output.
Text in Illustration *1 Instrument Panel Passenger Airbag Assembly *2 Airbag Sensor Assembly *3 Connector E *a Front view of wire harness connector
(to Instrument Panel Passenger Airbag Assembly)*b Color: Black - HINT:
- Codes other than DTCs B1815/54, B1816/54, B1817/54 and B1818/54 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 E.
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OK | ||
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3.CHECK FRONT PASSENGER SIDE SQUIB 2ND STEP 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 Q11-2 (P2+) - Body ground Ignition switch ON Below 1 V Q11-1 (P2-) - 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 Q11-2 (P2+) - Q11-1 (P2-) 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 Q11-2 (P2+) - Body ground Always 1 MΩ or higher Q11-1 (P2-) - 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 Q11-2 (P2+) - Q11-1 (P2-) Always 1 MΩ or higher
Text in Illustration *1 Instrument Panel Passenger Airbag Assembly *2 Airbag Sensor Assembly *3 Connector E *a Front view of wire harness connector
(to Instrument Panel Passenger Airbag Assembly)*b Color: Black
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 instrument panel passenger 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 B1815/54, B1816/54, B1817/54 or B1818/54 is not output.
Text in Illustration *1 Instrument Panel Passenger Airbag Assembly *2 Airbag Sensor Assembly - HINT:
- Codes other than DTCs B1815/54, B1816/54, B1817/54 and B1818/54 may be output at this time, but they are not related to this check.
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OK | ||
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5.CHECK INSTRUMENT PANEL WIRE |
Disconnect the No. 2 instrument panel wire from the instrument panel wire.
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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 DQ3-3 (P2+) - Body ground Ignition switch ON Below 1 V DQ3-4 (P2-) - 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 DQ3-3 (P2+) - DQ3-4 (P2-) 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 DQ3-3 (P2+) - Body ground Always 1 MΩ or higher DQ3-4 (P2-) - 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 DQ3-3 (P2+) - DQ3-4 (P2-) Always 1 MΩ or higher
Text in Illustration *1 Instrument Panel Passenger Airbag Assembly *2 Airbag Sensor Assembly *3 No. 2 Instrument Panel Wire *4 Instrument Panel Wire *5 Connector C *a Front view of wire harness connector
(to No. 2 Instrument Panel Wire)
Restore the released activation prevention mechanism of connector B to the original condition.
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OK | |
6.CHECK NO. 2 INSTRUMENT PANEL WIRE |
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 Q11-2 (P2+) - Body ground Ignition switch ON Below 1 V Q11-1 (P2-) - Body ground Ignition switch ON Below 1 V
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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 Q11-2 (P2+) - Q11-1 (P2-) 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 Q11-2 (P2+) - Body ground Always 1 MΩ or higher Q11-1 (P2-) - Body ground Always 1 MΩ or higher
Check for a short in the circuit.
Release the activation prevention mechanism built into connector D (YARIS_NCP93 RM000000XFD0EYX.html).
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition Q11-2 (P2+) - Q11-1 (P2-) Always 1 MΩ or higher
Text in Illustration *1 Instrument Panel Passenger Airbag Assembly *2 Airbag Sensor Assembly *3 No. 2 Instrument Panel Wire *4 Instrument Panel Wire *5 Connector E *a Front view of wire harness connector
(to Instrument Panel Passenger Airbag Assembly)*b Color: Black
Restore the released activation prevention mechanism of connector D to the original condition.
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OK | ||
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