Supplemental Restraint Systems. Dtc B1815/54 Short In Front Passenger Side Squib 2Nd Step Circuit

Vehicle Interior. Yaris. Ncp93, 131

Supplemental Restraint Systems. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK FRONT PASSENGER AIRBAG (FRONT PASSENGER SIDE SQUIB 2ND STEP)

CHECK CONNECTOR

CHECK FRONT PASSENGER SIDE SQUIB 2ND STEP CIRCUIT

CHECK CENTER AIRBAG SENSOR ASSEMBLY

CHECK INSTRUMENT PANEL WIRE

CHECK INSTRUMENT PANEL WIRE ASSEMBLY

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 center airbag sensor assembly and the front passenger airbag assembly.
The circuit signals the SRS to deploy when deployment conditions are met.
These DTCs are recorded when a malfunction is detected in the front passenger side squib 2nd step circuit.

DTC No.	DTC Detecting Condition	Trouble Area
B1815/54	Center airbag sensor assembly detects line short circuit signal in front passenger side squib 2nd step circuit 5 times during primary check. Front passenger side squib 2nd step malfunction Center airbag sensor assembly malfunction	Instrument panel wire Instrument panel wire assembly Front passenger airbag assembly (Front passenger side squib 2nd step) Center airbag sensor assembly
B1816/54	Center airbag sensor assembly detects open circuit signal in front passenger side squib 2nd step circuit for 2 seconds. Front passenger side squib 2nd step malfunction Center airbag sensor assembly malfunction	Instrument panel wire Instrument panel wire assembly Front passenger airbag assembly (Front passenger side squib 2nd step) Center airbag sensor assembly
B1817/54	Center airbag sensor assembly detects short circuit to ground signal in front passenger side squib 2nd step circuit for 0.5 seconds. Front passenger side squib 2nd step malfunction Center airbag sensor assembly malfunction	Instrument panel wire Instrument panel wire assembly Front passenger airbag assembly (Front passenger side squib 2nd step) Center airbag sensor assembly
B1818/54	Center airbag sensor assembly detects short circuit to B+ signal in front passenger side squib 2nd step circuit for 0.5 seconds. Front passenger side squib 2nd step malfunction Center airbag sensor assembly malfunction	Instrument panel wire Instrument panel wire assembly Front passenger airbag assembly (Front passenger side squib 2nd step) Center airbag sensor assembly

WIRING DIAGRAM

Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan).
Dtc
B1815/54 Short In Front Passenger Side Squib 2Nd Step Circuit

INSPECTION PROCEDURE

HINT:

Perform the simulation method by selecting CHECK MODE (signal check) with the Techstream (YARIS_NCP93 RM000000XFF09MX.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 RM000000XFD0CVX.html).

1.CHECK FRONT PASSENGER AIRBAG (FRONT PASSENGER SIDE SQUIB 2ND STEP)

SST: 09843-18060

Turn the ignition switch off.

Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

Disconnect the connectors from the front passenger airbag assembly.

Connect the white wire side of SST (resistance 2.1 Ω) to connector E (black connector).
CAUTION:
Never connect a tester to the front passenger airbag assembly (front passenger side squib 2nd step) for measurement, as this may lead to a serious injury due to airbag deployment.
NOTICE:
1. Do not forcibly insert the SST into the terminals of the connector when connecting.
2. Insert the SST straight into the terminals of the connector.

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

Turn the ignition switch on, and wait for at least 60 seconds.

Clear the DTCs stored in the memory (YARIS_NCP93 RM000000XFE0D2X.html).

Turn the ignition switch off.

Turn the ignition switch on, and wait for at least 60 seconds.

Check the DTCs (YARIS_NCP93 RM000000XFE0D2X.html).
OK:
DTC B1815, B1816, B1817, B1818 and 54 are not output.
HINT:
DTCs other than DTC B1815, B1816, B1817, B1818 and 54 may be output at this time, but they are not related to this check.

REPLACE FRONT PASSENGER AIRBAG

NG

2.CHECK CONNECTOR

Turn the ignition switch off.

Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

Disconnect the SST from connector E.

Check that the instrument panel wire assembly connectors (on the front passenger airbag side) are not damaged.
OK:
The lock button is not disengaged, and the claw of the lock is not damaged or deformed.

REPAIR OR REPLACE INSTRUMENT PANEL WIRE ASSEMBLY

OK

3.CHECK FRONT PASSENGER SIDE SQUIB 2ND STEP CIRCUIT

Disconnect the connectors from the center airbag sensor assembly.

Check for short to B+ in the circuit.
1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
2. Turn the ignition switch on.
3. Measure the voltage.
  Standard voltage:
  Tester Connection
  Switch Condition
  Specified Condition
  Q2-2 (P2+) - Body ground
  Ignition switch ON
  Below 1 V
  Q2-1 (P2-) - Body ground
  Ignition switch ON
  Below 1 V

Check for open in the circuit.
1. Turn the ignition switch off.
2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
3. Measure the resistance.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  Q2-2 (P2+) - Q2-1 (P2-)
  Always
  Below 1 Ω

Check for short to ground in the circuit.
1. Measure the resistance.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  Q2-2 (P2+) - Body ground
  Always
  1 MΩ or higher
  Q2-1 (P2-) - Body ground
  Always
  1 MΩ or higher

Check for short in the circuit.
1. Release the activation prevention mechanism built into connector B (YARIS_NCP93 RM000000XFD0CVX.html).
2. Measure the resistance.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  Q2-2 (P2+) - Q2-1 (P2-)
  Always
  1 MΩ or higher

Go to step 5

OK

4.CHECK CENTER AIRBAG SENSOR ASSEMBLY

Connect the connectors to the front passenger airbag assembly and the center airbag sensor assembly.

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

Turn the ignition switch on, and wait for at least 60 seconds.

Clear the DTCs stored in the memory (YARIS_NCP93 RM000000XFE0D2X.html).

Turn the ignition switch off.

Turn the ignition switch on, and wait for at least 60 seconds.

Check the DTCs (YARIS_NCP93 RM000000XFE0D2X.html).
OK:
DTC B1815, B1816, B1817, B1818 and 54 are not output.
HINT:
DTCs other than DTC B1815, B1816, B1817, B1818 and 54 may be output at this time, but they are not related to this check.

REPLACE CENTER AIRBAG SENSOR ASSEMBLY

USE SIMULATION METHOD TO CHECK

5.CHECK INSTRUMENT PANEL WIRE

Check for short to B+ in the circuit.
1. Restore the released activation prevention mechanism of connector B to the original condition.
2. Disconnect the instrument panel wire connector from the instrument panel wire assembly.
3. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
4. Turn the ignition switch on.
5. Measure the voltage.
  Standard voltage:
  Tester Connection
  Switch Condition
  Specified Condition
  DQ1-3 (P2+) - Body ground
  Ignition switch ON
  Below 1 V
  DQ1-4 (P2-) - Body ground
  Ignition switch ON
  Below 1 V

Check for open in the circuit.
1. Turn the ignition switch off.
2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
3. Measure the resistance.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  DQ1-3 (P2+) - DQ1-4 (P2-)
  Always
  Below 1 Ω

Check for short to ground in the circuit.
1. Measure the resistance.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  DQ1-3 (P2+) - Body ground
  Always
  1 MΩ or higher
  DQ1-4 (P2-) - Body ground
  Always
  1 MΩ or higher

Check for short in the circuit.
1. Release the activation prevention mechanism built into connector B (YARIS_NCP93 RM000000XFD0CVX.html).
2. Measure the resistance.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  DQ1-3 (P2+) - DQ1-4 (P2-)
  Always
  1 MΩ or higher

REPAIR OR REPLACE INSTRUMENT PANEL WIRE

OK

6.CHECK INSTRUMENT PANEL WIRE ASSEMBLY

Check for short to B+ in the circuit.
1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
2. Turn the ignition switch on.
3. Measure the voltage.
  Standard voltage:
  Tester Connection
  Switch Condition
  Specified Condition
  Q2-2 (P2+) - Body ground
  Ignition switch ON
  Below 1 V
  Q2-1 (P2-) - Body ground
  Ignition switch ON
  Below 1 V

Check for open in the circuit.
1. Turn the ignition switch off.
2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
3. Measure the resistance.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  Q2-2 (P2+) - Q2-1 (P2-)
  Always
  Below 1 Ω

Check for short to ground in the circuit.
1. Measure the resistance.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  Q2-2 (P2+) - Body ground
  Always
  1 MΩ or higher
  Q2-1 (P2-) - Body ground
  Always
  1 MΩ or higher

Check for short in the circuit.
1. Release the activation prevention mechanism built into connector D (YARIS_NCP93 RM000000XFD0CVX.html).
2. Measure the resistance.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  Q2-2 (P2+) - Q2-1 (P2-)
  Always
  1 MΩ or higher

REPAIR OR REPLACE INSTRUMENT PANEL WIRE ASSEMBLY

USE SIMULATION METHOD TO CHECK

Tester Connection	Switch Condition	Specified Condition
Q2-2 (P2+) - Body ground	Ignition switch ON	Below 1 V
Q2-1 (P2-) - Body ground	Ignition switch ON	Below 1 V

Tester Connection	Condition	Specified Condition
Q2-2 (P2+) - Q2-1 (P2-)	Always	Below 1 Ω