Dtc B1800/51 Short In Driver Side Squib Circuit

Vehicle Interior. Yaris. Ncp93, 131
Supplemental Restraint Systems. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK STEERING PAD (DRIVER SIDE SQUIB)

CHECK CONNECTOR

CHECK DRIVER SIDE SQUIB CIRCUIT

CHECK CENTER AIRBAG SENSOR ASSEMBLY

CHECK INSTRUMENT PANEL WIRE

CHECK SPIRAL CABLE

DTC B1800/51 Short in Driver Side Squib Circuit

DTC B1801/51 Open in Driver Side Squib Circuit

DTC B1802/51 Short to GND in Driver Side Squib Circuit

DTC B1803/51 Short to B+ in Driver Side Squib Circuit


DESCRIPTION

  1. The driver side squib circuit consists of the center airbag sensor assembly, the spiral cable and the steering pad.
  2. The circuit signals the SRS to deploy when deployment conditions are met.
  3. These DTCs are recorded when a malfunction is detected in the driver side squib circuit.

DTC No.
DTC Detecting Condition
Trouble Area
B1800/51
  1. Center airbag sensor assembly detects line short circuit signal in driver side squib circuit 5 times during primary check.
  2. Driver side squib malfunction
  3. Spiral cable malfunction
  4. Center airbag sensor assembly malfunction
  1. Instrument panel wire
  2. Spiral cable
  3. Steering pad (Driver side squib)
  4. Center airbag sensor assembly
B1801/51
  1. Center airbag sensor assembly detects open circuit signal in driver side squib circuit for 2 seconds.
  2. Driver side squib malfunction
  3. Spiral cable malfunction
  4. Center airbag sensor assembly malfunction
  1. Instrument panel wire
  2. Spiral cable
  3. Steering pad (Driver side squib)
  4. Center airbag sensor assembly
B1802/51
  1. Center airbag sensor assembly detects short circuit to ground signal in driver side squib circuit for 0.5 seconds.
  2. Driver side squib malfunction
  3. Spiral cable malfunction
  4. Center airbag sensor assembly malfunction
  1. Instrument panel wire
  2. Spiral cable
  3. Steering pad (Driver side squib)
  4. Center airbag sensor assembly
B1803/51
  1. Center airbag sensor assembly detects short circuit to B+ signal in driver side squib circuit for 0.5 seconds.
  2. Driver side squib malfunction
  3. Spiral cable malfunction
  4. Center airbag sensor assembly malfunction
  1. Instrument panel wire
  2. Spiral cable
  3. Steering pad (Driver side squib)
  4. Center airbag sensor assembly

WIRING DIAGRAM


Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1800/51 Short In Driver Side Squib Circuit


INSPECTION PROCEDURE

HINT:
  1. Perform the simulation method by selecting CHECK MODE (signal check) with the Techstream (YARIS_NCP93 RM000000XFF09MX.html).
  2. 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 STEERING PAD (DRIVER SIDE SQUIB)
SST
09843-18060


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1800/51 Short In Driver Side Squib Circuit

  1. Turn the ignition switch off.

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

  1. Disconnect the connectors from the steering pad.

  1. Connect the white wire side of SST (resistance 2.1 Ω) to connector E (orange connector).

    CAUTION:
    Never connect a tester to the steering pad (driver side squib) 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.

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

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

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

  1. Turn the ignition switch off.

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

  1. Check the DTCs (YARIS_NCP93 RM000000XFE0D2X.html).

    OK:
    DTC B1800, B1801, B1802, B1803 and 51 are not output.
    HINT:
    DTCs other than DTC B1800, B1801, B1802, B1803 and 51 may be output at this time, but they are not related to this check.


OK
REPLACE STEERING PAD
NG


2.CHECK CONNECTOR

  1. Turn the ignition switch off.

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

  1. Disconnect the SST from connector E.

  1. Check that the spiral cable connectors (on the steering pad side) are not damaged.

    OK:
    The lock button is not disengaged, and the claw of the lock is not deformed or damaged.


NG
REPLACE SPIRAL CABLE
OK


3.CHECK DRIVER SIDE SQUIB CIRCUIT


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1800/51 Short In Driver Side Squib Circuit

  1. Disconnect the connectors from the center airbag sensor assembly and steering pad.

  1. 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
      W1-1 (D+) - Body ground
      		Ignition switch ON
      		Below 1 V
      W1-2 (D-) - Body ground
      		Ignition switch ON
      		Below 1 V

  1. 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
      W1-1 (D+) - W1-2 (D-)
      		Always
      		Below 1 Ω

  1. Check for short to ground in the circuit.

    1. Measure the resistance.

      Standard resistance:
      Tester Connection
      		Condition
      		Specified Condition
      W1-1 (D+) - Body ground
      		Always
      		1 MΩ or higher
      W1-2 (D-) - Body ground
      		Always
      		1 MΩ or higher

  1. 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
      W1-1 (D+) - W1-2 (D-)
      		Always
      		1 MΩ or higher


NG
Go to step 5
OK


4.CHECK CENTER AIRBAG SENSOR ASSEMBLY


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1800/51 Short In Driver Side Squib Circuit

  1. Connect the connectors to the steering pad and the center airbag sensor assembly.

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

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

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

  1. Turn the ignition switch off.

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

  1. Check the DTCs (YARIS_NCP93 RM000000XFE0D2X.html).

    OK:
    DTC B1800, B1801, B1802, B1803 and 51 are not output.
    HINT:
    DTCs other than DTC B1800, B1801, B1802, B1803 and 51 may be output at this time, but they are not related to this check.


NG
REPLACE CENTER AIRBAG SENSOR ASSEMBLY
OK

USE SIMULATION METHOD TO CHECK

5.CHECK INSTRUMENT PANEL WIRE


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1800/51 Short In Driver Side Squib Circuit

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

  1. Disconnect the instrument panel wire connector from the spiral cable.

  1. 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
      D18-1 (D+) -
      Body ground
      		Ignition switch ON
      		Below 1 V
      D18-2 (D-) -
      Body ground
      		Ignition switch ON
      		Below 1 V

  1. 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
      D18-1 (D+) - D18-2 (D-)
      		Always
      		Below 1 Ω

  1. Check for short to ground in the circuit.

    1. Measure the resistance.

      Standard resistance:
      Tester Connection
      		Condition
      		Specified Condition
      D18-1 (D+) -
      Body ground
      		Always
      		1 MΩ or higher
      D18-2 (D-) -
      Body ground
      		Always
      		1 MΩ or higher

  1. 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
      D18-1 (D+) - D18-2 (D-)
      		Always
      		1 MΩ or higher


NG
REPAIR OR REPLACE INSTRUMENT PANEL WIRE
OK


6.CHECK SPIRAL CABLE


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1800/51 Short In Driver Side Squib Circuit

  1. 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
      W1-1 (D+) - Body ground
      		Ignition switch ON
      		Below 1 V
      W1-2 (D-) - Body ground
      		Ignition switch ON
      		Below 1 V

  1. 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
      W1-1 (D+) - W1-2 (D-)
      		Always
      		Below 1 Ω

  1. Check for short to ground in the circuit.

    1. Measure the resistance.

      Standard resistance:
      Tester Connection
      		Condition
      		Specified Condition
      W1-1 (D+) - Body ground
      		Always
      		1 MΩ or higher
      W1-2 (D-) - Body ground
      		Always
      		1 MΩ or higher

  1. 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
      W1-1 (D+) - W1-2 (D-)
      		Always
      		1 MΩ or higher


NG
REPLACE SPIRAL CABLE
OK

USE SIMULATION METHOD TO CHECK