Dtc B1825/56 Short In Side Squib Lh Circuit

Vehicle Interior. Corolla. Zre142 Aze141
Supplemental Restraint Systems. Corolla. Zre142 Aze141

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK CONNECTORS

CHECK FRONT SEAT SIDE AIRBAG ASSEMBLY LH (SIDE SQUIB LH)

CHECK FLOOR WIRE (SIDE SQUIB LH CIRCUIT)

CHECK CENTER AIRBAG SENSOR ASSEMBLY

DTC B1825/56 Short in Side Squib LH Circuit

DTC B1826/56 Open in Side Squib LH Circuit

DTC B1827/56 Short to GND in Side Squib LH Circuit

DTC B1828/56 Short to B+ in Side Squib LH Circuit


DESCRIPTION

The side squib LH circuit consists of the center airbag sensor assembly and the front seat side airbag assembly LH.
The circuit instructs the SRS to deploy when deployment conditions are met.
These DTCs are recorded when a malfunction is detected in the side squib LH circuit.

DTC No.
DTC Detection Condition
Trouble Area
B1825/56
  1. The center airbag sensor assembly receives a short circuit signal 5 times in the side squib LH circuit during primary check.
  2. Side squib LH malfunction
  3. Center airbag sensor assembly malfunction
  1. Floor wire
  2. Front seat side airbag assembly LH (Side squib LH)
  3. Center airbag sensor assembly
B1826/56
  1. The center airbag sensor assembly receives an open circuit signal in the side squib LH circuit for 2 seconds.
  2. Side squib LH malfunction
  3. Center airbag sensor assembly malfunction
  1. Floor wire
  2. Front seat side airbag assembly LH (Side squib LH)
  3. Center airbag sensor assembly
B1827/56
  1. The center airbag sensor assembly receives a short circuit to ground signal in the side squib LH circuit for 0.5 seconds.
  2. Side squib LH malfunction
  3. Center airbag sensor assembly malfunction
  1. Floor wire
  2. Front seat side airbag assembly LH (Side squib LH)
  3. Center airbag sensor assembly
B1828/56
  1. The center airbag sensor assembly receives a short circuit to B+ signal in the side squib LH circuit for 0.5 seconds.
  2. Side squib LH malfunction
  3. Center airbag sensor assembly malfunction
  1. Floor wire
  2. Front seat side airbag assembly LH (Side squib LH)
  3. Center airbag sensor assembly

WIRING DIAGRAM


Corolla. Zre142 Aze141.Supplemental Restraint Systems.Airbag System. Dtc B1825/56 Short In Side Squib Lh Circuit


INSPECTION PROCEDURE

HINT:
  1. Perform the simulation method by selecting Check Mode (signal check) using the Techstream (COROLLA_ZRE142 RM000000XFF0COX.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 (COROLLA_ZRE142 RM000000XFD0GSX.html).
1.CHECK CONNECTORS


    Corolla. Zre142 Aze141.Supplemental Restraint Systems.Airbag System. Dtc B1825/56 Short In Side Squib Lh Circuit

  1. Turn the ignition switch off.

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

  1. Check that the connectors are properly connected to the front seat side airbag assembly LH and center 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.

  1. Disconnect the connectors from the front seat side airbag assembly LH and center airbag sensor assembly.

  1. Check that the terminals of the connectors are not damaged.

    OK:
    The terminals are not deformed or damaged.

  1. Check that the short spring for the floor wire with the activation prevention mechanism is not deformed or damaged.

    OK:
    The short spring is not deformed or damaged.


NG
REPLACE FLOOR WIRE
OK


2.CHECK FRONT SEAT SIDE AIRBAG ASSEMBLY LH (SIDE SQUIB LH)


    Corolla. Zre142 Aze141.Supplemental Restraint Systems.Airbag System. Dtc B1825/56 Short In Side Squib Lh Circuit

  1. Connect the connector to the center airbag sensor assembly.

  1. Connect SST (resistance 2.1 Ω) to connector C.

    CAUTION:
    Never connect the tester to the front seat side airbag assembly LH (side squib LH) for measurement, as this may lead to a serious injury due to airbag deployment.
    NOTICE:
    1. Do not forcibly insert SST into the terminals of the connector when connecting.
    2. Insert SST straight into the terminals of the connector.
SST
09843-18061

  1. Connect the cable to the negative (-) battery terminal.

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

  1. Clear the DTCs stored in the memory (COROLLA_ZRE142 RM000000XFE0H1X.html).

  1. Turn the ignition switch off.

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

  1. Check for DTCs (COROLLA_ZRE142 RM000000XFE0H1X.html).

    OK:
    DTC B1825, B1826, B1827, B1828, or 56 is not output.
    HINT:
    Codes other than DTC B1825, B1826, B1827, B1828, and 56 may be output at this time, but they are not related to this check.


NG
Go to step 3
OK

REPLACE FRONT SEAT SIDE AIRBAG ASSEMBLY LH (COROLLA_ZRE142 RM000004HYI00CX.html)

3.CHECK FLOOR WIRE (SIDE SQUIB LH CIRCUIT)


    Corolla. Zre142 Aze141.Supplemental Restraint Systems.Airbag System. Dtc B1825/56 Short In Side Squib Lh Circuit

  1. Turn the ignition switch off.

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

  1. Disconnect SST from connector C.

  1. Disconnect the floor wire from the center airbag sensor assembly.

  1. Check for a short to B+ in the circuit.

    1. Connect the cable to the negative (-) battery terminal.

    2. Turn the ignition switch to ON.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage:
      for Power Seat:
      Tester Connection
      		Switch Condition
      		Specified Condition
      L55-1 (SFL+) - Body ground
      		Ignition switch ON
      		Below 1 V
      L55-2 (SFL-) - Body ground
      		Ignition switch ON
      		Below 1 V
      for Manual Seat:
      Tester Connection
      		Switch Condition
      		Specified Condition
      L15-1 (SFL+) - Body ground
      		Ignition switch ON
      		Below 1 V
      L15-2 (SFL-) - Body ground
      		Ignition switch ON
      		Below 1 V

  1. Check for an open in the circuit.

    1. Turn the ignition switch off.

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

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance:
      for Power Seat:
      Tester Connection
      		Condition
      		Specified Condition
      L55-1 (SFL+) - L55-2 (SFL-)
      		Always
      		Below 1 Ω
      for Manual Seat:
      Tester Connection
      		Condition
      		Specified Condition
      L15-1 (SFL+) - L15-2 (SFL-)
      		Always
      		Below 1 Ω

  1. Check for a short to ground in the circuit.

    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance:
      for Power Seat:
      Tester Connection
      		Condition
      		Specified Condition
      L55-1 (SFL+) - Body ground
      		Always
      		1 MΩ or higher
      L55-2 (SFL-) - Body ground
      		Always
      		1 MΩ or higher
      for Manual Seat:
      Tester Connection
      		Condition
      		Specified Condition
      L15-1 (SFL+) - Body ground
      		Always
      		1 MΩ or higher
      L15-2 (SFL-) - Body ground
      		Always
      		1 MΩ or higher

  1. Check for a short in the circuit.

    1. Release the activation prevention mechanism built into connector B (COROLLA_ZRE142 RM000000XFD0GSX.html).

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance:
      for Power Seat:
      Tester Connection
      		Condition
      		Specified Condition
      L55-1 (SFL+) - L55-2 (SFL-)
      		Always
      		1 MΩ or higher
      for Manual Seat:
      Tester Connection
      		Condition
      		Specified Condition
      L15-1 (SFL+) - L15-2 (SFL-)
      		Always
      		1 MΩ or higher


NG
REPLACE FLOOR WIRE
OK


4.CHECK CENTER AIRBAG SENSOR ASSEMBLY


    Corolla. Zre142 Aze141.Supplemental Restraint Systems.Airbag System. Dtc B1825/56 Short In Side Squib Lh Circuit

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

  1. Connect the connectors to the front seat side airbag assembly LH and the center airbag sensor assembly.

  1. Connect the cable to the negative (-) battery terminal.

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

  1. Clear the DTCs stored in the memory (COROLLA_ZRE142 RM000000XFE0H1X.html).

  1. Turn the ignition switch off.

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

  1. Check for DTCs (COROLLA_ZRE142 RM000000XFE0H1X.html).

    OK:
    DTC B1825, B1826, B1827, B1828, or 56 is not output.
    HINT:
    Codes other than DTC B1825, B1826, B1827, B1828, and 56 may be output at this time, but they are not related to this check.


NG
REPLACE CENTER AIRBAG SENSOR ASSEMBLY (COROLLA_ZRE142 RM000000UWV074X.html)
OK

USE SIMULATION METHOD TO CHECK (COROLLA_ZRE142 RM000000XFD0GSX.html)