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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

for Preparation Click here


DESCRIPTION

The side squib LH circuit consists of the center airbag sensor assembly and front seat side airbag assembly LH.
The circuit instructs SRS to deploy when deployment conditions are met.
These DTCs are stored 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 line short circuit signal 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.
  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.
  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.
  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


C210621E04


INSPECTION PROCEDURE

HINT:
  1. Perform the simulation method by selecting check mode (Signal Check) using the intelligent tester (Click here).
  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 (Click here).

1.CHECK CONNECTORS


    C165141E26

  1. Turn the power switch off.

  1. 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.

  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.

    Text in Illustration 
    *1
    		Side Squib LH
    *2
    		Center Airbag Sensor Assembly
    *3
    		Floor Wire



NG
REPLACE FLOOR WIRE
OK


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


    C210791E01

  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 power switch on (IG), and wait for at least 60 seconds.

  1. Clear the DTCs stored in the memory (Click here).

  1. Turn the power switch off.

  1. Turn the power switch on (IG), and wait for at least 60 seconds.

  1. Check for DTCs (Click here).

    OK:
    DTC B1825, B1826, B1827, B1828 or 56 is not output.

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

    Text in Illustration 
    *1
    		Side Squib LH
    *2
    		Center Airbag Sensor Assembly
    *3
    		Front view of wire harness connector
    (to Front Seat Side Airbag Assembly LH)
    *4
    		Connector C



NG
Go to step 3
OK

REPLACE FRONT SEAT SIDE AIRBAG ASSEMBLY LH (Click here)  

3.CHECK FLOOR WIRE (SIDE SQUIB LH CIRCUIT)
C157616E09

  1. Turn the power switch off.

  1. 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.

  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 power switch on (IG).

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

      Standard Voltage:
      Tester Connection
      		Switch Condition
      		Specified Condition
      R3-1 (SFL+) - Body ground
      		Power switch on (IG)
      		Below 1 V
      R3-2 (SFL-) - Body ground
      		Power switch on (IG)
      		Below 1 V

  1. Check for an open in the circuit.

    1. Turn the power switch off.

    2. 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.

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      R3-1 (SFL+) - R3-2 (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:
      Tester Connection
      		Condition
      		Specified Condition
      R3-1 (SFL+) - Body ground
      		Always
      		1 MΩ or higher
      R3-2 (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 (Click here).

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      R3-1 (SFL+) - R3-2 (SFL-)
      		Always
      		1 MΩ or higher

      Text in Illustration 
      *1
      		Side Squib LH
      *2
      		Center Airbag Sensor Assembly
      *3
      		Floor Wire
      *4
      		Front view of wire harness connector
      (to Front Seat Side Airbag Assembly LH)
      *5
      		Connector C



NG
REPLACE FLOOR WIRE
OK


4.CHECK CENTER AIRBAG SENSOR ASSEMBLY


    C170972E08

  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 center airbag sensor assembly.

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

  1. Turn the power switch on (IG), and wait for at least 60 seconds.

  1. Clear the DTCs stored in the memory (Click here).

  1. Turn the power switch off.

  1. Turn the power switch on (IG), and wait for at least 60 seconds.

  1. Check for DTCs (Click here).

    OK:
    DTC B1825, B1826, B1827, B1828 or 56 is not output.

    Text in Illustration 
    *1
    		Side Squib LH
    *2
    		Center Airbag Sensor Assembly

    HINT:
    Codes other than DTCs 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 (Click here)
OK

USE SIMULATION METHOD TO CHECK (Click here)