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DTC    B1900/73    Short in Front Pretensioner Squib RH Circuit

DTC    B1901/73    Open in Front Pretensioner Squib RH Circuit

DTC    B1902/73    Short to GND in Front Pretensioner Squib RH Circuit

DTC    B1903/73    Short to B+ in Front Pretensioner Squib RH Circuit

for Preparation Click here


DESCRIPTION

The front pretensioner squib RH circuit consists of the center airbag sensor assembly and front seat outer belt assembly RH.
This circuit instructs SRS to deploy when deployment conditions are met.
These DTCs are stored when a malfunction is detected in the front pretensioner squib RH circuit.

DTC No.
DTC Detection Condition
Trouble Area
B1900/73
  1. The center airbag sensor assembly receives a line short circuit signal in the front pretensioner squib RH circuit during primary check.
  2. Front pretensioner squib RH malfunction
  3. Center airbag sensor assembly malfunction
  1. No. 2 floor wire
  2. Front seat outer belt assembly RH (Front pretensioner squib RH)
  3. Center airbag sensor assembly
B1901/73
  1. The center airbag sensor assembly receives an open circuit signal in the front pretensioner squib RH circuit.
  2. Front pretensioner squib RH malfunction
  3. Center airbag sensor assembly malfunction
  1. No. 2 floor wire
  2. Front seat outer belt assembly RH (Front pretensioner squib RH)
  3. Center airbag sensor assembly
B1902/73
  1. The center airbag sensor assembly receives a short circuit to ground signal in the front pretensioner squib RH circuit.
  2. Front pretensioner squib RH malfunction
  3. Center airbag sensor assembly malfunction
  1. No. 2 floor wire
  2. Front seat outer belt assembly RH (Front pretensioner squib RH)
  3. Center airbag sensor assembly
B1903/73
  1. The center airbag sensor assembly receives a short circuit to B+ signal in the front pretensioner squib RH circuit.
  2. Front pretensioner squib RH malfunction
  3. Center airbag sensor assembly malfunction
  1. No. 2 floor wire
  2. Front seat outer belt assembly RH (Front pretensioner squib RH)
  3. Center airbag sensor assembly

WIRING DIAGRAM


C198980E24


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


    C165140E39

  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 outer belt assembly RH 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 outer belt assembly RH 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 No. 2 floor wire connector (on the front seat outer belt assembly RH side) is not damaged.

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

  1. Check that the short spring for the No. 2 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
    		Front Pretensioner Squib RH
    *2
    		Center Airbag Sensor Assembly
    *3
    		No. 2 Floor Wire



NG
REPLACE NO. 2 FLOOR WIRE
OK


2.CHECK FRONT SEAT OUTER BELT ASSEMBLY RH (FRONT PRETENSIONER SQUIB RH)


    C190159E09

  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 outer belt assembly RH (front pretensioner squib RH) 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 B1900, B1901, B1902, B1903 or 73 is not output.

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

    HINT:
    Codes other than DTCs B1900, B1901, B1902, B1903 and 73 may be output at this time, but they are not related to this check.



NG
Go to step 3
OK

REPLACE FRONT SEAT OUTER BELT ASSEMBLY RH (Click here)  

3.CHECK NO. 2 FLOOR WIRE (FRONT PRETENSIONER SQUIB RH CIRCUIT)


    C171090E16

  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 No. 2 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
      S6-1 (R+) - Body ground
      		Power switch on (IG)
      		Below 1 V
      S6-2 (R-) - 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
      S6-1 (R+) - S6-2 (R-)
      		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
      S6-1 (R+) - Body ground
      		Always
      		1 MΩ or higher
      S6-2 (R-) - 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
      S6-1 (R+) - S6-2 (R-)
      		Always
      		1 MΩ or higher

      Text in Illustration 
      *1
      		Front Pretensioner Squib RH
      *2
      		Center Airbag Sensor Assembly
      *3
      		No. 2 Floor Wire
      *4
      		Front view of wire harness connector
      (to Front Seat Outer Belt Assembly RH)
      *5
      		Connector C



NG
REPLACE NO. 2 FLOOR WIRE
OK


4.CHECK CENTER AIRBAG SENSOR ASSEMBLY


    C170976E05

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

  1. Connect the connectors to the front seat outer belt assembly RH 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 B1900, B1901, B1902, B1903 or 73 is not output.

    Text in Illustration 
    *1
    		Front Pretensioner Squib RH
    *2
    		Center Airbag Sensor Assembly

    HINT:
    Codes other than DTCs B1900, B1901, B1902, B1903 and 73 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)