Dtc B1820/55 Short In Front Driver Side - Side Squib Circuit


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK FRONT SEAT SIDE AIRBAG RH (SIDE SQUIB RH)

CHECK FLOOR WIRE (SIDE SQUIB RH CIRCUIT)

CHECK CENTER AIRBAG SENSOR ASSEMBLY

DTC B1820/55 Short in Front Driver Side - Side Squib Circuit

DTC B1821/55 Open in Front Driver Side - Side Squib Circuit

DTC B1822/55 Short to GND in Front Driver Side - Side Squib Circuit

DTC B1823/55 Short to B+ in Front Driver Side - Side Squib Circuit


DESCRIPTION

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

DTC Code
Detection Condition
Trouble Area
B1820/55
When all conditions below are met:
  1. The center airbag sensor receives a line short circuit signal 5 times in the driver side - side squib circuit during primary check.
  2. Driver side - side squib malfunction
  3. Center airbag sensor malfunction
  1. Floor wire
  2. Front seat side airbag assembly RH
  3. Center airbag sensor assembly
B1821/55
When all conditions below are met:
  1. The center airbag sensor receives an open circuit signal in the driver side - side squib circuit for 2 seconds.
  2. Driver side - side squib malfunction
  3. Center airbag sensor malfunction
  1. Floor wire
  2. Front seat side airbag assembly RH
  3. Center airbag sensor assembly
B1822/55
When all conditions below are met:
  1. The center airbag sensor receives a short circuit to ground signal in the driver side - side squib circuit for 0.5 seconds.
  2. Driver side - side squib malfunction
  3. Center airbag sensor malfunction
  1. Floor wire
  2. Front seat side airbag assembly RH
  3. Center airbag sensor assembly
B1823/55
When all conditions below are met:
  1. The center airbag sensor receives a short circuit to B+ signal in the driver side - side squib circuit for 0.5 seconds.
  2. Driver side - side squib malfunction
  3. Center airbag sensor malfunction
  1. Floor wire
  2. Front seat side airbag assembly RH
  3. Center airbag sensor assembly

WIRING DIAGRAM


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Supplemental Restraint System.Airbag System. Dtc B1820/55 Short In Front Driver Side - Side Squib Circuit


INSPECTION PROCEDURE

1.CHECK FRONT SEAT SIDE AIRBAG RH (SIDE SQUIB RH)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Supplemental Restraint System.Airbag System. Dtc B1820/55 Short In Front Driver Side - 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 connector from the front seat side airbag RH.

  1. Connect the red wire side of SST (resistance: 2.1 Ω) to connector C.

    CAUTION:
    Never connect the tester to the front seat side airbag RH (side 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 SST.
    2. Insert SST straight into the terminals of the connector.
SST
09843-18061

  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 (Toyota Fortuner RM000000YVY008X.html).

  1. Turn the ignition switch OFF.

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

  1. Check for DTCs (Toyota Fortuner RM000000YVY008X.html).

    OK:
    DTC B1820, B1821, B1822 or B1823 is not output
    HINT:
    Codes other than DTC B1820, B1821, B1822, B1823 may be output at this time, but they are not related to this check.


NG
Go to step 2
OK

REPLACE FRONT SEATBACK ASSEMBLY RH

2.CHECK FLOOR WIRE (SIDE SQUIB RH CIRCUIT)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Supplemental Restraint System.Airbag System. Dtc B1820/55 Short In Front Driver Side - 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 SST from connector C.

  1. Disconnect the connectors from the center airbag sensor.

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

  1. Turn the ignition switch ON.

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    S27-1 (SFR+) - Body ground
    		Ignition switch ON
    		Below 1 V
    S27-2 (SFR-) - Body ground

  1. Turn the ignition switch OFF.

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

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    S27-1 (SFR+) - S27-2 (SFR-)
    		Always
    		Below 1 Ω

  1. Release the activation prevention mechanism built into connector B (Toyota Fortuner RM000000XFD0EGX.html).

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    S27-1 (SFR+) - S27-2 (SFR-)
    		Always
    		1 MΩ or higher
    S27-1 (SFR+) - Body ground
    S27-2 (SFR-) - Body ground


NG
REPLACE FLOOR WIRE
OK


3.CHECK CENTER AIRBAG SENSOR ASSEMBLY
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Supplemental Restraint System.Airbag System. Dtc B1820/55 Short In Front Driver Side - Side Squib Circuit

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

  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 (Toyota Fortuner RM000000YVY008X.html).

  1. Turn the ignition switch OFF.

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

  1. Check for DTCs (Toyota Fortuner RM000000YVY008X.html).

    OK:
    DTC B1820, B1821, B1822 or B1823 is not output
    HINT:
    Codes other than DTC B1820, B1821, B1822, B1823 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