Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VJRK
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 -           ]
Title: SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: B1940/75-B1943/75; Short in Selectable Force Limiter Squib RH Circuit; 2016 - 2020 MY Sienna [12/2015 -        ]

DTC

B1940/75

Short in Selectable Force Limiter Squib RH Circuit

DTC

B1941/75

Open in Selectable Force Limiter Squib RH Circuit

DTC

B1942/75

Short to GND in Selectable Force Limiter Squib RH Circuit

DTC

B1943/75

Short to +B in Selectable Force Limiter Squib RH Circuit

DESCRIPTION

The selectable force limiter squib RH circuit consists of the center airbag sensor assembly and front seat outer belt assembly RH.

The center airbag sensor assembly uses this circuit to deploy the selectable force limiter when deployment conditions are met.

These DTCs are stored when a malfunction is detected in the selectable force limiter squib RH circuit.

DTC No.

DTC Detection Condition

Trouble Area

B1940/ 75
  • The center airbag sensor assembly detects a line short in the selectable force limiter squib RH circuit during primary check.
  • Selectable force limiter squib RH malfunction
  • Center airbag sensor assembly malfunction
  • Floor wire
  • Selectable force limiter squib RH (Front seat outer belt assembly RH)
  • Center airbag sensor assembly

B1941/ 75
  • The center airbag sensor assembly detects an open in the selectable force limiter squib RH circuit.
  • Selectable force limiter squib RH malfunction
  • Center airbag sensor assembly malfunction
  • Floor wire
  • Selectable force limiter squib RH (Front seat outer belt assembly RH)
  • Center airbag sensor assembly

B1942/ 75
  • The center airbag sensor assembly detects a short to ground in the selectable force limiter squib RH circuit.
  • Selectable force limiter squib RH malfunction
  • Center airbag sensor assembly malfunction
  • Floor wire
  • Selectable force limiter squib RH (Front seat outer belt assembly RH)
  • Center airbag sensor assembly

B1943/ 75
  • The center airbag sensor assembly detects a short to B+ in the selectable force limiter squib RH circuit.
  • Selectable force limiter squib RH malfunction
  • Center airbag sensor assembly malfunction
  • Floor wire
  • Selectable force limiter squib RH (Front seat outer belt assembly RH)
  • Center airbag sensor assembly

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work (See page 2016 MY Sienna [12/2015 - 08/2016]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION 2017 - 2020 MY Sienna [08/2016 -        ]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION ).
  • 2 identical squib connectors are connected to the front seat outer belt assembly RH. The selectable force limiter squib RH connector is indicated by the arrow in the illustration.

HINT:

  • Perform the simulation method by selecting check mode (Signal Check) using the Techstream (See page 2016 - 2020 MY Sienna [12/2015 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: CHECK MODE PROCEDURE ).
  • 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 road or rough road (See page 2016 MY Sienna [12/2015 - 08/2016]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING 2017 MY Sienna [08/2016 - 11/2017]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING 2018 - 2020 MY Sienna [11/2017 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING ).

PROCEDURE

1.

CHECK CONNECTORS

(a) Turn the ignition switch off.

Text in Illustration

*1

Front Seat Outer Belt Assembly RH

*2

Center Airbag Sensor Assembly

*3

Floor Wire

(b) 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.

(c) 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 properly connected, reconnect the connectors and proceed to the next inspection.

(d) Disconnect the connectors from the front seat outer belt assembly RH and center airbag sensor assembly.

(e) Check that the terminals of the connectors are not damaged.

OK:

The terminals are not deformed or damaged.

(f) Check that the floor wire connector (on the front seat outer belt assembly RH side) is not damaged.

OK:

The connector locking button is not disengaged, and the claw of the lock is not deformed or damaged.

(g) 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 OUTER BELT ASSEMBLY RH

(a) Connect the connector to the center airbag sensor assembly.

Text in Illustration

*1

Front Seat Outer Belt Assembly RH

*2

Center Airbag Sensor Assembly

*a

Front view of wire harness connector (to Front Seat Outer Belt Assembly RH)

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

CAUTION:

Never connect a tester to the front seat outer belt assembly RH for measurement, as this may lead to a serious injury due to pretensioner deployment.

NOTICE:

  • Do not forcibly insert SST into the terminals of the connector when connecting it.
  • Insert SST straight into the terminals of the connector.

SST: 09843-18061

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

(d) Clear the DTCs stored in memory (See page 2016 - 2020 MY Sienna [12/2015 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: DTC CHECK / CLEAR ).

(e) Turn the ignition switch off.

(f) Turn the ignition switch to ON, and wait for at least 60 seconds.

(g) Check for DTCs (See page 2016 - 2020 MY Sienna [12/2015 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: DTC CHECK / CLEAR ).

OK:

DTC B1940/75, B1941/75, B1942/75 or B1943/75 is not output.

HINT:

Codes other than DTCs B1940/75, B1941/75, B1942/75 and B1943/75 may be output at this time, but they are not related to this check.

(h) Turn the ignition switch off.

(i) 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.

(j) Disconnect SST from connector C.

OK

REPLACE FRONT SEAT OUTER BELT ASSEMBLY RH
NG

3.

CHECK FLOOR WIRE

(a) Disconnect the floor wire from the center airbag sensor assembly.

(b) 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:

Tester Connection

Switch Condition

Specified Condition

L49-1 (SR+) - Body ground

Ignition switch ON

Below 1 V

L49-2 (SR-) - Body ground

Ignition switch ON

Below 1 V

Text in Illustration

*1

Front Seat Outer Belt Assembly RH

*2

Center Airbag Sensor Assembly

*3

Floor Wire

*a

Front view of wire harness connector (to Front Seat Outer Belt Assembly RH)

(4) Turn the ignition switch off.

(5) 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.

(c) Check for an open in the circuit.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

L49-1 (SR+) - L49-2 (SR-)

Always

Below 1 Ω

(d) 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

L49-1 (SR+) - Body ground

Always

1 MΩ or higher

L49-2 (SR-) - Body ground

Always

1 MΩ or higher

(e) Check for a short in the circuit.

(1) Release the activation prevention mechanism built into connector B (See page 2016 - 2020 MY Sienna [12/2015 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: DIAGNOSIS SYSTEM ).

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

L49-1 (SR+) - L49-2 (SR-)

Always

1 MΩ or higher

(3) Restore the released activation prevention mechanism of connector B to the original condition.

NG

REPLACE FLOOR WIRE
OK

4.

CHECK DTC

(a) Connect the connectors to the front seat outer belt assembly RH and center airbag sensor assembly.

Text in Illustration

*1

Front Seat Outer Belt Assembly RH

*2

Center Airbag Sensor Assembly

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

(c) Clear the DTCs stored in memory (See page 2016 - 2020 MY Sienna [12/2015 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: DTC CHECK / CLEAR ).

(d) Turn the ignition switch off.

(e) Turn the ignition switch to ON, and wait for at least 60 seconds.

(f) Check for DTCs (See page 2016 - 2020 MY Sienna [12/2015 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: DTC CHECK / CLEAR ).

OK:

DTC B1940/75, B1941/75, B1942/75 or B1943/75 is not output.

HINT:

Codes other than DTCs B1940/75, B1941/75, B1942/75 and B1943/75 may be output at this time, but they are not related to this check.

OK

USE SIMULATION METHOD TO CHECK
NG

REPLACE CENTER AIRBAG SENSOR ASSEMBLY