Last Modified: 01-30-2024 6.11:8.1.0 Doc ID: RM100000001FQQO
Model Year Start: 2019 Model: RAV4 Prod Date Range: [11/2018 - 02/2019]
Title: SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (w/ Occupant Classification System): B1875-B1878; Short in Passenger Side Front Seat Cushion Squib Circuit; 2019 MY RAV4 RAV4 HV [11/2018 - 02/2019]

DTC

B1875

Short in Passenger Side Front Seat Cushion Squib Circuit

DTC

B1876

Open in Passenger Side Front Seat Cushion Squib Circuit

DTC

B1877

Short to GND in Passenger Side Front Seat Cushion Squib Circuit

DTC

B1878

Short to B+ in Passenger Side Front Seat Cushion Squib Circuit

DESCRIPTION

The front seat cushion squib RH circuit consists of the airbag ECU assembly and the front seat cushion airbag assembly RH.

The circuit instructs the SRS to deploy when deployment conditions are met.

These DTCs are recorded when a malfunction is detected in the front seat cushion squib RH circuit.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Test Mode / Check Mode

B1875

Short in Passenger Side Front Seat Cushion Squib Circuit

One of the following conditions is met:

  • The airbag ECU assembly detects a line short circuit signal 5 times in the front seat cushion squib RH circuit during primary check.
  • A front seat cushion airbag assembly RH malfunction.
  • An airbag ECU assembly malfunction.
  • Floor wire
  • Front seat cushion airbag assembly RH
  • Airbag ECU assembly

Comes on

Comes on

B1876

Open in Passenger Side Front Seat Cushion Squib Circuit

One of the following conditions is met:

  • The airbag ECU assembly detects an open circuit signal in the front seat cushion squib RH circuit for 2 seconds.
  • A front seat cushion airbag assembly RH malfunction.
  • An airbag ECU assembly malfunction.
  • Floor wire
  • Front seat cushion airbag assembly RH
  • Airbag ECU assembly

Comes on

Comes on

B1877

Short to GND in Passenger Side Front Seat Cushion Squib Circuit

One of the following conditions is met:

  • The airbag ECU assembly detects a short circuit to ground signal in the front seat cushion squib RH circuit for 0.5 seconds.
  • A front seat cushion airbag assembly RH malfunction.
  • An airbag ECU assembly malfunction.
  • Floor wire
  • Front seat cushion airbag assembly RH
  • Airbag ECU assembly

Comes on

Comes on

B1878

Short to B+ in Passenger Side Front Seat Cushion Squib Circuit

One of the following conditions is met:

  • The airbag ECU assembly detects a short circuit to B+ signal in the front seat cushion squib RH circuit for 0.5 seconds.
  • A front seat cushion airbag assembly RH malfunction.
  • An airbag ECU assembly malfunction.
  • Floor wire
  • Front seat cushion airbag assembly RH
  • Airbag ECU assembly

Comes on

Comes on

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.

    Click here 2019 MY RAV4 RAV4 HV [11/2018 - 02/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

  • When disconnecting the cable from the negative (-) battery terminal while performing repairs, some systems need to be initialized after the cable is reconnected.

    Click here 2019 MY RAV4 RAV4 HV [11/2018 - 02/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

  • After replacing the airbag ECU assembly, refer to initialization.

    Click here 2019 MY RAV4 RAV4 HV [11/2018 - 02/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

HINT:

To perform the simulation method, enter check mode (signal check) with the Techstream (Click here 2019 - 2020 MY RAV4 RAV4 HV [11/2018 - 08/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (w/ Occupant Classification System): CHECK MODE PROCEDURE ), and then wiggle each connector of the airbag system or drive the vehicle on various types of road (Click here 2019 - 2024 MY RAV4 RAV4 HV [11/2018 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING ).

PROCEDURE

1.

CHECK CONNECTORS

(a) Turn the ignition switch off.

*1

Front Seat Cushion Airbag Assembly RH

*2

Airbag ECU Assembly

*3

Floor Wire

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

(c) Check that the connectors are properly connected to the front seat cushion airbag assembly RH and airbag ECU 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 cushion airbag assembly RH and airbag ECU assembly.

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

OK:

The terminals are not deformed or damaged.

(f) Check that the short springs of the activation prevention mechanism of the floor wire connector are not deformed or damaged.

OK:

The short springs are not deformed or damaged.

NG

REPLACE FLOOR WIRE
OK

2.

CHECK FRONT SEAT CUSHION AIRBAG ASSEMBLY RH

(a) Connect the connector to the airbag ECU assembly.

*1

Front Seat Cushion Airbag Assembly RH

*2

Airbag ECU Assembly

*3

SST

*a

Front view of wire harness connector

(to Front Seat Cushion Airbag Assembly RH)

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

CAUTION:

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

NOTICE:

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

SST: 09843-18061

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

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

(e) Clear the DTCs stored in memory.

Click here 2019 - 2020 MY RAV4 RAV4 HV [11/2018 - 08/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (w/ Occupant Classification System): DTC CHECK / CLEAR

Body Electrical > SRS Airbag > Clear DTCs

(f) Turn the ignition switch off.

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

(h) Check for DTCs.

Click here 2019 - 2020 MY RAV4 RAV4 HV [11/2018 - 08/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (w/ Occupant Classification System): DTC CHECK / CLEAR

Body Electrical > SRS Airbag > Trouble Codes

HINT:

Codes other than DTC B1875, B1876, B1877 and B1878 may be output at this time, but they are not related to this check.

(i) Turn the ignition switch off.

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

(k) Disconnect SST from connector C.

DTCs B1875, B1876, B1877 and B1878 are not output

REPLACE FRONT SEAT CUSHION AIRBAG ASSEMBLY RH

DTC B1875, B1876, B1877 or B1878 is output

3.

CHECK FLOOR WIRE

(a) Disconnect the floor wire from the airbag ECU assembly.

*1

Front Seat Cushion Airbag Assembly RH

*2

Airbag ECU Assembly

*3

Floor Wire

*a

Front view of wire harness connector

(to Front Seat Cushion Airbag Assembly RH)

Release the activation prevention mechanism

(b) Check for a short to B+ in the circuit.

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

(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

M19-2 (FCP+) - Body ground

Ignition switch ON

Below 1 V

M19-1 (FCP-) - Body ground

Ignition switch ON

Below 1 V

(4) Turn the ignition switch off.

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

(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

M19-2 (FCP+) - M19-1 (FCP-)

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

M19-2 (FCP+) - Body ground

Always

1 MΩ or higher

M19-1 (FCP-) - 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.

Click here 2019 - 2020 MY RAV4 RAV4 HV [11/2018 - 08/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (w/ Occupant Classification System): SYSTEM DESCRIPTION

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

M19-2 (FCP+) - M19-1 (FCP-)

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 cushion airbag assembly RH and airbag ECU assembly.

*1

Front Seat Cushion Airbag Assembly RH

*2

Airbag ECU Assembly

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

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

(d) Clear the DTCs stored in memory.

Click here 2019 - 2020 MY RAV4 RAV4 HV [11/2018 - 08/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (w/ Occupant Classification System): DTC CHECK / CLEAR

Body Electrical > SRS Airbag > Clear DTCs

(e) Turn the ignition switch off.

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

(g) Check for DTCs.

Click here 2019 - 2020 MY RAV4 RAV4 HV [11/2018 - 08/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (w/ Occupant Classification System): DTC CHECK / CLEAR

Body Electrical > SRS Airbag > Trouble Codes

HINT:

Codes other than DTC B1875, B1876, B1877 and B1878 may be output at this time, but they are not related to this check.

DTCs B1875, B1876, B1877 and B1878 are not output

USE SIMULATION METHOD TO CHECK

DTC B1875, B1876, B1877 or B1878 is output

REPLACE AIRBAG ECU ASSEMBLY