Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM10000000277A1
Model Year Start: 2023 Model: GR Corolla Prod Date Range: [09/2022 - 11/2022]
Title: SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (for TMMMS Made): B1860-B1863; Short in Knee Airbag (D Side) Squib Circuit; 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]

DTC

B1860

Short in Knee Airbag (D Side) Squib Circuit

DTC

B1861

Open in Knee Airbag (D Side) Squib Circuit

DTC

B1862

Short in Knee Airbag (D Side) Squib Circuit (to Ground)

DTC

B1863

Short in Knee Airbag (D Side) Squib Circuit (to +B)

DESCRIPTION

The driver side knee airbag squib circuit consists of the airbag sensor assembly and lower No. 1 instrument panel airbag assembly.

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

These DTCs are stored when a malfunction is detected in the driver side knee airbag squib circuit.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Test Mode / Check Mode

B1860

Short in Knee Airbag (D Side) Squib Circuit
  • The airbag sensor assembly detects a line short in the driver side knee airbag squib during the primary check.
  • Driver side knee airbag squib malfunction
  • Airbag sensor assembly malfunction
  • Instrument panel wire
  • Driver side knee airbag squib (Lower No. 1 instrument panel airbag assembly)
  • Airbag sensor assembly

Comes on

Applies to check mode

B1861

Open in Knee Airbag (D Side) Squib Circuit
  • The airbag sensor assembly detects an open in the driver side knee airbag squib.
  • Driver side knee airbag squib malfunction
  • Airbag sensor assembly malfunction
  • Instrument panel wire
  • Driver side knee airbag squib (Lower No. 1 instrument panel airbag assembly)
  • Airbag sensor assembly

Comes on

Applies to check mode

B1862

Short in Knee Airbag (D Side) Squib Circuit (to Ground)
  • The airbag sensor assembly detects a short to ground in the driver side knee airbag squib.
  • Driver side knee airbag squib malfunction
  • Airbag sensor assembly malfunction
  • Instrument panel wire
  • Driver side knee airbag squib (Lower No. 1 instrument panel airbag assembly)
  • Airbag sensor assembly

Comes on

Applies to check mode

B1863

Short in Knee Airbag (D Side) Squib Circuit (to +B)
  • The airbag sensor assembly detects a short to B+ in the driver side knee airbag squib.
  • Driver side knee airbag squib malfunction
  • Airbag sensor assembly malfunction
  • Instrument panel wire
  • Driver side knee airbag squib (Lower No. 1 instrument panel airbag assembly)
  • Airbag sensor assembly

Comes on

Applies to check mode

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.

    Click here 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 -        ]; SETUP: WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL: BEFORE DISCONNECTING BATTERY

    HINT:

    When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.

    Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; SETUP: WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL: AUTOMATIC LEARNING CHART

HINT:

  • Perform the simulation method by selecting check mode (Signal Check) using the Techstream.

    Click here 2020 - 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 11/2022]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (for TMMMS Made): 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.

    Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING

PROCEDURE

1.

CHECK CONNECTORS

(a) Turn the ignition switch off.

*1

Lower No. 1 Instrument Panel Airbag Assembly

*2

Airbag Sensor Assembly

*3

Instrument Panel 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 lower No. 1 instrument panel airbag assembly and 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 lower No. 1 instrument panel airbag assembly and airbag sensor 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 instrument panel wire connector (on the lower No. 1 instrument panel airbag assembly side) is not loose, deformed or damaged.

OK:

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

(g) Check that the short springs of the activation prevention mechanism of the instrument panel wire connector are not deformed or damaged.

OK:

The short springs are not deformed or damaged.

NG

REPLACE INSTRUMENT PANEL WIRE
OK

2.

CHECK LOWER NO. 1 INSTRUMENT PANEL AIRBAG ASSEMBLY

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

*1

Lower No. 1 Instrument Panel Airbag Assembly

*2

Airbag Sensor Assembly

*a

Front view of wire harness connector

(to Lower No. 1 Instrument Panel Airbag Assembly)

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

CAUTION:

Never connect a tester to the lower No. 1 instrument panel airbag assembly 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 it.
  • Insert SST straight into the terminals of the connector.

SST: 09843-18061

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

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

(e) Clear the DTCs stored in memory.

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.

Body Electrical > SRS Airbag > Trouble Codes

OK:

DTC B1860, B1861, B1862 or B1863 is not output.

HINT:

Codes other than DTCs B1860, B1861, B1862 and B1863 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.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(k) Disconnect SST from connector C.

OK

REPLACE LOWER NO. 1 INSTRUMENT PANEL AIRBAG ASSEMBLY

NG

3.

CHECK INSTRUMENT PANEL WIRE

(a) Disconnect the instrument panel wire from the airbag sensor assembly.

*1

Lower No. 1 Instrument Panel Airbag Assembly

*2

Airbag Sensor Assembly

*3

Instrument Panel Wire

*a

Front view of wire harness connector

(to Lower No. 1 Instrument Panel Airbag 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

Condition

Specified Condition

I23-1 (DK+) - Body ground

Ignition switch ON

Below 1 V

I23-2 (DK-) - Body ground

Ignition switch ON

Below 1 V

(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

I23-1 (DK+) - I23-2 (DK-)

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

I23-1 (DK+) - Body ground

Always

1 MΩ or higher

I23-2 (DK-) - 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 2021 - 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 11/2022]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (for TMMMS Made): SYSTEM DESCRIPTION

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

I23-1 (DK+) - I23-2 (DK-)

Always

1 MΩ or higher

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

NG

REPLACE INSTRUMENT PANEL WIRE
OK

4.

CHECK DTC

(a) Connect the connectors to the lower No. 1 instrument panel airbag assembly and airbag sensor assembly.

*1

Lower No. 1 Instrument Panel Airbag Assembly

*2

Airbag Sensor Assembly

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

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

(d) Clear the DTCs stored in memory.

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.

Body Electrical > SRS Airbag > Trouble Codes

OK:

DTC B1860, B1861, B1862 or B1863 is not output.

HINT:

Codes other than DTCs B1860, B1861, B1862 and B1863 may be output at this time, but they are not related to this check.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE AIRBAG SENSOR ASSEMBLY