Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001AR80
Model Year Start: 2019 Model: Avalon HV Prod Date Range: [04/2018 -           ]
Title: SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (for HV Model): B1810-B1813; Short in D Squib (Dual Stage - 2nd Step) Circuit; 2019 - 2022 MY Avalon HV [04/2018 -        ]

DTC

B1810

Short in D Squib (Dual Stage - 2nd Step) Circuit

DTC

B1811

Open in D Squib (Dual Stage - 2nd Step) Circuit

DTC

B1812

Short in D Squib (Dual Stage - 2nd Step) Circuit (to Ground)

DTC

B1813

Short in D Squib (Dual Stage - 2nd Step) Circuit (to +B)

DESCRIPTION

The driver squib 2nd step circuit consists of the airbag ECU assembly, spiral cable sub-assembly and horn button assembly.

The airbag ECU 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 squib 2nd step circuit.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Test Mode / Check Mode

B1810

Short in D Squib (Dual Stage - 2nd Step) Circuit

  • The airbag ECU assembly detects a line short in the driver squib 2nd step circuit during the primary check.
  • Spiral cable sub-assembly malfunction
  • Driver squib 2nd step malfunction
  • Airbag ECU assembly malfunction
  • Instrument panel wire
  • Spiral cable sub-assembly
  • Driver squib 2nd step (Horn button assembly)
  • Airbag ECU assembly

Comes on

Applies to check mode

B1811

Open in D Squib (Dual Stage - 2nd Step) Circuit

  • The airbag ECU assembly detects an open in the driver squib 2nd step circuit.
  • Spiral cable sub-assembly malfunction
  • Driver squib 2nd step malfunction
  • Airbag ECU assembly malfunction
  • Instrument panel wire
  • Spiral cable sub-assembly
  • Driver squib 2nd step (Horn button assembly)
  • Airbag ECU assembly

Comes on

Applies to check mode

B1812

Short in D Squib (Dual Stage - 2nd Step) Circuit (to Ground)

  • The airbag ECU assembly detects a short to ground in the driver squib 2nd step circuit.
  • Spiral cable sub-assembly malfunction
  • Driver squib 2nd step malfunction
  • Airbag ECU assembly malfunction
  • Instrument panel wire
  • Spiral cable sub-assembly
  • Driver squib 2nd step (Horn button assembly)
  • Airbag ECU assembly

Comes on

Applies to check mode

B1813

Short in D Squib (Dual Stage - 2nd Step) Circuit (to +B)

  • The airbag ECU assembly detects a short to B+ in the driver squib 2nd step circuit.
  • Spiral cable sub-assembly malfunction
  • Driver squib 2nd step malfunction
  • Airbag ECU assembly malfunction
  • Instrument panel wire
  • Spiral cable sub-assembly
  • Driver squib 2nd step (Horn button assembly)
  • Airbag ECU assembly

Comes on

Applies to check mode

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

Click here 2019 - 2022 MY Avalon Avalon HV [04/2018 -        ]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION

HINT:

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

    Click here 2019 - 2022 MY Avalon HV [04/2018 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (for HV Model): 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 - 2022 MY Avalon Avalon HV [04/2018 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING

PROCEDURE

1.

CHECK CONNECTORS

(a) Turn the power switch off.

*1

Horn Button Assembly

*2

Spiral Cable Sub-assembly

*3

Airbag ECU Assembly

*4

Instrument Panel Wire

(b) Disconnect the cable from the negative (-) auxiliary battery terminal.

CAUTION:

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

(c) Check that the connectors are properly connected to the horn button assembly, spiral cable sub-assembly 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 horn button assembly, spiral cable sub-assembly 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 spiral cable sub-assembly connector (on the horn button 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 mechanisms of the instrument panel wire connector and spiral cable sub-assembly connector are not deformed or damaged.

OK:

The short springs are not deformed or damaged.

NG

REPLACE WIRE HARNESS

OK

2.

CHECK HORN BUTTON ASSEMBLY

(a) Connect the instrument panel wire to the airbag ECU assembly and spiral cable sub-assembly.

*1

Horn Button Assembly

*2

Spiral Cable Sub-assembly

*3

Airbag ECU Assembly

*a

Front view of wire harness connector

(to Horn Button Assembly)

*b

Color: Black

(b) Connect SST (resistance 2.1 Ω) to connector E (black connector).

CAUTION:

Never connect a tester to the horn button 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 (-) auxiliary battery terminal.

(d) Turn the power switch on (IG), and wait for at least 60 seconds.

(e) Clear the DTCs stored in memory.

Body Electrical > SRS Airbag > Clear DTCs

(f) Turn the power switch off.

(g) Turn the power switch on (IG), and wait for at least 60 seconds.

(h) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

OK:

DTC B1810, B1811, B1812 or B1813 is not output.

HINT:

Codes other than DTCs B1810, B1811, B1812 and B1813 may be output at this time, but they are not related to this check.

(i) Turn the power switch off.

(j) Disconnect the cable from the negative (-) auxiliary battery terminal.

CAUTION:

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

(k) Disconnect SST from connector E.

OK

REPLACE HORN BUTTON ASSEMBLY 2019 - 2020 MY Avalon Avalon HV [04/2018 - 08/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: STEERING PAD: REMOVAL 2021 MY Avalon Avalon HV [08/2020 - 08/2021]; SUPPLEMENTAL RESTRAINT SYSTEMS: STEERING PAD: REMOVAL 2022 MY Avalon Avalon HV [08/2021 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: STEERING PAD: REMOVAL

NG

3.

CHECK DRIVER SQUIB 2ND STEP CIRCUIT

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

*1

Horn Button Assembly

*2

Spiral Cable Sub-assembly

*3

Airbag ECU Assembly

*a

Front view of wire harness connector

(to Horn Button Assembly)

*b

Color: Black

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

(1) Connect the cable to the negative (-) auxiliary 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

Condition

Specified Condition

z6-2 (D2+) - Body ground

Power switch on (IG)

Below 1 V

z6-1 (D2-) - Body ground

Power switch on (IG)

Below 1 V

(4) Turn the power switch off.

(5) Disconnect the cable from the negative (-) auxiliary battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) auxiliary 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

z6-2 (D2+) - z6-1 (D2-)

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

z6-2 (D2+) - Body ground

Always

1 MΩ or higher

z6-1 (D2-) - 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 - 2022 MY Avalon HV [04/2018 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (for HV Model): SYSTEM DESCRIPTION

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

z6-2 (D2+) - z6-1 (D2-)

Always

1 MΩ or higher

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

NG

GO TO STEP 5

OK

4.

CHECK DTC

(a) Connect the connectors to the horn button assembly and airbag ECU assembly.

*1

Horn Button Assembly

*2

Spiral Cable Sub-assembly

*3

Airbag ECU Assembly

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

(c) Turn the power switch on (IG), and wait for at least 60 seconds.

(d) Clear the DTCs stored in memory.

Body Electrical > SRS Airbag > Clear DTCs

(e) Turn the power switch off.

(f) Turn the power switch on (IG), and wait for at least 60 seconds.

(g) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

OK:

DTC B1810, B1811, B1812 or B1813 is not output.

HINT:

Codes other than DTCs B1810, B1811, B1812 and B1813 may be output at this time, but they are not related to this check.

OK

USE SIMULATION METHOD TO CHECK

NG

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5.

CHECK INSTRUMENT PANEL WIRE

(a) Disconnect the instrument panel wire from the spiral cable sub-assembly.

*1

Horn Button Assembly

*2

Spiral Cable Sub-assembly

*3

Airbag ECU Assembly

*4

Instrument Panel Wire

*a

Front view of wire harness connector

(to Spiral Cable Sub-assembly)

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

(1) Connect the cable to the negative (-) auxiliary 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

Condition

Specified Condition

G18-4 (D2+) - Body ground

Power switch on (IG)

Below 1 V

G18-3 (D2-) - Body ground

Power switch on (IG)

Below 1 V

(4) Turn the power switch off.

(5) Disconnect the cable from the negative (-) auxiliary battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) auxiliary 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

G18-4 (D2+) - G18-3 (D2-)

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

G18-4 (D2+) - Body ground

Always

1 MΩ or higher

G18-3 (D2-) - 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 - 2022 MY Avalon HV [04/2018 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (for HV Model): SYSTEM DESCRIPTION

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G18-4 (D2+) - G18-3 (D2-)

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

6.

CHECK SPIRAL CABLE SUB-ASSEMBLY

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

(1) Connect the cable to the negative (-) auxiliary 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

Condition

Specified Condition

z6-2 (D2+) - Body ground

Power switch on (IG)

Below 1 V

z6-1 (D2-) - Body ground

Power switch on (IG)

Below 1 V

(4) Turn the power switch off.

(5) Disconnect the cable from the negative (-) auxiliary battery terminal.

CAUTION:

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

*1

Horn Button Assembly

*2

Spiral Cable Sub-assembly

*3

Airbag ECU Assembly

*4

Instrument Panel Wire

*a

Front view of wire harness connector

(to Horn Button Assembly)

*b

Color: Black

(b) 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

z6-2 (D2+) - z6-1 (D2-)

Always

Below 1 Ω

(c) 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

z6-2 (D2+) - Body ground

Always

1 MΩ or higher

z6-1 (D2-) - Body ground

Always

1 MΩ or higher

(d) Check for a short in the circuit.

(1) Release the activation prevention mechanism built into connector D.

Click here 2019 - 2022 MY Avalon HV [04/2018 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM (for HV Model): SYSTEM DESCRIPTION

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

z6-2 (D2+) - z6-1 (D2-)

Always

1 MΩ or higher

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

OK

USE SIMULATION METHOD TO CHECK

NG

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