Last Modified: 11-20-2023 6.11:8.1.0 Doc ID: RM1000000015C2M
Model Year Start: 2018 Model: Camry HV Prod Date Range: [07/2017 -           ]
Title: SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION SYSTEM: B1780; Front Occupant Classification Sensor LH Circuit Malfunction; 2018 - 2024 MY Camry HV [07/2017 -        ]

DTC

B1780

Front Occupant Classification Sensor LH Circuit Malfunction

DESCRIPTION

The front occupant classification sensor LH circuit consists of the occupant detection ECU and front occupant classification sensor LH.

DTC B1780 is stored when a malfunction is detected in the front occupant classification sensor LH circuit.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1780

Front Occupant Classification Sensor LH Circuit Malfunction
  • The occupant detection ECU detects a line short, short to ground or B+, or an open in the front occupant classification sensor LH circuit.
  • Front occupant classification sensor LH malfunction
  • Occupant detection ECU malfunction
  • Front seat wire RH
  • Front occupant classification sensor LH (Front seat adjuster assembly RH)*
  • Occupant detection ECU
  • *: The front occupant classification sensor LH is built into the front seat adjuster assembly RH.

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 2018 - 2019 MY Camry HV [07/2017 - 09/2019]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION 2020 - 2024 MY Camry HV [09/2019 -        ]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION

HINT:

  • When DTC B1650 is stored as a result of troubleshooting for the airbag system, check the DTCs stored in the occupant detection ECU. When DTC B1780 is output, perform troubleshooting for this DTC first.
  • If it is difficult to perform troubleshooting (wire harness inspection), remove the front passenger seat installation bolts to see under the seat cushion.
  • In the above case, lift and hold the seat so that it does not fall down. Hold the seat only as necessary because holding the seat for a long period of time may cause seat rail deformation.

PROCEDURE

1.

CHECK CONNECTORS

(a) Turn the power switch off.

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

(c) Check that the connectors are properly connected to the occupant detection ECU and front occupant classification sensor LH.

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 occupant detection ECU and front occupant classification sensor LH.

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

OK:

The terminals are not deformed or damaged.

NG

REPLACE FRONT SEAT WIRE RH
OK

2.

CHECK FRONT SEAT WIRE RH

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

*1

Front Occupant Classification Sensor LH

*2

Occupant Detection ECU

*3

Front Seat Wire RH

*4

Service Wire

*a

Front view of wire harness connector

(to Occupant Detection ECU)

*b

Front view of wire harness connector

(to Front Occupant Classification Sensor LH)

(b) Turn the power switch on (IG).

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

a7-1 (SVC1) - Body ground

Power switch on (IG)

Below 1 V

a7-3 (SIG1) - Body ground

Power switch on (IG)

Below 1 V

a7-5 (SGD1) - Body ground

Power switch on (IG)

Below 1 V

(d) Turn the power switch off.

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

(f) Using service wires, connect terminals 1 (SVC1) and 3 (SGD1), and terminals 2 (SIG1) and 3 (SGD1) of connector C.

NOTICE:

Do not forcibly insert the service wire into the terminals of the connector when connecting the wire.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

a7-1 (SVC1) - a7-5 (SGD1)

Always

Below 1 Ω

a7-3 (SIG1) - a7-5 (SGD1)

Always

Below 1 Ω

(h) Disconnect the service wires from connector C.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

a7-1 (SVC1) - a7-5 (SGD1)

Always

1 MΩ or higher

a7-3 (SIG1) - a7-5 (SGD1)

Always

1 MΩ or higher

a7-1 (SVC1) - a7-3 (SIG1)

Always

1 MΩ or higher

a7-1 (SVC1) - Body ground

Always

1 MΩ or higher

a7-3 (SIG1) - Body ground

Always

1 MΩ or higher

a7-5 (SGD1) - Body ground

Always

1 MΩ or higher
NG

REPLACE FRONT SEAT WIRE RH
OK

3.

CHECK DTC

(a) Connect the connectors to the occupant detection ECU and front occupant classification sensor LH.

(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 the occupant detection ECU.

Body Electrical > Occupant Detection > Clear DTCs

(e) Clear the DTCs stored in the airbag sensor assembly.

Body Electrical > SRS Airbag > Clear DTCs

(f) Turn the power switch off.

(g) Turn the power switch on (IG), and wait for at least 10 seconds.

(h) Check for DTCs.

Body Electrical > Occupant Detection > Trouble Codes

OK:

DTC B1780 is not output.

HINT:

Codes other than DTC B1780 may be output at this time, but they are not related to this check.

(i) Turn the power switch off.

OK

USE SIMULATION METHOD TO CHECK 2018 MY Camry HV [07/2017 - 09/2018]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING 2019 MY Camry HV [09/2018 - 09/2019]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING 2020 MY Camry HV [09/2019 - 10/2020]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING 2021 MY Camry HV [10/2020 - 08/2021]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING 2022 - 2024 MY Camry HV [08/2021 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING

NG

4.

CHECK OCCUPANT DETECTION ECU

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

(b) Replace the occupant detection ECU with a known good one.

Click here 2018 - 2020 MY Camry HV [07/2017 - 10/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION ECU: REMOVAL 2021 - 2024 MY Camry HV [10/2020 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION ECU: REMOVAL

HINT:

Perform the following inspection using known good parts from another vehicle if possible.

(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 the occupant detection ECU.

Body Electrical > Occupant Detection > Clear DTCs

(f) Clear the DTCs stored in the airbag sensor assembly.

Body Electrical > SRS Airbag > Clear DTCs

(g) Turn the power switch off.

(h) Turn the power switch on (IG), and wait for at least 10 seconds.

(i) Check for DTCs.

Body Electrical > Occupant Detection > Trouble Codes

OK:

DTC B1780 is not output.

HINT:

Codes other than DTC B1780 may be output at this time, but they are not related to this check.

(j) Turn the power switch off.

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

(l) Restore the occupant detection ECU that was installed for testing to its original location.

Click here 2018 - 2020 MY Camry HV [07/2017 - 10/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION ECU: REMOVAL 2021 - 2024 MY Camry HV [10/2020 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION ECU: REMOVAL

NG

GO TO STEP 7

OK

5.

REPLACE OCCUPANT DETECTION ECU

(a) Turn the power switch off.

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

(c) Replace the occupant detection ECU with a new one.

Click here 2018 - 2020 MY Camry HV [07/2017 - 10/2020]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION ECU: REMOVAL 2021 - 2024 MY Camry HV [10/2020 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION ECU: REMOVAL

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

NEXT

6.

PERFORM ZERO POINT CALIBRATION

(a) Using the Techstream, perform Zero Point Calibration.

Click here 2018 - 2024 MY Camry HV [07/2017 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION SYSTEM: INITIALIZATION

NEXT

END

7.

REPLACE FRONT SEAT ADJUSTER ASSEMBLY RH

(a) Turn the power switch off.

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

(c) Replace the front seat adjuster assembly RH.

for Manual Seat: Click here 2018 - 2020 MY Camry HV [07/2017 - 10/2020]; SEAT: FRONT SEAT ASSEMBLY (for Manual Seat): REMOVAL 2021 - 2024 MY Camry HV [10/2020 -        ]; SEAT: FRONT SEAT ASSEMBLY (for Manual Seat): REMOVAL

for Power Seat: Click here 2018 - 2020 MY Camry HV [07/2017 - 10/2020]; SEAT: FRONT SEAT ASSEMBLY (for Power Seat): REMOVAL 2021 - 2024 MY Camry HV [10/2020 -        ]; SEAT: FRONT SEAT ASSEMBLY (for Power Seat): REMOVAL

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

NEXT

8.

PERFORM ZERO POINT CALIBRATION

(a) Using the Techstream, perform Zero Point Calibration.

Click here 2018 - 2024 MY Camry HV [07/2017 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION SYSTEM: INITIALIZATION

NEXT

END