Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM10000000289WF
Model Year Start: 2023 Model: GR Corolla Prod Date Range: [11/2022 -           ]
Title: SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION SYSTEM (for TMMMS Made): B179316; Load Sensor for Occupant Detection System Circuit Voltage Below Threshold; 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 -        ]

DTC

B179316

Load Sensor for Occupant Detection System Circuit Voltage Below Threshold

DESCRIPTION

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B179316

Load Sensor for Occupant Detection System Circuit Voltage Below Threshold

When the detections voltage value below specified value before supplying power to the sensor.
  • Harness or connector
  • Separate type front seat cushion spring assembly RH
  • Airbag sensor assembly

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 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 -        ]; SETUP: WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL: AUTOMATIC LEARNING CHART

  • After replacing the airbag sensor assembly or separate type front seat cushion spring assembly RH, refer to work procedure.

    Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 - 03/2023]; SETUP: WHEN REPLACING OR REMOVING/INSTALLING PARTS: WORK PROCEDURE 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2023 - 08/2023]; SETUP: WHEN REPLACING OR REMOVING/INSTALLING PARTS: WORK PROCEDURE 2024 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [08/2023 -        ]; SETUP: WHEN REPLACING OR REMOVING/INSTALLING PARTS: WORK PROCEDURE

  • Inspect the fuses for circuits related to this system before performing the following procedure.

HINT:

  • 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 CONNECTION OF CONNECTORS

(a) Turn the ignition switch off.

(b) Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 60 seconds.

(c) Check that the connectors are properly connected to the airbag sensor assembly and separate type front seat cushion spring assembly RH.

OK:

The connectors are properly connected.

NG

CONNECT CONNECTORS PROPERLY
OK

2.

CHECK CONNECTORS

(a) Disconnect the airbag sensor assembly connector.

*1

Separate Type Front Seat Cushion Spring Assembly RH

*2

Airbag Sensor Assembly

*3

Wire Harness

(b) Disconnect the separate type front seat cushion spring assembly RH connector.

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

OK:

The terminals are not deformed or damaged.

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

3.

CHECK HARNESS AND CONNECTOR (AIRBAG SENSOR ASSEMBLY - AUXILIARY BATTERY)

(a) Disconnect the airbag sensor assembly connector.

*a

Front view of wire harness connector

(to Airbag Sensor Assembly)

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

(c) Turn the ignition switch to ON.

(d) Operate all components of the electrical systems (defogger, wipers, headlights, heater blower, etc.).

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

I47-36 (IGR) - Body ground

Ignition switch ON

8 to 16 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

CHECK HARNESS AND CONNECTOR (AIRBAG SENSOR ASSEMBLY - SEPARATE TYPE FRONT SEAT CUSHION SPRING ASSEMBLY RH)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

O17-24 (SVC) - Other terminals and body ground

Always

10 kΩ or higher

j6-1 (SVC) - Other terminals and body ground

Always

10 kΩ or higher

j7-1 (SVC) - Other terminals and body ground

Always

10 kΩ or higher

*1

Separate Type Front Seat Cushion Spring Assembly RH

*2

Airbag Sensor Assembly

*3

Wire Harness

*a

Front view of wire harness connector

(to Airbag Sensor Assembly)

*b

Front view of wire harness connector

(to Separate Type Front Seat Cushion Spring Assembly RH (Front Occupant Classification Sensor LH))

*c

Front view of wire harness connector

(to Separate Type Front Seat Cushion Spring Assembly RH (Rear Occupant Classification Sensor LH))
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

CHECK AIRBAG SENSOR ASSEMBLY

(a) Turn the ignition switch off.

*1

Separate Type Front Seat Cushion Spring Assembly RH

*2

Airbag Sensor Assembly

*3

Wire Harness

*a

Front view of wire harness connector

(to Separate Type Front Seat Cushion Spring Assembly RH (Front Occupant Classification Sensor LH))

*b

Front view of wire harness connector

(to Separate Type Front Seat Cushion Spring Assembly RH (Rear Occupant Classification Sensor LH))

(b) Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 60 seconds.

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

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

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

j6-1 (SVC) - Body ground

Ignition switch ON

6.2 V or higher

j7-1 (SVC) - Body ground

Ignition switch ON

6.2 V or higher
OK

REPLACE SEPARATE TYPE FRONT SEAT CUSHION SPRING ASSEMBLY RH

NG

REPLACE AIRBAG SENSOR ASSEMBLY