Last Modified: 12-11-2024 6.11:8.1.0 Doc ID: RM100000002QL18
Model Year Start: 2025 Model: GR Corolla Prod Date Range: [09/2024 -           ]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model without Electric Parking Brake System TMC Made): VSC OFF Switch Circuit; 2025 MY Corolla Corolla Hatchback GR Corolla [09/2024 -        ]

VSC OFF Switch Circuit

DESCRIPTION

The skid control ECU (brake actuator assembly) is connected to the combination meter assembly via CAN communication.

Pressing the VSC OFF switch (combination switch assembly) turns off TRAC operation, and pressing and holding this switch turns off TRAC and VSC operation. If TRAC and VSC operations are turned off, the TRAC OFF indicator light and the VSC OFF indicator light will come on.

Pressing the VSC OFF switch (combination switch assembly) when in AWD mode changes the mode to EXPERT mode*. In EXPERT mode, the TRAC OFF indicator light and VSC OFF indicator light illuminate and EXPERT is displayed on the multi-information display.

HINT:

*: EXPERT mode performs control to help prevent the vehicle from spinning during oversteer maneuvers.

WIRING DIAGRAM

PROCEDURE

1.

READ VALUE USING GTS (TRAC/VSC OFF MODE)

(a) Check that the indicator light and mode condition on the GTS change according to VSC OFF switch (combination switch assembly) operation.

Chassis > Brake/EPB > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

TRC(TRAC)/VSC OFF Mode

TRAC/VSC off mode

Normal mode (TRC(TRAC) ON/VSC ON) / TRC(TRAC) OFF mode (TRC(TRAC) OFF/VSC ON) / VSC expert mode (VSC expert mode MID ON) / VSC OFF mode (TRC(TRAC) OFF/VSC OFF)

Normal mode (TRC(TRAC) ON/VSC ON): Normal mode

TRC(TRAC) OFF mode (TRC(TRAC) OFF/VSC ON): TRAC off mode

VSC expert mode (VSC expert mode MID ON): VSC expert mode

VSC OFF mode (TRC(TRAC) OFF/VSC OFF): VSC off mode

-

Chassis > Brake/EPB > Data List

Tester Display

TRC(TRAC)/VSC OFF Mode

Standard:

Switch Operation

Mode Condition Display

TRAC OFF Indicator Light

VSC OFF Indicator Light

Not pressed

Normal mode (TRC(TRAC) ON/VSC ON)

Does not come on

Does not come on

Pressing the VSC OFF switch (combination switch assembly)

TRC(TRAC) OFF mode (TRC(TRAC) OFF/VSC ON)

Comes on

Does not come on

Pressing and holding the VSC OFF switch (combination switch assembly)

VSC OFF mode (TRC(TRAC) OFF/VSC OFF)

Comes on

Comes on

Result

Proceed to

Indicator light and mode condition display do not change.

A

Mode condition display is normal, but indicator light does not change.

B

Indicator light and mode condition display are normal.

C
B

INSPECT METER / GAUGE SYSTEM

C

USE SIMULATION METHOD TO CHECK

A

2.

INSPECT COMBINATION SWITCH ASSEMBLY

(a) Turn the ignition switch off.

(b) Inspect the VSC OFF switch (combination switch assembly).

Click here 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VSC OFF SWITCH: INSPECTION

OK:

The VSC OFF switch (combination switch assembly) is normal.

NG

REPLACE COMBINATION SWITCH ASSEMBLY

OK

3.

CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - COMBINATION SWITCH ASSEMBLY)

(a) Make sure that there is no looseness at the locking part and the connecting part of the connectors.

OK:

The connector is securely connected.

(b) Disconnect the A140 skid control ECU (brake actuator assembly) connector.

(c) Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A140-9 (CSW) - I177-8 (+)

Always

Below 1 Ω

A140-9 (CSW) or I177-8 (+) - Body ground

Always

10 kΩ or higher

I177-5 (E) - Body ground

1 minute or more after disconnecting the cable from the negative (-) battery terminal

Below 1 Ω
OK

REPLACE BRAKE ACTUATOR ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR