VSC OFF Switch Circuit [03/2024 - ]: Procedure
WARNING: This page is about a different car, the 2025 Lexus NX 350h, 2024 Lexus NX 350h, 2023 Lexus NX 350h, and 2022 Lexus NX 350h. However, it is still accessible from the selected car via links, so may be relevant.
- READ VALUE USING GTS (TRAC/VSC OFF MODE)
- Check that the indicator light and mode condition on the GTS change according to VSC OFF switch (electric parking brake 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 Multi-information Display (Traction Control Turned Off) VSC OFF Indicator Light Not pressed Normal mode (TRC (TRAC) ON/VSC ON) Not displayed Does not come on Pressing the VSC OFF switch (electric parking brake switch assembly) TRC (TRAC) OFF mode (TRC (TRAC) OFF/VSC ON) Displayed Does not come on Pressing and holding the VSC OFF switch (electric parking brake switch assembly) VSC OFF mode (TRC (TRAC) OFF/VSC OFF) Displayed Comes on Result
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
Result:
B
INSPECT METER / GAUGE SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]
Result:
C
USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]
Result:
A
See step 2
- Check that the indicator light and mode condition on the GTS change according to VSC OFF switch (electric parking brake switch assembly) operation.
- INSPECT ELECTRIC PARKING BRAKE SWITCH ASSEMBLY
- Turn the ignition switch off.
- Inspect the VSC OFF switch (electric parking brake switch assembly).
Refer to PROCEDURE - Step 1
OK
The VSC OFF switch (electric parking brake switch assembly) is normal.
Result
Proceed to OK NG
Result:
NG
REPLACE ELECTRIC PARKING BRAKE SWITCH ASSEMBLY. Refer to REMOVAL [11/2021 - ]
Result:
OK
See step 3
- CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - ELECTRIC PARKING BRAKE SWITCH ASSEMBLY)
- Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK
The connector is securely connected.
- Disconnect the A38 No. 2 skid control ECU (brake actuator assembly) connector.
- Check both the connector case and the terminals for deformation and corrosion.
OK
No deformation or corrosion.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition A38-9 (CSW) - D161-4 (+) Always Below 1 Ω A38-9 (CSW) or D161-4 (+) - Body ground Always 10 kΩ or higher D161-7 (E) - Body ground 1 minute or more after disconnecting the cable from the negative (-) auxiliary battery terminal Below 1 Ω Result
Proceed to OK NG
Result:
OK
REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to REMOVAL [11/2021 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- Make sure that there is no looseness at the locking part and the connecting part of the connector.