DTC P0571-13: Brake Switch "A" Circuit Open [11/2021 - ]: Procedure
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2025 Lexus NX 350, 2025 Lexus NX 250, 2024 Lexus NX 350, 2024 Lexus NX 250, and 2023 Lexus NX 350. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY OUTPUT CIRCUIT)
- Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK
The connector is securely connected.
*a Component with harness connected
(Stop Light Switch Assembly) - Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition A37-2 (L) - Body ground Brake pedal depressed 11 to 14 V A37-2 (L) - Body ground Brake pedal released Below 1.5 V Result
Proceed to OK NG
Result:
NG
REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to REMOVAL [11/2021 - ]
Result:
OK
See step 2
- Make sure that there is no looseness at the locking part and the connecting part of the connector.
- CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY INPUT CIRCUIT)
Procedure1
- Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK
The connector is securely connected.
Pre-procedure1
- Disconnect the A36 skid control ECU (brake actuator assembly) connector.
Procedure2
- Check both the connector case and the terminals for deformation and corrosion.
OK
No deformation or corrosion.
Procedure3
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition A36-4 (STP) - Body ground Brake pedal depressed 11 to 14 V Result
Proceed to OK NG Post-procedure1
- None
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.