DTC P0571-62: Brake Switch "A" Signal Compare Failure [10/2022 - ]: Description

WARNING: This page is about a different car, the 2025 Lexus RX 350, 2024 Lexus RX 350, and 2023 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.

This DTC is stored when the brake signal sent via direct line and the brake signal sent via CAN communication do not match.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	DTC Output from	Priority	Note
P0571-62	Brake Switch "A" Signal Compare Failure	The brake signal sent via direct line and the brake signal sent via CAN communication do not match. (1-trip detection logic*)	Electronically controlled brake system Stop light switch assembly Certification ECU (smart key ECU assembly) Wire harness or connector	Power Source Control	A	DTC Output Confirmation Operation: Connect the cable to the negative (-) auxiliary battery terminal, release the brake pedal and wait at least 20 seconds. Then depress the brake pedal for 20 seconds or more.

*: Only detected while a malfunction is present and the ignition switch is ON.

VEHICLE CONDITION AND FAIL-SAFE FUNCTION WHEN MALFUNCTION DETECTED

Vehicle Condition when Malfunction Detected	Fail-safe Function when Malfunction Detected
If there is a malfunction when the brake signal sent via direct line is on, the engine can be started by pressing the engine switch with the brake pedal released. If there is a malfunction when the brake signal sent via direct line is off, the engine cannot be started by pressing the engine switch with the brake pedal depressed. With the electrical key transmitter sub-assembly in the cabin, even if an engine start operation is performed, the engine does not start (the key indicator display is not displayed on the multi-information display). However, the engine can be started by turning the ignition switch to ACC and then pressing and holding it.	-

Vehicle Condition when Malfunction Detected

Fail-safe Function when Malfunction Detected

If there is a malfunction when the brake signal sent via direct line is on, the engine can be started by pressing the engine switch with the brake pedal released.
If there is a malfunction when the brake signal sent via direct line is off, the engine cannot be started by pressing the engine switch with the brake pedal depressed.
- With the electrical key transmitter sub-assembly in the cabin, even if an engine start operation is performed, the engine does not start (the key indicator display is not displayed on the multi-information display). However, the engine can be started by turning the ignition switch to ACC and then pressing and holding it.

RELATED DATA LIST AND ACTIVE TEST ITEMS

DTC No.	Data List and Active Test
P0571-62	Power Source Control Stop Light Switch