What is the solution for the P0571 trouble code?
3 Answers
P0571 trouble code causes include the brake light switch, its circuit, or connectors. After troubleshooting the vehicle, it is generally necessary to clear the trouble code. When clearing the code, strictly follow the specified method for the particular vehicle model. Here is more information about the P0571 trouble code: 1. Introduction: Trouble code P0571 refers to the brake switch A circuit. The brake switch transmits information about whether the brake pedal is pressed to the Electronic Control Unit (ECU) in the form of an electrical signal, serving as a crucial basis for stopping cruise control and disengaging the torque converter. The ECU does not detect changes in the brake switch signal during the self-test when the key is turned on and the engine is running. 2. Precautions: When clearing the code, strictly follow the specified method for the particular vehicle model. Do not simply disconnect the negative battery terminal to clear the trouble code. Otherwise, it may lead to the following issues: First, it may cause the control computer of certain vehicle models to lose "experience memory." If the negative battery terminal is disconnected, the engine operation data stored in the Random Access Memory (RAM) will be automatically cleared, resulting in poor vehicle performance for a considerable period after repair, or the reappearance of previous trouble codes shortly after driving. Additionally, it may cause the loss of certain functions, such as the audio lock, which is a common issue. In such cases, a complicated repair procedure is required to decrypt the audio system to restore its original functionality.
A while ago, my car also showed the P0571 trouble code, which was quite annoying. I know this code usually indicates an issue with the brake switch circuit for cruise control. That day, the cruise control failed while driving, so I immediately took it to the shop for inspection. The mechanic first checked if the brake light switch was faulty—since an incorrect signal from this switch can trigger this code. If the brake lights weren't working either, it was likely a faulty switch needing replacement. Next, they tested the entire circuit for shorts or open circuits, used a multimeter to measure resistance, and found some aging wires, so they rewired them. The mechanic also confirmed the fuse wasn’t blown. The whole process took about an hour, and after replacing the switch, the code cleared. I suggest you visit a professional shop as soon as possible—don’t delay, as cruise control failure on the highway can be dangerous. Regular maintenance can help prevent this, such as periodically checking the wiring and switches.
I've encountered the P0571 trouble code multiple times, which is primarily related to the sensor switch in the cruise control system. Simply put, this code appears when there's an error in the brake signal while cruise control is active. You should start with the brake lights—if they illuminate normally, the issue might be a faulty switch or loose wiring; if they don't light up, just replace the switch. I usually begin by using a diagnostic tool to read real-time data, checking if the switch signal fluctuates. If abnormalities are detected, I proceed to disassemble and inspect. Don't forget the fuse box—sometimes a blown fuse can trigger this code as well. Take your time with the process: clean the contacts, test the cables. If you don't have the tools, it's best to take it to a repair shop where they can quickly pinpoint the issue with their experience. This code isn't a major problem, but it needs timely attention to avoid compromising driving safety. I often advise friends not to ignore small warning lights.
