P0571 Code: Cruise Control / Brake Switch A Circuit Malfunction

On-board diagnostic (OBD) codes help mechanics and vehicle owners identify possible issues in a vehicle. But before you can troubleshoot and resolve these problems, it’s important to know what these codes mean.

Code P0571 is one of many trouble codes that can be logged and retrieved from the OBD system. Here is some helpful information that can help you understand what getting this code might mean for your vehicle.

What Does the P0571 Code Mean?

Diagnostic trouble code (DTC) P0571  stands for “Brake Switch A Circuit.” It is logged when the powertrain control module (PCM) detects an issue with the brake switch or its circuit.

The brake switch is crucial to the operation of your vehicle’s cruise control system. Depressing the brake pedal is one of the ways to turn off or disable the cruise control. The brake switch tells the PCM that the brake pedal is depressed.

If the PCM detects an issue with the operation of the brake light switch, then code P0571 might be logged. This code might also be logged if the PCM detects a malfunction within the cruise control/brake switch “A” circuit.

The “A” in this code can refer to a specific wire, connector, or harness. Be sure to check out the appropriate manufacturer-specific service manual to determine what the code specifically refers to.

Depending on the severity of the problem, related error codes might also be stored with this DTC. Code P0571 is very similar to error codes P0572 and P0573.

Note: The definition of code P0571 might be different depending on the vehicle manufacturer. Consult the appropriate repair manual or repair database for the exact code definition.

What are the Common Causes of the P0571 Code?

• Defective cruise control/brake switch
• Wiring problem
• PCM issue

What are the Common Symptoms of the P0571 Code?

• Illuminated check engine light
• Cruise control will not operate
• Brake lights might not turn on
• Erratic cruise control operation

How to Diagnose the P0571 Code

Different makes and models can set the error code P0571. But this does not mean that there is a one-size-fits-all approach to diagnosing its underlying cause. The steps for troubleshooting this code will vary depending on your specific vehicle.

Check out the video below to get an idea of what the diagnostic process for this code might involve:

How to Fix the P0571 Code

Code P0571 shares similar triggers and symptoms with other engine codes. However, the appropriate diagnostic and repair procedure will depend on the specifications of your vehicle. If you’re unfamiliar with auto repair, it’s best to leave the job to a mechanic.

If you’re considering troubleshooting this code on your own, it’s a good idea to refresh your automotive knowledge before attempting any fixes. Consult a vehicle-specific repair manual or an online repair database to learn the appropriate diagnostic procedures for this code.