P0571 OBD-II Trouble Code: Cruise Control/Brake Switch A Circuit Malfunction

check engine light

P0571 code definition

The P0571 code identifies a problem with the switch that deactivates the cruise control when the brake pedal is pressed.

What the P0571 code means

P0571 is the OBD-II generic code for a problem with the switch connected to the brake pedal that deactivates the cruise control system in the vehicle. If this switch is not functional, the cruise control may not operate.

What causes the P0571 code?

The brake switch code may have several causes:

What are the symptoms of the P0571 code?

The P0571 code will cause the check engine light to illuminate on the dashboard. Aside from that, symptoms may include a non-operational cruise control system. The brake pedal may not be able to deactivate the cruise control once it has been set.

How does a mechanic diagnose the P0571 code?

The P0571 code is diagnosed with an OBD-II code scanner that is capable of seeing the information coming from the engine in real-time. A qualified technician will observe when the code first appeared before clearing the code and test driving the vehicle. If the code does not immediately come back, it may just be an intermittent problem with wiring or electrical connections.

If the code does come back immediately, then further diagnosis will be necessary. The technician will use a multimeter to test the circuit for any bad signals.

Common mistakes when diagnosing the P0571 code

Since the root f the P0571 is usually an electrical problem, it is important to not overlook the little things like the fuses or the buttons on the dashboard that control the cruise control system. A problem with these components can cause the P0571 code to appear even when the brake switch is in working order.

How serious is the P0571 code?

While the P0571 code is not particularly serious all by itself, it may appear alongside other codes in the event of a serious issue with the brake pedal or cruise control. The worst-case scenario just involves the cruise control system becoming non-operational until the code goes away for good.

What repairs can fix the P0571 code?

The most common potential repairs to address the P0571 code are as follows:

  • Electrical components and connections will be inspected for signs of damage or wear.
  • Any wires or connections that do not appear to be in good working order will be repaired or replaced.
  • Once the wiring is all in good shape, the mechanic will inspect the brake pedal and brake switch.
  • If there are any parts that need replacing, the mechanic will do so before resetting the code and test driving the vehicle to see if the code returns.
  • If the code does return, the the culprit may be the controls for the cruise control system located in the vehicle.
  • The controls for the cruise control system will be inspected and anything that isn’t in working order will be repaired or replaced.

Additional comments for consideration regarding the P0571 code

Many times, the P0571 code is caused by liquids being spilled in the interior of the vehicle. The liquid can get into the controls for the cruise control and cause corrosion and/or a short circuit. In these instances, the problem is within the control for the cruise control system.

Need help with a P0571 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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