The P0571 trouble code is a diagnostic trouble code (DTC) that indicates a malfunction in the cruise control/brake switch circuit, specifically known as “Cruise Control/Brake Switch A Circuit Malfunction.” This code is logged when the powertrain control module (PCM) detects an issue with the brake switch or its circuit, which is essential for the proper functioning of both the cruise control system and the brake light operation. Understanding this code is crucial for vehicle owners and DIY mechanics who may encounter it during their automotive diagnostics.
| P0571 Code Meaning | P0571 Code Common Causes |
|---|---|
| Cruise Control/Brake Switch A Circuit Malfunction | Defective cruise control/brake switch |
| Brake switch circuit malfunction | Wiring issues (e.g., pinched or chafed wires) |
| Issues with brake light operation | Faulty engine control module (ECM) |
| Erratic cruise control functionality | Debris or dirt affecting switch operation |
| Inoperative cruise control system | Improper adjustment of the brake switch |
Symptoms of P0571 Code
The symptoms associated with the P0571 code can vary, but common indicators include:
- Illuminated Check Engine Light: The most noticeable symptom is the illumination of the check engine light on the dashboard.
- Non-Operational Cruise Control: The cruise control system may not engage or function properly.
- Brake Lights Not Illuminating: If the brake switch is defective, the brake lights may not activate when the pedal is pressed.
- Erratic Cruise Control Operation: Functions such as setting, resuming, or accelerating may not work consistently.
These symptoms can lead to safety concerns, particularly if the brake lights do not function correctly, potentially causing accidents.
Technical Explanations
The P0571 code indicates that there is an issue within the circuit that connects the brake switch to the PCM. The brake switch plays a critical role in deactivating the cruise control when the brake pedal is pressed. If this switch fails or if there are wiring issues, it can result in a malfunctioning cruise control system and improper brake light operation.
How the System Works
When you press the brake pedal, the brake switch sends a signal to the PCM to deactivate the cruise control. If there’s a fault in this circuit—such as a broken wire, a defective switch, or an issue with the PCM itself—the P0571 code will be triggered. Understanding how these components interact is essential for diagnosing and repairing this issue effectively.
Step-by-Step Diagnosis
Diagnosing a P0571 code involves several steps:
- Scan for Codes: Use an OBD-II scanner to confirm that P0571 is present and check for any related codes that might provide additional context.
- Visual Inspection: Inspect the wiring and connectors associated with the brake switch for any visible damage, corrosion, or loose connections.
- Test Brake Switch Operation: Using a multimeter, test the continuity of the brake switch. Ensure it operates correctly when pressed and released.
- Check Power and Ground: Verify that power is reaching the brake switch and that it has a good ground connection.
- Examine Cruise Control System: If all else checks out, investigate other components related to the cruise control system, such as switches on the steering wheel or any associated fuses.
Solution Methods
Once diagnosed, here are common solutions for addressing a P0571 code:
- Replace Defective Brake Switch: If testing reveals that the brake switch is faulty, replacing it will usually resolve the issue.
- Repair Wiring Issues: If damaged wiring or connectors are found during inspection, repair or replace them as necessary.
- Check and Replace Fuses: Ensure that all relevant fuses are intact and functioning properly; replace any blown fuses.
- Inspect Cruise Control Components: If problems persist after addressing the brake switch and wiring, further inspection of other cruise control components may be needed.
Cost Estimates
The cost of repairs can vary widely based on labor rates and parts costs in your area:
- Brake Switch Replacement: Typically ranges from $50 to $150 for parts and labor.
- Wiring Repairs: Depending on complexity, costs can range from $100 to $300.
- Diagnostic Fees: Expect to pay between $75 to $150 for a professional diagnostic service if you choose not to perform this yourself.
Warnings and Recommendations
- Professional Help Advised: If you are not confident in your ability to diagnose or repair electrical issues, it’s best to seek professional assistance.
- Safety First: Always ensure your vehicle’s braking system is functioning correctly before operating it. Ignoring problems with your brakes can lead to serious safety hazards.
- Regular Maintenance: Regularly inspect your vehicle’s electrical systems as part of routine maintenance to prevent issues like those indicated by P0571 from occurring in the first place.
Closing Paragraph
The P0571 trouble code indicates a malfunction in your vehicle’s cruise control/brake switch circuit, which can lead to significant operational issues if left unaddressed. By understanding its symptoms, causes, and repair methods outlined in this guide, vehicle owners and DIY mechanics can effectively diagnose and resolve this issue. Always prioritize safety by ensuring proper function of your braking system and seeking professional help when needed.
Frequently Asked Questions About P0571
- What does error code P0571 mean?
P0571 indicates a malfunction in the cruise control/brake switch A circuit. - What are common symptoms of P0571?
Symptoms include an illuminated check engine light, non-operational cruise control, and malfunctioning brake lights. - Can I drive my car with a P0571 code?
While it’s generally safe to drive short distances, it’s advisable to address this issue promptly due to potential safety risks. - How do I fix error code P0571?
Fixes typically involve replacing a faulty brake switch or repairing damaged wiring. - Is P0571 serious?
P0571 itself is not critical but may indicate underlying issues that could affect vehicle safety. - How much does it cost to fix P0571?
The cost can range from $50 for parts alone to several hundred dollars depending on labor and additional repairs needed. - Can I reset P0571 myself?
You can clear codes using an OBD-II scanner; however, addressing underlying issues is essential for long-term resolution. - Should I consult a mechanic for P0571?
If you’re unsure about diagnosing or repairing electrical systems, professional help is recommended.