What is an OBD2 code?

An OBD2 (On-Board Diagnostics) code is a diagnostic trouble code (DTC) generated by your vehicle's computer system when it detects a problem. These codes help identify specific issues with your vehicle's engine, transmission, emissions, or other systems.

How do I read OBD2 codes?

To read OBD2 codes, you'll need an OBD2 scanner. Plug it into your vehicle's OBD2 port (usually located under the dashboard), turn your key to the 'ON' position, and follow your scanner's instructions to retrieve the codes. Each code starts with a letter (P, B, C, or U) followed by four numbers.

What do the different types of OBD2 codes mean?

OBD2 codes are categorized by their first letter: P (Powertrain) for engine and transmission issues, B (Body) for interior systems like airbags, C (Chassis) for mechanical systems like brakes, and U (Network) for computer and module communication problems.

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Home » OBD2 Codes » P0572

Code P0572

Symptoms

• Brake lights not working

• Cruise control not functioning

• Warning light on the dashboard

Common Causes

• Faulty brake switch

• Damaged or corroded wiring

• Poor electrical connection

Glossary

PCM: Powertrain Control Module

OBD-II: On-Board Diagnostics II

Related Codes

• P0571

• P0573

Official description

Brake Switch A Circuit Low

Laymans terms

This code means that the car's computer is getting a low signal from the brake switch. It's like when a light switch in your house isn't working properly, and the lights won't turn on or off as they should.

Explanation

The P0572 code is triggered when the powertrain control module (PCM) detects a low voltage signal from the brake switch circuit.

Technical description

The brake switch is a crucial component that signals the vehicle's computer when the brake pedal is pressed. This switch is part of the brake light circuit and is also used by the PCM to control various functions such as cruise control. A low circuit signal indicates a potential issue with the switch, wiring, or connectors.

Diagnosis steps

• Check the brake lights for proper operation.

• Inspect the brake switch for damage or wear.

• Test the wiring and connectors for continuity and corrosion.

Repair procedures

• Replace the faulty brake switch.

• Repair or replace damaged wiring or connectors.

• Clear the code and test the system.

Tools required

• Multimeter

• Screwdriver set

• OBD-II scanner

Estimated repair cost

$50 - $150

Difficulty level

Moderate

Commonly affected vehicles

• Honda Accord

• Toyota Camry

• Ford Focus

Preventive measures

• Regularly inspect brake lights.

• Ensure proper maintenance of electrical systems.

• Check brake switch operation periodically.

Error code type

Sensor Issue

User experience recommendations

• Do not ignore the warning light on your dashboard.

• Have your vehicle inspected by a professional if unsure.

Warranty information

Check if your vehicle is still under warranty for coverage on electrical components.

Historical data

This code has been commonly reported in vehicles with high mileage or those frequently used in stop-and-go traffic.

Urgency level

Moderate – While the vehicle may still be operational, brake light issues can lead to safety hazards.

Legal and safety notice

Driving with non-functional brake lights can result in traffic violations and increase the risk of accidents.

Testing conditions

• Vehicle in park with engine running

• Brake pedal pressed

Component location

The brake switch is typically located near the brake pedal arm under the dashboard.

FAQs

Q: Can I drive with a P0572 code?
A: It's not recommended as it may affect brake light operation, posing a safety risk.

Q: Will fixing the brake switch clear the code?
A: Yes, replacing or repairing the faulty component should clear the code after a reset.

Last updated: Apr 16, 2026 • Source: internal database

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