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The anti-lock brake system (ABS) is a safety component that aids steering during hard braking by restoring tire traction.



What are ABS Brakes?

Also referred to as an anti-skid braking system, this feature increases vehicle safety by preventing wheels from locking up, helping to keep your car’s tires from skidding during an emergency. ABS also shortens braking distance and enhances vehicle control by regulating individual wheel brake pressure with much greater precision than conventional braking.

How do ABS Brakes Work?

ABS uses a combination of your vehicle’s electronic control unit, speed sensors, valves, pump, and brake hydraulic modulator. The controlling components monitor your vehicle’s speed sensors, inspecting for any deaccelerations that may occur while reducing and increasing pressure to the brake during these episodes. Speed sensors at the wheels detect and report changes in wheel speed during braking. The speed sensor sends a signal to your engine control unit (ECU), which receives and processes the speed sensor(s) signal. Individual wheel lockup during braking is minimized, thus the “anti-lock” function.

How are ABS Brakes Made?

ABS brakes are composed of four main components – controller, valves, speed sensors, and pumps. These components are integrated into the brake hydraulics. There is also a failsafe to ensure normal braking hydraulics should the ABS fail. ABS is essentially a precision computer map tailored to the specific application.

Why do ABS Brakes Fail?

  • Contaminated brake fluid causes restriction and internal corrosion
  • Wheel speed sensor failure
  • Motors fail

What are the Symptoms of ABS Brake Failure?

  • ABS warning light appears
  • System will rely back on manual braking methods

What are Consequences of ABS Brakes Failure?

  • Integral units will need to be fully replaced
  • Increased braking distance and reduced vehicle stability under braking

If you have questions or concerns about your anti-lock braking system, or any of your vehicle’s components, come into your local Pep Boys where we can answer any question, help you find any part, or perform any vehicle service you might need. If you want to learn more about other car parts, especially as they apply to anti-lock brake systems, we recommend reading up on brake rotors, brake lines and steering gear boxes