Brakes

All drivers know that to stop a vehicle, you press the brake pedal. But how does the pedal make the vehicle stop?

Brake systems slow and stop the vehicle by applying pressure to rotating brake discs and/or brake drums, which are attached to each wheel. Think of brakes on a bicycle—when you squeeze the lever, a cable pulls the rubber blocks and squeezes them together, which applies pressure to the rim of the wheel, causing it to slow or stop. This is very similar to how disc brakes work on a vehicle. The brake caliper squeezes the brake pads against the brake discs until they slow or stop.

Some vehicles employ drum brakes on the rear wheels, which utilize brake shoes instead of brake pads. The shoes are located inside the brake drum and push outward in order to slow or stop the wheel. Most modern vehicles also use a brake booster, which helps reduce the force the driver must exert against the brake pedal in order for the brakes to work.

You may have also heard of anti-lock brakes. The purpose of an anti-lock brake system (ABS) is to prevent the wheels from locking up or skidding during hard braking. If the brakes lock up, the vehicle takes longer to stop and the driver will have a difficult time steering and maintaining control of the vehicle.

The ABS system prevents wheel lock-up by monitoring each wheel with a wheel speed sensor. When the wheel starts to lose traction, the wheel speed sensor sends a message to the ABS control module, which will temporarily reduce hydraulic pressure to the wheel to prevent it from skidding.

How to Fix Your Brakes
Video, Step-by-Step Instructions, Parts & Tools List