What Happens When You Hit the Brake Pedal – Explained Here!

Welcome back to my short series on automotive how to guides for the new weekend warrior auto mechanic. This isn’t meant for the pro auto mechanic, but instead it’s for the average Joe who is looking to get his hands a little greasy on the weekends. In previous articles, we had covered a lot of tools but in today’s article I’m going to cover what occurs when you put your foot on the brake pedal of your car. The brakes are probably the most important and yet overlooked safety item that your car could have. Without a proper understanding of what happens inside your braking system, it can be difficult to troubleshoot any problems that may arise. So here we go, here’s what happens when you hit the pedal.

-When you push on your brake pedal, it pushes on another piston in a cylinder known as the brake master cylinder. You can typically find it right in front of the driver’s side of the engine compartment against the firewall.

-When the master cylinder is pressurized, it forces brake fluid into a distribution block depending on your car braking system. From there, the fluid is forced down a set of hard lines, one for each wheel.

-Each wheel will either have a drum or a disc brake. They serve the same purpose but operate slightly differently. For simplicities sake, I’ll describe the disc brake that’s most commonly found on vehicle’s today. The brake fluid from the hard line will force the brake caliper to squeeze a set of pads against what’s known as the disc or rotor. This pressure slows the rate at which the tires spin and therefore slow down the car.

-When you release pressure from the brake pedal, the whole situation reverses and fluid is drawn back up into the brake master cylinder through the hard lines.

And there you have it. Now you know what all occurs when you step on your brake pedal.