Welcome to our how brake systems work page in our web site, we will provide for you free information about how the brake systems work, we will start with conventional braking systems, after that,  we will move on to ABS systems which  is a standard feature used in today's vehicles, We hope that this information will allow you to get to know your car better and feel safer while driving it.

Conventional brake systems have 11 essential items to make the system work, Brake pedal, Brake master cylinder, brake booster, brake proportioning valve, brake calipers, wheel cylinders, brake rotors, brake drums,
brake pads, brake shoes,brake hoses  and brake lines

Knowing the parts involved, we will move to the braking process.......

When you apply your foot on the brake pedal it pushes a rod connected to the brake booster ( Brake booster is the part that makes your car have power brakes, it operates with the vacuum from your engine), it is here in the brake booster that the force is multiplied, ( without a brake booster it would take a lot of effort and strength to push on the brakes, old vehicles didn't have power brakes), this force is transmitted to the brake master cylinder, it is here in the master cylinder that the mechanical movement is converted in to a hydraulic pressure



Because the brake master cylinder is the part where the brake fluid is contained, by applying force against the brake master cylinder, the valves inside the master cylinder create pressure , and this pressure is channeled through the brake lines, this pressure travels through the brake lines, the first item they encounter is the brake proportioning valve, this part is in charge of distributing the right amount of pressure to each wheel, ( without this item braking would be uneven and one or two wheels would lock up when braking), This pressure exits the brake proportioning valve, and will reach the brake calipers located in the front wheels, and the wheel cylinders located in the rear wheels, ( vehicles with four wheel disc brakes have brake calipers in the rear wheels also instead of wheel cylinders).



When the pressure is transmitted to the brake calipers, it moves a piston, or a group of pistons built in the brake calipers, this pistons force the brake pads against the brake rotors causing friction, this friction makes the car slow down by not letting the wheel move freely, in case of the rear wheels with brake drums, the hydraulic pressure pushes two pistons built in to the wheel cylinder, against the brake shoes, making them rub against the brake drums, this friction also causes the wheel to slow down by not letting it turn freely.
This is how conventional braking systems work, before ABS  braking was introduced, in our next chapter we will cover how ABS systems work





Click on image to learn how to replace the brake light switch on 1999-2005 VW Jetta.