Dear All Please how does a brake switch work?

When the brake pedal is in its resting position, its upper structure (near the pivot) pushes a plunger on the brake light switch that opens the brake switch contacts making the brake lights go off. The switch should be adjusted in this position, making sure the brake lights are off, when the brake pedal is not being pressed.

Then when the brake pedal is pressed, it moves away from the brake switch, making the contacts close, making the brake lights go on.

SOME vehicles use a relay to power the brake lights, and in those vehicles, the brake light switch activates the relay which takes all the brake light current.

This type of momentary action, spring-loaded switch has "normally closed" (n.c.) contacts. If you hold the switch in your hand (not installed in the car), the contacts are closed, meaning the switch is ON.

-General automotive mechanic since 1972

The most simple design is a plunger design. When you press the pedal, the plunger is pushed in and that activates the brake lights. Think of it as a light switch...it's either on or off.

They are mounted on a bracket near the driver's side of the brake pedal lever. When the brake is pushed the lever releases the push button brake switch and the switch makes contact. When the brake is released the lever pushes the switch again and breaks contact. In manual transmission vehicles there is often a second switch on the bracket for the starter safety interlock.

Pull it down it goes off
Push it up it goes on

"Dear"? You don't even know any of us! Learn to use your search box and type that question there!

Hi so it applies a brake electronically using a solenoid.