What Is a Brake Light Switch?

Cars rely on a number of systems in order to run properly. The breaking system in a car consists of both mechanical and electrical parts used to complete the standard breaking procedure. The brake light switch plays an integral role in this process.

Definition

  • A brake light switch is an electrically powered switch that triggers the brake lights to activate when brakes are applied.

Process

  • A brake light switch operates via two wires, called a power-in wire and power-out wire. When a driver depresses the brake pedal, a plunger device contacts a metal plate, which completes an electric circuit in the switch via the two wires. The switch then activates the brake lights.

Applications

  • Brake light switches can be used for such applications as cruise control cut off and shift lock trigger. Brake light switches used for cruise control work by transmitting a signal to the car’s computer unit, which then cuts the cruise control to enable deceleration. The brake light switch also sends a signal to the computer when activating shift lock or automatic transmission. Shift lock assures the brake pedal is depressed before allowing the car to shift gears.