The primary function of the brake light switch is to activate the brake lights when the brake pedal is pressed. When you apply pressure to the brake pedal, the switch is triggered, completing an electrical circuit and causing the brake lights to illuminate. In many modern vehicles, the brake light switch is also integrated into the shift interlock system. This means that the switch must be engaged (brake pedal pressed) to allow the driver to shift out of "Park" and into another gear, such as "Drive" or "Reverse." This interlock system prevents accidental shifting when the brake pedal is not depressed.
In some vehicles equipped with cruise control, the brake light switch is used to deactivate the cruise control system when the brakes are applied. This safety feature ensures that the vehicle slows down when the driver applies the brakes while using cruise control.
Brake lights do not light up when the brake pedal is pressed, risking safety.
Difficulty shifting out of "park" even with the brake pedal pressed.
Cruise control may not disengage when brakes are applied.
Activation of abs or traction control warning lights on the dashboard.
A stuck switch can drain the vehicle's battery due to continuous brake light illumination.
In automatic vehicles, it can hinder gear shift release from "park".
Brake lights may work inconsistently.
Check for physical damage or wear on the switch or electrical connections.