Some vehicles are equipped with brake pads wear level warning system to ensure the brake pads are in good working order. The system usually triggers a light on the dash to notify car owners that replacing the worn brake pads and inspect/replace other parts of the brake system are needed soon. This warning system relies on a brake pads wear sensor to be effective. This sensor should be replaced when replacing brake pads. Our brake pads wear sensors are built to exact specifications required by the car manufacturers. Please inquire with your dealers to find out if brake sensors are needed for your vehicle.