Mercedes will be outfitting S-Class vehicles with flashing brake lights in Europe but not in the U.S. The new technology, designed to make the difference between a panic stop and normal braking apparent, will flash the lights if the brakes were applied suddenly. Mercedes hopes the flashing lights on the car ahead would cause drivers to apply the brakes more quickly to avoid a crash. U.S. regulators will not change a federal rule that requires steady illumination of brake lights, though the European Union will allow the flashing lights. The NHTSA is looking into other answers to this problem including brighter brake lights that would illuminate if a panic stop were detected.