Emergency brake lights are activated at speeds above 50 km/h(31 mph) in the event of heavy braking. After the car's speed has been slowed down to below 10 km/h(6 mph) the brake light returns from flashing to the normal constant glow - while at the same time the car's hazard warning lights are activated. These flash until the driver accelerates the car to a higher speed again or switches off the hazard warning lights.
Foot brake - emergency brake lights and automatic hazard warning flashersUpdated 7/23/2018
Emergency brake lights are activated to alert vehicles behind about heavy braking. The function means that the brake light flashes instead of - as in normal braking - shining with a constant glow.