Why is there a clicking sound when braking on snowy days?

[DeCody]

When there is a clicking sound while braking on snowy days, it indicates that the ABS (Anti-lock Braking System) is activated. The ABS, short for Anti-lock Braking System, functions by automatically controlling the braking force of the brakes during vehicle deceleration to prevent the wheels from locking up. This keeps the wheels in a state of rolling and sliding (with a slip ratio of around 20%), ensuring maximum adhesion between the wheels and the road surface. When the ABS is in operation, it essentially performs rapid, high-frequency pumping of the brakes. During ABS activation, the friction between the wheels and the road surface is rolling friction, which maximizes the adhesion between the wheels and the road for braking, enhances deceleration efficiency, and shortens the braking distance. Most importantly, it ensures the directional stability of the vehicle.