What Causes the Abnormal Noise When Braking on Snow?
2 Answers
When braking on snow, the abnormal noise is caused by the intervention of ABS. In winter, roads are covered with ice and snow, significantly reducing the friction between the ground and tires, leading to wheel lock-up during braking. When the vehicle detects wheel lock-up, the ABS system intervenes in the braking action to maximize the vehicle's braking capability. The abnormal noise occurs when ABS is engaged. ABS is primarily classified by channels. In ABS systems, the brake lines capable of independently adjusting brake pressure are referred to as control channels. ABS devices are categorized into four-channel, three-channel, two-channel, and one-channel types. One-channel ABS: Also known as single-channel ABS, it features a single brake pressure regulator in the rear wheel brake line and a wheel speed sensor installed on the rear axle differential (sometimes one on each rear wheel). Two-channel ABS: This type of ABS struggles to balance directional stability, steering control, and braking efficiency, making it rarely used today. Three-channel ABS: It independently controls the two front wheels while jointly controlling the two rear wheels based on the low-select principle (i.e., both wheels are controlled by one channel to ensure the wheel with less traction does not lock up), also known as hybrid control. Four-channel ABS: Equipped with four wheel speed sensors, it includes a brake pressure regulator in each of the four wheel brake lines for independent control, forming a four-channel control system.
I remember the first time I drove in the snow last winter, I was startled by a strange clicking sound when I hit the brakes. Later, I asked a friend and learned that this kind of unusual noise is usually caused by snowflakes or ice getting stuck between the brake disc and brake pads, creating friction noise when braking. Also, the ABS system is particularly active on snowy roads because it prevents tire skidding, and it makes a regular clicking sound when working. In cold weather, metal parts are more prone to contraction and deformation, which can exacerbate the noise. It's recommended to check if there's any snow or ice buildup in the brake system, maintain proper tire pressure, and if the noise persists, visit a professional repair shop. Safety comes first when driving in the snow.
