Is it correct not to release the brake pedal when ABS is active?
2 Answers
It is correct not to release the brake pedal when ABS is active; instead, you should firmly press the brake pedal. The Anti-lock Braking System, abbreviated as ABS, functions by automatically controlling the braking force during vehicle braking to prevent wheel lock-up, keeping 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. Here is an introduction to the ABS system: 1. Working Principle: During braking, ABS quickly determines the lock-up state of each wheel based on speed signals from wheel speed sensors. It closes the normally open input solenoid valve for the wheel that begins to lock, maintaining the braking force. If the wheel continues to lock, the normally closed output solenoid valve is opened, causing the braking pressure on that wheel to drop rapidly due to the direct connection to the brake fluid reservoir, preventing the wheel from fully locking due to excessive braking force. This keeps the braking state at the optimal point (slip ratio of 20%), achieving the best braking effect and ensuring driving safety. 2. Limitations: The ABS system itself has limitations and cannot completely overcome certain physical laws. In two scenarios, ABS cannot provide the shortest braking distance. One is on smooth dry roads when braking is performed by an experienced driver. The other is when braking on loose gravel, loose soil, or deep snow-covered roads. Additionally, on dry roads, the latest ABS systems can control the slip ratio within a range of 5% to 20%, but not all ABS systems operate at the same rate or to the same degree during braking. Although a four-wheel anti-lock braking system can enable the vehicle to brake within the shortest possible distance, if braking is initiated too late and the vehicle cannot come to a complete stop before colliding with an obstacle, the system cannot prevent the accident.
I've been driving for over a decade and have experienced ABS activation several times. Like that time on the highway during a heavy rainstorm when traffic suddenly came to a halt ahead. I slammed on the brakes and felt the pedal vibrate like it was dancing. I was a bit scared and wanted to lift my foot to see what was happening, but immediately remembered what my driving instructor taught me: keeping your foot firmly on the brake pedal when ABS is working is absolutely correct. That's because when the ABS system detects that a wheel is about to lock up, it rapidly adjusts brake pressure to prevent tire skidding, allowing you to maintain steering control. If you lift your foot at this moment, the system gets interrupted, braking force suddenly decreases, and the car might skid or fail to stop properly. I have a friend who lifted his foot in such a situation, resulting in loss of vehicle control and a collision with guardrails, costing over ten thousand in repairs. My advice to new drivers: find an open area to practice emergency braking, get used to maintaining steady pressure, and become accustomed to that vibration - it's nothing to worry about. ABS is designed to protect you, so trust it.
