What is the function of the anti-lock braking system (ABS)?
Show the correct answer
Correct answer
B. It helps to maintain the ability to manoeuvre while braking.
Explanation
In the photo, you can see an instrument cluster with a yellow ABS warning light lit, pointed out by an arrow. The anti-lock braking system allows you to keep the ability to manoeuvre the vehicle while braking - answer B.
The Road Traffic Act requires a vehicle to be built, equipped and maintained so that using it does not endanger safety - the rest is technical knowledge. ABS measures the rotational speed of the wheels, and when one of them starts to lock, it reduces and restores the pressure in its brake many times per second. The wheel keeps turning all the time, and a turning wheel keeps its sideways grip - thanks to this, you can steer and go around an obstacle without releasing the brake. Steerability is the main benefit, especially in a lorry combination, in which locked wheels on the drive axle of the tractor unit end with the combination jackknifing, and locked wheels on the semi-trailer - with the semi-trailer swinging out. Answer A describes the traction control system (ASR), which works when accelerating, not when braking. Answer C is not true: on gravel, snow or deep sand, a locked wheel pushes a ridge of material in front of it and stops in a shorter distance, so ABS may make the braking distance longer. In an emergency, you brake hard and do not ease off the pedal.
Legal basis: Art. 66 para. 1 point 1 of the Road Traffic Act (Prawo o ruchu drogowym)