What role does a speed sensor play in an anti-lock braking system?

The speed sensor is a vital component of an anti-lock braking system (ABS) because it measures the rotational speed of each wheel. This data is crucial for the ABS to function effectively. When the system detects a difference in wheel speed, which could indicate that a wheel is about to lock up during braking, it can intervene by modulating brake pressure to prevent skidding and maintain steering control.

The ability to accurately measure wheel speed allows the ABS to optimize braking performance, ensuring safer vehicle operation during sudden stops or adverse conditions. In contrast to the other options, which involve different vehicle systems or functions, the speed sensor's primary and critical role is focused solely on monitoring the speed of the wheels to enhance braking safety and effectiveness.