Question

what component allows the wheel speed sensors to monitor wheel speed?
a) rotor
b) tone ring
c) abs control module
d) hcu

Explanation:

• Rotor: In the context of wheel - speed monitoring, a rotor is not the component that directly allows wheel - speed sensors to monitor speed. Rotors are mainly associated with braking systems (e.g., brake rotors) and do not have a direct role in sensor - based speed monitoring.
• Tone ring: A tone ring (also known as a reluctor ring) is a crucial component. As the wheel rotates, the tone ring rotates with it. The wheel - speed sensor (which can be a magnetic or Hall - effect sensor) detects the changes in the magnetic field (in the case of magnetic sensors) or the position (in the case of Hall - effect sensors) caused by the teeth or notches on the tone ring. This change is then translated into an electrical signal that represents the wheel speed.
• ABS control module: The ABS (Anti - lock Braking System) control module is responsible for receiving the signals from the wheel - speed sensors, processing them (e.g., calculating wheel speeds, detecting wheel lock - up conditions), and then sending control signals to other components (like the hydraulic control unit). It does not directly allow the sensors to monitor speed; it just processes the sensor - generated signals.
• HCU (Hydraulic Control Unit): The HCU is part of the ABS system. It is responsible for controlling the hydraulic pressure in the braking system based on the signals from the ABS control module. It has no direct role in enabling the wheel - speed sensors to monitor speed.

Answer:

B. Tone ring