Normal Operation
WARNING: This page is about a different car, the 2005 Mercury Mountaineer and 2005 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
The wheel speed sensor and sensor ring generate a signal to the anti-lock brake system (ABS) module that is proportional to the wheel speed. The ABS module compares the wheel speed inputs from all wheel speed sensors to determine an impending wheel lockup.