Circuit/System Description
WARNING: This page is about a different car, the 2011 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.
The wheel speeds are detected by passive wheel speed sensors. Each wheel speed sensor receives a 5 V reference signal from the electronic brake control module (EBCM) and provides an alternating current (AC) square wave signal to the EBCM. As the wheel spins, the wheel speed sensor produces an AC signal. The EBCM uses this AC signal to calculate wheel speed. The wheel speed sensors are replaceable only as part of the wheel hub and bearing assemblies.