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 active wheel speed sensor generates a signal that is sent to the anti-lock brake system (ABS) module. The wheel speed sensor circuitry connects to the ABS module connector C155 through 2 wires and a connector at each wheel speed sensor. When the ignition switch is turned to the RUN position, the ABS module carries out a self-test by sending a reference voltage through the right front wheel speed sensor and its circuitry to determine if they are functional.
Voltage is supplied to the active wheel speed sensors from the ABS module. The wheel speed sensor ground is supplied by the ABS module.