Steering Wheel Rotation Sensor
WARNING: This page is about a different car, the 2009 Mercury Milan, 2009 Lincoln MKZ, and 2009 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
The steering wheel rotation sensor measures the rate of rotation of the steering wheel by monitoring the steering wheel rotation ring as it passes through the sensor gap. The rotation sensor uses 2 signal lines to transmit information to the ABS module about whether the steering wheel is being turned left or right and how far it is being turned. The rotation sensor does not indicate the position of the steering wheel relative to straight-ahead. The Electronic Stability Control (ESC) system learns this position by comparing the steering wheel position with other signals and storing the position it has learned. The ESC system confirms this position and modifies it as necessary during every new driving cycle.