Circuit/System Description
WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
The power steering control module (PSCM) continuously monitors the position sensor sine wave frequency signals. The sine wave voltage signals of the position sensor and the angle difference between the steering column output and input shafts detected by the torque sensor are both processed by the PSCM to detect and calculate the steering wheel angle.