Torque Sensor
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The power steering control module (PSCM) uses a combination of the torque sensor, motor rotational sensor, vehicle speed, and calculated system temperature inputs to determine the amount of assist needed. As the steering wheel is turned and torsional twist is applied to the steering shaft, the torque sensors input and output shaft sinusoidal voltage signals are processed by the PSCM to detect and calculate the steering torque. Additionally, the difference between the angle of the steering output and input shafts detected by the torque sensor and the sinusoidal voltage signals of the motor rotational sensor are both processed by the PSCM to detect and calculate the steering wheel angle.