Located at the lower part of the steering column, steering angle sensor incorporates a microprocessor, and is connected to the DSC control module through PT-CAN bus. To measure the steering angle and rate of steering, this sensor employs two potentiometers The microprocessor uses the raw signals provided by these potentiometers to develop the steering angle signal which is supplied to the PT-CAN bus. The DSC control module has its own logic that assesses the likelihood of the steering angle sensor signal based on other signals, for instance wheel speeds and/ or acceleration inputs. When the voltage of battery is interrupted, the DSC control module estimates the amount of steering wheel rotation through the wheel speeds. When the steering or suspension has been worked on, one has to replug the sensor, and when the steering angle sensor has been changed, it needs to be coded. Both service procedures require the use of the BMW diagnostic scan tool and if replacing the sensor should be re-coded before setting it up.