Originally Posted by Weasel

In my personal experiances and observations with E53's, faults for wheel speed sensors go like this...

Either front sensor, usually just the sensor.
Right rear sensor fault usually the DSC module.
Left rear sensor faults usually the Instrument cluster.

As for diagnosis, I think you are looking too deep, these measure fron the side of the tip from the back of the wheel bearing, and the micropulses are harder to read even without a graphing ocilloscope due to the size and frequency. Just simply read which side the sensor fault is on, swap the sensors left/right for either respective axle, clear faults then drive. If the fault followes the sensor, replace the sensor. If it stays in the same position, check the wires between the sensor plug and the DSC module if needed before buying the components mentioned above.

That is the good thing about both sensors being the same for each axle, just swap them for diagnosis.

This is the methods I used when diagnosing my own truck (which needed a DSC module, r/r sensor fault) and my mothers E39. (which just needed a front sensor)