This is a known problem. With the retrofit kit wiring loom and (evidently some factory fit wiring looms, there was a fault with one of the pins into the nav computer.

See http://www.xoutpost.com/articles/all-...formation.html

Which may explain.....

I had this fault on my E46 Nav and it took AGES to get resolved. Only after I printed stuff out from here and a couple of other forums and the BMW tech raising a PUMA case, was the issue confirmed. Moving the pin across remedied the wheel sensor issue, and improved the nav accuracy greatly