Anyway of finding out what the original manufacturers specs are? It would appear that some 'extras' are not visibly apparent, so if they are not working on a s/h car, unless told, one would never know.
The reason I ask is that I have two 528 E39's. A '96 and a '98. The older one certainly has a rain sensor for the wipers as the wipers do operate if the sensor position is used and it starts to rain. The other looks exactly the same, on the inside and outside area of the w/s, but either it hasn't got a rain sensor, or it's not working. Both have an auto-dim rearview mirror BTW My local BMW dealer was unhelpful when asked the same question. TIA. Mike.