Rain sensor fault on 530d

[steve-v8s]

I had a new windscreen fitted by the company insisted on by my insurance company and the rain sensor stopped working. Story was that it had to go to a dealer to be “Reset” . So main dealer had the car for a day but resetting failed to cure the problem, so they ordered a sensor. They had the car for another day, still not fixed so they ordered a “control box” which after another day has failed to make things work. The dealer now wants the car for two days. My gut feeling (and frankly common sense) is that the new glass is wrong not the sensor or electronics. The glass people don’t really want to know, and I suspect the dealer will start to loose interest soon. Anybody else had this problem? All advice gratefully received. In particular if anybody has a circuit diagram of the relevant part then I can have a crack at it myself. Car is a 2001 530d Sport Estate and still under warranty (just)

[juliann]

There are a number of applicable windscreens for the E39. Variants from std include Graduated Tint, Climate Comfort, Rain Sensor - or a combination of the above. If you have a non rain sensor screen fitted to a rain sensored car, the sensor will fail to work. This should be easily spotted by the dealer (or yourself as the area where the rain sensor points through the screen should look clear and uninterrupted. If you're under warranty, I would strongly recommend against pulling the unit apart as this will invalidate the warranty. If you feel the windscreen may be wrong and the repairer is not interested, tell them you will speak to your insurer (they will not want a face off with an insurance company). When I've had E39 screens replaced, they have always been replaced with genuine BMW screens which have a part no. stamped on them - if your replacement is a BMW screen check that the part no. matches with the original spec of the car.