Couple weeks ago took the car for a wash (those where you drive in) and panicked a little bit when was already inside the damm thing, sensors beeping like crazy and I forgot to press the button where you can turn them off (stupid me, put my hands on my ears as it was so noisy inside!!!!

Im now getting a PDF failure warning and sensors don't work, although there are times where it works just fine (all sensors). I think there is probably on acting up and since they are all inter-connected (thats what I read) the "Bad one" is basically disabling the whole system. Cameras all work fine, and as I said, there are times where all sensors work and no warning!
Anyone have had this happened before or should i just take to BMW to take a look? What costs should I expect to get it sorted? By the way I have extended warranty, not sure if this is covered under it?
Thanks again