Andries, thanks nice pics and instruction. Quick silly question, where is the positioning sensor located? is it somewhere around the vacuum unit or is emptying the unit necessary because of built up pressure. Haven't really worked on the 850 like my other car cause, one, it was under warantee till a year or so ago and two, it hasn't really given me any problems till now. Also, do you know roughly what the cost of this part is, i am alittle mechanically inclined but not sure how easy this thing is to fit? you mentioned you soldered a wire to the unit to ensure a good connection, where did you get the wire again? any additional info would be much appreciated. thanks Ken