thanks, great advice. obviously this thing is not meant to be repaired by people like me. Anyway I took some snapshots if you care to look at it
http://www.flickr.com/photos/47324377@N03/?saved=1
thre are two electric connections going in: the upper one has two wires, the lower one three thinner wires going in. I assume the upper one is the 12 V power so I measured the voltage when pushing the window switch: it goes up from 0 to about 5-7 Volts then goes back to zero within a fraction of a second while still pushing on the switch. same thing with the other switch that controls all windows at the same time. Does it mean anything? should it not geat a steady 12 V power to move the window??
thanks a lot for your time