Hi to all

Just purchased 1994 C280 and i am well pleased
This is my first MB so i would be greatful for any help and info. A couple of questions 1) The central locking pump appears to run for anything upto 5 mins as soon as the ignition is switched on, it doesn't run continuous but appears to run on for 3seconds then off for 1second continually wether you actually start the engine or not, is this normal? 2) front passenger electric window packed up. drivers side ok. Its not the switch, I,ve checked it. but I am unable to get any further because of the lack of diagrams. Does anybody know where i can get good service manuals for this model? I presume the windows work from a relay? but i cant find one for them (so maybe they dont?).So do I strip the door and go for the motor? Any help would be very welcome

cheers