Mercedes C350 cabriolet tot won't go up but half way and stalls why

Taken for the interwebs: did you recently have a dead battery? Either way try to resynchronize your windows (i'm not sure if you meant front window or rear quarter window). If you hold the window switch in the up position(car running and door closed) untill window reaches the top and continue to hold for 10 seconds the window will reprogram itself. try both front windows. This system is complicated and is best diagnosed via s.d.s. diagnostic machine. I will give you a couple of other possible easy remedies. If your vehicle is equiped with a ski window in the rear trunk panal the door must be shut, also your cargo cover must be shut and plastic lid secured. There are numerous micro switches that input to your soft top control unit-any one could cause the top to be inop. Check to make sure the switch on the cargo cover( retractable cover in trunk) is secured to it's housing, they do periodically fall off. Also if your roll bar ( rear head rests ) has been mechanically deployed You must hold the switch in the up position untill the rams lock back into the roll bar-does the roll bar operate? Always operate top with vehicle running because they are very voltage dependent. Your owners manual will explain how to manually raise top and some simple operation and repair remedies. If you are knowledgable about automotive electrical systems you can disconnect both leads from the battery and touch them together to drain the capacitors and it may reset the module( do not attempt if you are not knowledgable with automotive electricity because there are many things that can go wrong. hopefully I have been helpful.

I assume you mean a CLK350. This may also help: http://mbworld.org/forums/clk-class-w209/349874-convertible-top-won-t-go-down.html