I have rear window problems on 1996 C180.
once left wondow stall, did not down.
we opened motor and did not find any problem, then we put motor back, then when we tried and wondow worked.
It heppend 3time. when windows stalled, we disassembled and assemble motor, then window worked.
Someone sad that in motor is a little thermal control-which is cousing the problem. I got this and If you need I can upload pictures.
What can you advice.