Winter Terapy

I've had the same problem, here is the solution, in another thread:

After two weeks of usage, my servo started jamming at one side, and not going back to center. Long story short, I found the solution. The root of a problem is a small gaps between contact pads. I've marked them yellow on the attached picture. After intensive rotation copper smeared between two pads, and they become short circuited. Solution is very simple - clean the gap with knife or so. Of course if I was able to send my servo to LEGO I'd rather do that.