So, my wife and I play a lot of games on the PC where we both use Xbox 360 controllers. One is brand name, the other is a well-reviewed generic. Recently, the generic one broke in a very specific way - most of the down/left diagonal zone on the left thumbstick doesn't work. I disassembled it and re-soldered the leads on the stick, but that didn't help. In retrospect, no real reason it should - both directions work
, just not when input together. Anyway, I don't know how to repair it or what to search for - "dead zone" brings up a bunch of fps games and most people have problems with drift, not a specific dead area, and the dead areas that are common are usually left or right or up or down, since the whole thing is just two dimensions of potentiometers. My questions are thus: what is going on, exactly, and how do I fix it? I mostly care about the fix, but I've also been learning some electrical engineering and it bothers me that I'm not sure what is going wrong.
Oh, tiny bit of extra information: It's not a 90 degree sector that's dead, probably ~45 or 50 degree one. And only at the very edge - it seems like it works if it's not being pushed all the way. It's weird!