Very gently and no alcohol. A cloth and a tactical eraser - an eraser small enough to get in-between the traces. The traces are easily eroded. Then poof! That's that..
From the looks of it the left sheet at the 10 o'clock position looks totally worn away. Depending what's left it may still work. If you do clean them, I suggest practicing on some junk or something first.
Sometimes they can be drawn back in - I've had good luck with a conductive pen. And it took patience. And it was for a keyboard mylar sheet. Heh. First time I tried soldering them - whooops!
Those are so incredibly cheap to make there's no convincing companies NOT to use them. It also speaks to the specified design life of 3 years for that console.
Your best bet is to find some controllers and cannibalize new flex circuits. that's what they're called.
Anyone ever notice that more and more electronics are designed to be stamped together? And that the factory is like this one big-ass 3d-printer that stacks things?
Edited by Keatah, Thu Aug 10, 2017 3:45 PM.