The ribbon cable is probably the problem. You will have to replace it. Try connecting the controller to a computer running a program that recognizes controller inputs. Use that to troubleshoot.
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The ribbon cable is probably the problem. You will have to replace it. Try connecting the controller to a computer running a program that recognizes controller inputs after you replace the ribbon. You will have to either solder the old one or replace it with a new one and you may have to solder that.
The ribbon cable is probably the problem. You will have to replace it. Try connecting the controller to a computer running a program that recognizes controller inputs. Use that to troubleshoot.