I didn't change my home button, but I just got Error 53

I was repairing my iPhone 6 Plus' screen and when I finished, Touch ID seemed to be failing every time I tried to activate it. I tried updating to iOS 9 and halfway through it iTunes shot out error 53. I've been looking around and from what I gather it's a problem with Touch ID. But why is there a problem in the first place if I didn't change my home button? If I fix Touch ID with a new extension flex for example, will it clear the error? Only my home button was working before my attempted update, but not Touch ID. Any help is appreciated.