Okay so im pretty sure, since it's been two years, im too late to help you, but anyone else who was hopelessly googling this i hope that i can help because this just happened to me and its crazy how it got fixed. so yes, my buttons worked and everything but my samsung s3 touch screen just would not work or let me draw my passcode. I was panicking i tried taking the battery out numerous times, i soft reset it, i let it just sit. So nothing was working, and i was getting emails and instagram notifications and my phone was vibrating every now and then, but then i got a text notification from the app 'kik' (im not sure if everyone knows what that is, but basically its a free messaging app where you have a username and picture and name and stuff) and i was like "okay lets see if that gave me any luck" and suddenly my phone just worked automatically as soon as i got the kik notification. I don't know if the timing was just coincidental, but im going to have to recommend having someone kik you, and if you dont have kik then try having someone text you, just not through your number and phone messaging. This is really crazy, i know, but for some reason it fixed my phone and i hope it fixes yours too haha
