I had an issue with my S3 today. I dropped it about mid afternoon, but the phone worked after I dropped it. I was driving back to my shop and never got a phone call or text, thought it was odd as I just texted my wife, but did not check my phone. I checked my phone two hours later, seemed to be dead. I thought maybe the battery died, but I never saw the red light blink, nor heard the phone yell at me. Still pondering the idea that it may be dead, I plugged it into a charger (Galaxy Note 1 charger) and it would not show any signs of charging or turning on. I pulled the battery and waited a minute or so, plugged batter back in, did not press any buttons, and the phone went to the 'Samsung' and then the 'Samsung Galaxy S3' logos, but not the secondary 'Samsung' logo with animation nor the AT&T logo.
I tried all the hard resetting, debug mode, and plugging in while battery out stuff. I was upset when I read in this forum that some people thought the phone needed replacement. I started doing anything I could to get the phone to work. I tried taking battery out and plugging in the charger, but a red notification light came on for about three seconds and went off. Nothing seemed to work.
I DID finally get my S3 to WORK!
What I did was, unplugged from charger, took out battery, took out sim card and micro SD card, plugged charger back in, replaced battery. The phone did a full cycle and was working again, all I had to do was put my sim card and SD card back in and restart the phone. My battery was at 58% so no, the battery did not die and get 'just enough juice' to turn on after this period.