I'm having a strange problem with my totally stock S3 with the latest android update. I found it dead in my pocket the other day. It was totally unresponsive to the power key.I tried about 5 different batteries to no avail. When I plug it into a car charger, it shows an empty battery with a frozen 'thinking' circle, then turns off. When I plug it into a Samsung wall charger, it does the same 'frozen thinking circle, ' then appears to charge the battery. While it's plugged in to the samsung charger, I can turn it on. It goes through the boot screens, but crashes during the Sprint splash screen. If I unplug the charger, it is completely unresponsive again. I COULD boot into recovery mode (with the samsung charger plugged in), and have tried wiping the cache. I don't want to factory recover it because the data on the phone is more important to me than the hardware. I can't get it to boot into safe mode.
Today I flashed the firmware with ODIN. ODIN says it was successful, but the phone still has exactly the same problem, except that I can't get it to boot into Recovery or Download mode anymore.
Thanks in advance for any ideas.