Stock device won't boot - possible power issue - PLEASE HELP!
So I have a STOCK (no nothing) Verizon Galaxy S4 that is/was up to date as of 6/23/14. I think the last OTA push was a month or so ago.
A few days ago the device rebooted on its own a few times and I had no clue what was going on, but it stabilized for a day or so. Then yesterday it shut off and would not turn back on - the battery level was at least 80%. I removed the battery and reinserted it. I did not press the power button, but the device vibrates and displays the initial boot screen for about 3 seconds before it powers back off. At least I assume it is powered off - the screen goes black and there is no sign of life. The buttons do nothing to stir its slumber. I can remove and reinsert the battery for the same results.
I've tried POWER+HOME+VOLUME UP once inserting the battery - the blue text appears at the top but again the device shuts off after about 3 seconds.
Charger plugged in shows no light. However, when plugged in, the top part of the device does becomes warm on the screen and on the back with the cover off. - It actually becomes quite warm so I removed the battery but kept it plugged in just to test and it remained very warm. Unplugged now. Also it appears that inserting the battery does nothing now - maybe it's drained.
I'm pretty certain it's a hardware problem at this point, but I have no clue where to start. Has anyone ever had this issue or come across someone that has? I can take the device apart - does anyone know where and what I should be looking for as far as a loose connection or damaged component goes? Is there an electrical component diagram out there somewhere?
Any help is much appreciated!!