Note 2 won't get past black splash screen/AT&T update loop

[and55note]

Hello,

I have a rooted phone that has been humming along nicely for several months. It was charged to 80% this morning and now will not turn on fully. If I remove then replace battery then hold down the power button it will get to black '"Samsung Galaxy Note II" screen then go back to a black screen which seems to be powered off and not respond to anything.

I got it into recovery mode "Power+Volume Up+Home" and it writes some commands then goes to a black screen with an AT&T logo and says "Updating" and get to 100%, restarts and I'm back at the stuck black '"Samsung Galaxy Note II" screen, it goes black and will not respond to any keys. I did get a System Update notification last night from AT&T but declined it.

Any ideas on what I can try next? Thank you!

 

[Rukbat]

Volume Down+Home+Power. See if it gets into download mode. If it does, see [Samsung] How to flash Stock ROM via ODIN. (Reflashing a Samsung ROM is boring enough to kill you, it's not as difficult as tying your shoes.)

If it won't flash the stock ROM (especially if you get a NAND Write Failure), the hardware (on the motherboard) is shot. Considering the price of a used one, even if you can do the repair yourself, it hardly pays if that's the problem.