Originally Posted by Odinuts
I don't think it's been water damaged before but I did have some issues with the USB port where the phone randomly thought it was charging when it wasn't even connected to a charger but I fixed that using a toothpick to clean up the port. Device isn't in warranty anymore, unfortunately. But I recall having to go to stock before and doing the data wipe and factory resetting process, so it's all kinda weird.
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Try this :
BOTH IN STOCK and CUSTOM ROM (After Following proper instructions provided by OP to install ROM)
a) Try whether your phone does boot up again after switching off again ?
b) If you can enter recovery when phone is switched off ?
POST results here..
If the problem persists only in custom ROM not in STOCK then its SOFTWARE ISSUE..
IF still this Problem is in Stock ROM too then its HARDWARE PROBLEM ..
Take your phone to the Local Repair Shops to check for USB and MAINBOARD .. according to the results ofcourse..
Hit Thanks if i help u