My tab 3 10.1" was doing the same as above, not charging even with the original plug/lead .... i took the back off, disconnected the battery and with it disconnected held down the start button for 2 full minutes to clear any charge from the capacitors on the motherboard... i then reconnected the battery and plugged it in, it is now working good as new again! ...
Apparently from all the forums i have read it works as a hard reset when the battery has been allowed to lose all its charge, mine wouldnt even turn on so i am well pleased as it took under 15 minnutes from start to finish.
I hope this helps some of you guys out there
Rick