Blinking logo / Won't start

I bought this in this condition, thinking a new battery would solve it.

It blinks the battery empty then starts blinking the logo only. It will not start it... It will go into download mode but goes right back to flashing the logo after a few seconds.

A new battery did not solve it.

I read somewhere that it is a charging issue and the phone can't power up because it is stuck in the boot mode. One person recommended disconnecting the display cable will allow it to charge then trying again. I started disconnecting cables and found that when I removed the plug on the upper left next to the power and volume buttons that it turned on! The buttons do not work but the tablet does. If I reconnect that cable it goes right back to blinking after about 5 seconds.

I was able to use those 5 seconds and connecting and disconnecting the cable to get the phone into download mode and I reflashed (successfully) the tablet, but that did not solve the issue:(

Any ideas?