Ipad DFU mode, won't turn on when connected to laptop.

Hey guys,

So I got this iPad to repair from a friend. His nephew tried “repairing” this iPad. He tried fixing the screen and replacing the battery. It's in pretty bad shape. When I first got the iPad it was stuck in a boot loop with a red flashing screen before it shutdown.

I opened it up, alot of screws missing, he used some sort of construction glue, LCD screen is very dirty. Disconnected everything, only battery and screen attached, still red flashing. I heated up the motherboard as I feared he bent it when replacing the battery.

After that the iPad shows the DFU screen when plugged into the electrical socket, but when I connect it to my laptop to reset it the screen stays blank and no respons on my laptop. If I disconnect the LCD my laptop does recognise the iPad but fails resetting with error code 1403.

Ampere when connected to electrical socket: 0.50-0.55

Ampere when connected to laptop: <0.10

Seems to me the likely culprit at this point is either the battery (new battery replaced by nephew) or the power IC chip.

Does anyone have any experience with this sort of problem? Or any way to know what steps I can take to further diagnose the problem?

Thanks in advance!

Edit: if I plug the iPad in the wall and preform a hard reset it charges (still on the DFU screen, but I can see it pulling 2,3 ampere). When I connect it to my laptop it starts the restore but after the restart it still flashes red and stops the restore