Blank iPad not restoring, Serial Number n/a, "Waiting for iPad". Help?

Aunts 64GB Wifi iPad2 went blank, IOS unknown. Tried other cables and PCs. Antivirus disabled. iTunes recognises iPad2 but serial number n/a. Suggests restore so agree and iPad shows apple logo and progress bar. Progress bar does not progress and iTunes says "Waiting for iPad". Stays that way forever until unplugged when after a few minutes it goes blank again.

As it is outside warranty and paying for fix is outside budget, I opened it and reseated all connectors but this did not fix it. I Baked the motherboard at 250Deg C for 10 minutes but that did not fix it.

Is there a component that can be replaced to fix this? Or if I applied flux and locally reheated and reseated a specific IC maybe?

Basically, does anyone know what causes this fault so I can target a solution?

Thanks in advance,