iPhone 5 not detected in iTunes

Hello all,

I've been having an issue with an iPhone 5 which would not turn on after battery was depleted and after replacing the logic board from a working donor phone; this solved the issue but afterwards, although being charging on all usb ports I've tried on, I cannot for the life of me have iTunes detected. I've since then tried the donor lightning connector assembly on this unit, the original logic board on this unit, all combinations and still nothing.

Can anyone help me isolate the issue?

Thank you for your help.