water damaged iPhone isn't working after replacing and cleaning (isopr

I replaced the battery, logic board, cameras, speaker, antenna and cleaned the contacts or the whole parts in isopropanol over night. Let it 2 days for dry and put them together yesterday.

By connecting with my Notebook the connection/synchronisation was working. So I could see my music and photos. But the screen stayed black and I could not enter the pin.. While the connection the signal sounded constantly. Where is the problem? Do I need a new battery or new speakers? What can I do now?

Thank you in advance,

bne