Water damage and possible diagnosis!

Toby hughes, the first thing to do is to not try to start it again. Disassemble it by using this guide. Clean all parts with +90%isopropyl alcohol. By now you may even already have corrosion damage, use a soft brush to clean the logic board, the connectors and the cable ends. Look for any components that look burned or are broken. Replace the battery and reassemble. Now re-evaluate and see what you get. It is possible that the cleaning will resolve the issues, but further trouble shooting may be need. There is a chance that you will need new displays, that you fuses may have burned out etc. Again start with cleaning, a new battery and re-evaluate. Let us know what works once that is done. Hope this helps, good luck.