iPhone 4 water damage

tim, the very first thing I suggest is that you stop using the device, (remove the battery) and totally disassemble it, follow the guides on here. Then clean it with +90% isopropyl alcohol. This will displace the water and stop corrosion. It it okay to submerge a board in isopropyl alcohol. Here is a guide for that. Even so it was written for a 3G, the procedure is still the same. After that, air dry all the components. Do not forget to clean the connectors on the board as well as the cables. Then re-assemble with a new battery This is not optional but a must to avoid failure later on. " Check your board for any missing or damaged component. Water damage is the toughest to trouble shoot and to repair. Hope this helps, good luck.