Chosen Solution
After the phone was dropped down the loo, my wife towel dried and immediately tried to charge!!!! Not working. I have taken apart, dried in rice for a few days and now I only get the start up sequence with mains power applied despite 100% battery symbol. It instantly goes to ‘connect to iTunes’ screen. It will only intermittently power up on USB (3 second apple symbol and then off for 5 seconds) and so I cannot connect to iTunes. I have followed the guides and changed the battery and charging block but the symptoms remain the same. There is no other visible damage and so am I looking at a logic board next?
The Rice thing barely works at all, try a real water damage treatment first,Repairing iPhone Liquid Damage, the guide is for a I 3 but use the same methods on your 4, here is a teardown guide for your phone, iPhone 4 Teardown, good luck, If this Answer is helpful please remember to return and mark it Accepted.
