I was given an Iphone 4 from a friend at work to see what I could do. She told me that it was dropped in water and she dried it out in rice. Here are the symptoms: 1) It does not turn on 2) when I plug it into the charger, sometimes I will get two successive vibrationsindicating there might still be life in it. 3) the vibrations also occur occasionally after I take it off the charger and I am fiddling around with the phone 4) No lights at all 5) Tried booting to safe mode (hold the home and top bottom) nothing happens. Now, I have taken out the screws and have the battery pack removed from the back, so I am able to disassemble this if needs be. How should I approach the rest of the repair?