Hi, just found this forum.
My nephew took his iPhone 4 to have it repaired after water damage making it totally dead. They got it working by replacing the digitizer, battery. But the power button is completely dead and they said they couldn't get it working. After getting it back he also noticed the front facing camera was stuck (back is fine). I found on this site and others that this is probably because of a missing resistor that probably came off during the digitizer replacement. I see that if I jump this spot with a little solder then the front camera will work again.
My real question is does anyone know if there are any other resistors that are commonly knocked off that disables the power button or is he just out of luck.