iPhone behaviour after water damage
I have a 16GB iPhone 4 with water damage. The unit was completely submerged and all the water indictors have been set off.
I'm pretty handy when it comes to tinkering with electronics so when I saw some youtube guides on repairing water damaged iPhones I gave it a shot. The procedure was straight forward and I managed to disassemble, clean and then reassemble the phone with no problems.
There were no traces of liquid left inside the phone as it was water damaged quite a while ago. As stated all the water senses were pink and there was a tiny bit of rust on a couple of screws. Upon inspecting the motherboard the attachment points for the all the ribbon cables were fine in that there was no obvious corrosion on them (that said I cleaned them anyway).
I removed the protective plates from the motherboard and inspected the chips etc underneath. At this point I did notice one site with corrosion at the bottom of the motherboard (see picture the below).
Corrosion spanned the small capacitor (on the right) across to the black oval shaped component (on the left). There is a corresponding mark on the underside of the protective plate, however I'm not sure if it's a scorch mark or a rust mark.
Once reassembled, the iPhone is exhibiting the following behaviour:
-when connected to an AC charger, the phone boots (displaying the Apple logo) and then loads into the 'connect to iTunes screen'. The touch screen is fully responsive and the phone can be swiped to unlock, which then loads the keypad for emergency only phone calls.
-As soon as the AC charger is disconnected however, the phone dies and there is no power whatsoever. It can only be booted whilst attached to an AC charger. Although the phone won't boot without the AC charger, the battery does actually charge whilst connected to the charger.
-when connected to a PC, the phone begins to boot displaying the Apple logo, however it suddenly shuts off. It then boots again and repeats the cycle endlessly.
-the phone can be put into recovery mode, and out of it again using TinyUmbrella. Once in recovery mode, if I connect it to a PC iTunes detects a phone in recovery mode and I can select the option to restore it. Once the restore process start however it soon fails and iTunes report 'error 2001'
I tried a different battery from a fully functional iPhone 4 and it the problems are exactly the same.
The fact that the corrosion was observed down near the battery connector coupled with the fact that the phone will not run without the AC charger to me suggests the damaged components were responsible for transducing battery power into the motherboard.
Finally, I've seen other reports of water damaged iPhones that will boot whilst connected to a charger, but are unable to boot whilst running off battery alone.
At this stage I'm thinking the phone is a shot duck and that the mobo would need replacing, however if anybody has any suggestions or additional info I'd greatly appreciate the input.