Fix a (mostly) broken LCD backlight after water damage?
A (very stupid) friend dropped my iPhone 4S (Verizon, iOS 5.0.1) in water about two months ago. It was on for about a minute before I turned it off. At the time the display was blank. Kept it in a sealed bag of rice for about 3 days. After this, the screen worked perfectly for about a month.
So one month ago, the LCD backlight started to fail. First, it worked for about 5 minutes of uptime. Then the amount of time the backlight worked for began to shorten. For a while it worked only while the phone was booting. Then, it stopped working altogether when the phone was on.
However, it still works under the strangest circumstances. The backlight works fine whenever the phone's battery is dead. I can see the "empty battery logo" perfectly. Also, the Apple boot logo briefly flashes (for less than 1 second) during boot.
I wonder if Apple has software code to detect water damage and disable the LCD backlight. Any ideas for repair?