Original post by: Zachary ,
Hello Gary, There could be two main problems with your phone due to the water damage. The first is that your LCD screen could have been damaged, in which case you can follow the repair guide for your iPhone [guide|5061|here]. Since you state that using a flashlight allows you to see the screen, I think replacing the screen would be sufficient. The other possibility is that the logic board within your iPhone is damaged. In this case, you can follow [guide|4892|this] guide to replace the logic board. I am not sure how quickly you could find a spare logic board for your phone, but it may be easier (and possibly less expensive) to purchase a newer iPhone such as the 5 or 5s.