I inadvertently jumped into the pool with my iPhone5 in my pocket. It immediately shut down, and a bag of rice didn't help, of course. I took the phone to a local repair shop. They opened it up, aired it out and told me it was fried when it didn't start up. Dissatisfied with the outcome, I turned to iFixit for help.
I ordered the pentalobe screwdriver which arrived 4 days later. I ripped it apart using the tear-down guide. I soaked the motherboard in rubbing alcohol for a couple minutes, brushed all the contact points and reassembled. After a few minutes, the phone booted right up! The flashlight doesn't work and the screen is a little discolored, but everything else is functional!
From start to finish, it took about 3 hours, and I needed to get out magnifying glasses to reassemble. I also wonder if the first repair shop used a pentalobe driver as it was really difficult to remove both of the screws.
My two big pieces of advice:
1) If you don't have anything to lose, $10 bucks plus shipping saved me from spending a boatload of money on a replacement phone.
2) Prepare! I created a grid on a simple sheet of paper and labeled the steps that involved removing pieces/screws. I also placed a piece of tape on the paper to hold the screws in place (I was too cheap to buy the magnetized repair pad). Whichever way you ultimately proceed, be ready and organized.
P5 Pentalobe Screwdriver Retina MacBook Pro and Air
P2 Pentalobe Screwdriver iPhone
iFixit Opening Tool