Mine went into the pool and was there for a good 10 mins. I immediately took the top off, rinsed it in fresh water and then filled my Pelican case with rice and Phantom and put the rice everywhere I could with the top off. I left it in the rice for 5 days, adding more rice each day. After making sure there was no rice in the phantom, I put the cover back on, put in a different battery and everything worked fine. I turn it off then back on the the motors would not start this time. I had to get a new GPS, installed that and the motors started working again. After putting the props on for a test, one motor would not spin the prop, it would delay. I was worried as I was leaving for 3 weeks and wanted to take it with me. Luckily, I live in South Florida where Drone Nerds is located. After stopping by their shop, I showed them the problem and told them what happened and they said its was most likely the ESC. After purchasing a new ESC and Motor, I was able to catch my flight and. A simple solder of the new ESC and everything is back to flying again just like before. The only thing that I lost was the battery that went into the water, I couldn't get that battery to work again even after it was in rice.
Let it dry out really good and replace anything that isn't working and you'll be back in the air in no time.