spilled beer on my controller

Well it's really hard to say, sounds likely that one of the terminals might not be making contact properly and is still be all sticky with beer, did you try alcoholic Q-tip's to get in those hard to reach spaces?

If you do a quick Google search there is actually a lot of similar chases like this that give all sorts of advice, though I would just check the wires leading from the battery terminal to wherever they go are not sticky with beer. If you've already done that then I'm not sure.

To add to DigitalAssasin's reply make sure when you clean it that its Isopropyl Alcohol (IPA) preferably 99% but a more common 91% will still work beautifully. Make sure it is completely dry before throwing it back together (it shouldn't take to long it evaporates very quick). I use this method to clean up rosin flux when i'm done soldering.

I used Isopropyl Alcohol 91% with a large q-tip a week or 2 ago. Don't know where i could get 99%. I got it working again except the dpad. no direction would work on the dpad except left...I opened it up again, tried to clean more and now the dpad left/right won't work but up/down does. this thing sure is temperamental...