I posted my solution to a few similar problems, I'm pasting the same info from my other answer.
Give this a try.
1) open the mbp up and look at the logic board
2) look at the IR/Sleep ribbon cable. (Use iFixit reference guide for logic board installation)
3) Make sure it's plugged in ALL the way. (mine was very loose, nearly unplugged completely)
4) Once the cable is in place, simply reboot :)
This fixed it, so far, seems permanent!
Let me know if it works for you.