reset the SMC works but you need to follow this and to do all the steps in the way i describe (for macbook pro with removable battery): 1 - Remove the battery with magsafe connected 2 - Remove Magsafe 3 - Hold start button for at least 5 seconds 4 - plugged Magsafe connector 5 - plugged the battery The light change green to red. Wait 10 minutes and the computer start ! See ya