Thank You for answer! After I see a video in youtube, I touch the board connectors of the keyboard with a screwdriver and the Macbook turns on!! I think that the flat cable of the upper case is damaged. It seems very bent. I put the connection of the upper case in the board very very times, and it doesn't work. Can it be other thing? Now I'm using a Wireless Keyboard, until I know exactly what I have to change in the macbook.