When i push/pull the switch i can hear the motor, but nothing happens. What could be wrong with the top?[&:]

hmm....hydrolics?

I think it's broken.

I had the same thing on mine. The ram broke where it mounts to the motor itself. Could be whats happening to yours

Check your thread in "General Tech".

You may just be low on fluid. Does the top move at all, maybe just a little?