The pump will not start?

The machine will not pump out the water. You can omly hear a buzzing noise, but if you take away the filter / rince lid and push the pump impeller around, the out-pumping sequense starts.
The pump seems to be of the permanent magnet type. My question is if the pump is broken as a unit or is some kind of controllcirquit broken? Permanent magnet motors need some kind of controlcirquit to start. Or?