Hotpoint DF61 Diswasher not working?

My dishwasher seems to have packed up. I think it might be the timer control unit. I select it to start but all it seems to do is a noise as though it is draining wherever you position the timer switch. Even at the finish stage it doesn;t stop making the same noise. DO yu think it might be the timer unit at fault. Oh forgot to mention, the switch looks like its about to mover to the next position but stays where it is. Please help and where can I get the relevant parts from (if worth replacing), thanks