How to identify and fix AEG dishwasher?

Have an AEG Favorit 50750 dishwasher. It started to play up tonight and wouldn't work on any programme when I started it. It would take enough water to fill the tray in the bottom and discharge it if I restarted the programme. Something underneath began to click. I left it for an hour and retried. It then started but made a constant whining noise and wasn't as powerful as what it normally is. It seems to be taking water and discharging water fine. The whine is constant and I'm not sure the reason why it happens but I have heard it on previous recent wash cycles