DI 74 EL Motor Problems

[Alf G]

Hi, I have an Indesit Dishwasher DI 74 EL with a problem. We have particularly hard water here and the dishwasher refuses to operate. The sequence is now thus: -

1. Cycle resets
2. Water drains from the dishwasher
3. resevoir fills up.
4. Cycle should now start but all I now get is a loud humming like a large current is being drawn and that is it until I switch it off.

I know its a long shot but can anyone point to a specific component?

Cheers