Zanussi DW 927 doesn't fill with water?

I've checked the water inlet valve but there are no blockages anywhere. If I put water in the machine it drains, if I put in water after the drain cycle it will pump through the machine, so it doesn't seem to be a pump problem. The hose is fine and the dishwasher worked perfectly until a few days ago.

I'm thinking of replacing the inlet valve in case it's the solenoid, but I'm not sure whether that's a sensible thing to do, or if there's anything else I should try before spending money?