The icemaker in my Bauknecht KGN 7010 F/F has...

Question

The water supply has stopped supplying the icemaker; the mechanism all seems to work ok (I can manually feed water into the freezing ice-making module and when it has formed ice the mechanism tips it into the hopper; But its the water supply to the ice module that has stopped for some reason.) Is this a valve; a relay,microswitch or a blockage problem?

The water comes from a tank which I believe supplies both chilled water (filtered) as well as the ice-maker. The water side of it works fine