Machine won`t fill

my machine empties any excess water at the start of a cycle but won`t refill it stops and leaves the wash program light flashing along with the wash light on the top right hand corner it does this on any wash program i try i have checked the hose and found no blockages
The Dishwasher is a Asko DW1605. The machine will pump out excess water, but will not feed water into the machine. I've checked the water supply pipe which looks OK. I assume its the water inlet valve which needs replacing? Could somebody advise the procedure for testing and changing the inlet valve. Where is the inlet valve located on the machine?