Hi Dave, welcome to Just answer
How old is it ?
OK and after 2nd cycle of 30 seconds when you open the dishwasher is the water inside cold or warm ?
have you tried cleaning the inlet valve ?
The valve is located where the inlet hose connects to your unit
do you hear a faint hum from the valve ?
ok, as it wont even fill with water the problem is with the valve that will need replacement
a new one will cost around £35
Yes, this video will give you an idea on how it is done
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