Hotpoint Experiance FDEF 51110P

Hi Folks, Hope you can help.
Our dishwasher starts up ok, does a little drain cycle, starts to fill, and almost immediately gets E06 then a short while afterwoods gets the red tap sign,
I read this is a water fill issue, but the water is there, infact it overflows, so I think its the fill sensor, but I cant find it.
Can anybody tell me how the dishwasher senses it is full or filling,
I have tested the spinning wheel sensor, 9vDC when still and 10Vish when spinning and 4.2Khz, does this meter the water or is there another sensor for the water fill.

Its only two years old and we cant get anybody out to fix it.