dishwasher faulty?

I have a indesit DI620uk dishwasher that is broken the thing is that the No 1 and No 3 buttons flash after the machine has filled then emptied straight after one another so not washing anything at all the manual says that these lights indicate that the filter is blocked so i have had all filters out and also ALL pipes from the machine off and checked them all to no avail has anyone got any idea as what i should try next thanks john