flashuing lights?

i have a hotpoint aquarius model no wf541 and the on/off,rinse hold and mini load button keep flashing .. I have been told by the manual and by other people to clean fillter now i cleaned the filtter at teh front my unscreawing the cap and cleaning it out and there was nothing in there and the water is getting throw but it is still doing the same problem can anyone help as i dont want to pay a arm and a leg to get it fixed