belling dishwasher

hi all

have been to look at a belling intergrated diswasher model IDW603

serial 20050800228. the fault is that the ciculation motor runs all the time,select programme shut door circulation motor runs. it has a seperate drain pump and no float switch.no error code just flashs p05 witch is one of the programms, i think it could be stuck on this programm have tried to reset and re select but allways displays p05 then motor circulates.
am i missing something or is control board faulty?