F2 fault code adp 8332 diplomat?

i have a new machine,purchaced 3 years ago,fitted it just before christmas 09,1st wash fine,since then the machine does the pre wash ok,draines to next stage,you can hear the water entering the machine,it starts working,but at various times the washer seems to be cutting out,saftguard cutting in ?does this for a while,and then displays F2,i have checked for water in under tray,its dry,and no leak aparent when machine running. any ideas please ??