I have got Indesit idl40 dishwasher 1st and 3rd lights flashing?

Every time I switch it on the 1st and 3rd lights flash's even after I used soda crystals and plunged it and then I leave it for half an hour then I would plunge it again then switch on the wash cycle and it works some times but most of the time the lights flash's again but there's seems to be a leak underneath as well, can that be the cause of the problem?