indesit washing machine wil143s lights flashing?

I have a indesit washing machine wil143s which i recently posted a question about the washer stopping midway through a cycle and some of the green lights flashing and i had a reply telling me the codes.The lights that flash are the green ones from left to right which is 2,3 and 4 all flash and the first light stays of telling me i have a heater relay fault.Does anybody know where the heater relay is and are they easy to fit thanks shaun.Also sometimes the washer won,t stop it just keeps going?