How can I fix my dishwasher Indesit (dont know Model!!! )?

It was in the house when we moved in, been fine but now it sounds like its starting ok, but two green lights (out of the four green lights- that represent the stages of the cycle) are flashing just after it starts, the machine stops but lights still flashing, no water is used or soap taken but I cant even look in the manuel as we havent got one, I have tried emptying filter etc putting on empty rinse but nothing, Please please please can you help?

Kindest Regards
Christina