Problem with Dishwasher Diplomat ADP8342?

Hi. Our diplomat dishwasher doesnt seem to be working. When we switch the power button on, it seems to receive power for a few seconds before cutting out. It has power for enough time for us to select the wash program we want, but then cuts out and lights go off before it has a chance to start, usually before we have even closed the door. Any ideas on what could be causing this? Many thanks