My fully integrated Diplomat dishwasher (ADP 8242) is not working. It starts for about 4 minutes then you hear a bleep, when you open the door the first three lights (from the left) are flashing. When you close the door and open it again only the 2 right hand lights are flashing. It does not seem that any water has entered the machine. I have tried switching it off at the mains, checked the filter inside the machine and also checked the pipes at the back of the machine for any creases. My manual does not show any of the above faults. Can you help? Thanks!