How can i fix my dish washer Diplomat ADP 8502?

At the begining of cycle the drain pump empties the sump. When the water is removed (if any) the power light & 70 Deg programme light starts to flash along with pump trying to run in sequence with the on/off & programme lights.
I have checked for loose connections and checked if any water in the drip tray bottom of machine.

LS
January 2011