you cant repair this fault as the circuit board has failed and is totally useless. The only way to rectify this is to replace the board,the cheapest price is from E spares at about £153, the factory reset wont work with this problem as the program memory has been erased due to the failure of the main board in the control unit. It's a common fault on smeg dishwashers that are over 4 years old.
the dishwasher man, June 2009