I have a 10 year. I have a 10 year old Electrolux Dishlex Global 300. It doesn't complete a cycle,

Question

I have a 10 year old Electrolux Dishlex Global 300. It doesn't complete a cycle, beeps many times then all lights go off and it stops. Then you cannot select a program to restart. It then beeps consistently throughout the day when not even in use. A repairman has tried adjusting electric wire connections, the door handle and checked for motherboard diagnostic faults (which shows nothing). Any ideas?