This sounds like a similar recurring problem with my AEG oven. In my case it was the Thermal Cut Out burning out (a bit like a fuse). When it happens the oven basically goes dead.
I have fixed this by replacing this Thermal Cut Out (approx 1" long, 1/4" dia blue plastic covered fuse with four wires, each with an electrical connector). If it has 'blown' it will look a though it has burnt the plastic. Make sure you isolate the electricity to the oven first.
It may be different on a Whirpool Oven - but I think AEG and Electrolux are the same company.
Dennis
July 2006