Jim,
Thanks so much for your help with this. I have replace the display three or four times in the last 12 years and finally decided to replace the power relay board, too. In the past I was afraid to pull the oven out of the wall but you made it seem so easy, I figured I'd give it a try. I pulled the oven out about six inches and removed the black metal cover. Then it was a cinch to replace the power relay board. Hopefully, this display will last longer than three or four years. On another note, before I read your directions, I tried calling Thermador aka BHS. They were absolute jerks. The person I spoke to would offer me no help since I was not a certified technician. I said I wanted to speak to a manager and he put me on hold. I was on hold for around 30 minutes (while I researched your article) and then the call just dropped. Considering this is the third or fourth display I had to replace (I told him this), I thought they would have given me some help. But no dice. Thanks again for your help. And to anyone who's replacing the display, you shold probably replace the power board, too and maybe you won't have to replace the display again.:) :)

Very likely the relay board failed due to that power outage. I'm sorry for such sad news but this relay board is no longer available. You may want to pull out the relay board and check the relay which is responsible for the upper oven bake circuit. If this is just the relay failed then you can fix the problem by replacing just the relay. Otherwise I'm afraid it's time for a new oven.