Bosch 800 Series Combination Oven + Speed Oven failure. Installed Nov 2016. May 2020 the speed oven lost all power while the lower oven still worked fine. Searching the web, I saw others have had similar issues that originate with 1 or more of the 3 door switches failing for the speed oven, which then blows the internal fuse. Always flip the circuit breaker off before servicing any electrical appliance. Pull out the oven far enough to access the full top panel. Internal fuses (2) are located under the top panel at the back right corner. In my case it was the left-most 20A microwave fuse (positioned perpendicular to front of oven). There are 2 switches activated by the left door latch and 1 by the right door latch. You can access them with the top panel removed. They are positioned in plastic mounting brackets that can be removed to pull the switches to a better position to work with. The red or green activators should click when pressed and fully return when released. If stuck or no click, it is faulty. In my case it was the green switch at the left side upper position. I also confirmed the switches worked or didn’t with my multi tester. The mounting bracket tabs for the switches are fragile and it will save time to order a new bracket(s) with the switch(es). After replacing the green switch and fuse, connecting everything back up and turning the power back on, the display lit but the # pad and micro functions didn’t work. Shutting everything down and pulling the oven back out, I saw/heard that the left door latch was not fully depressing the lower red switch in the new bracket. If I pushed the door in with pressure it would click, but if I released pressure it popped back up. Everything was positioned as it should, just shy of closing the switch when the door closed. I had to insert a tab spacer that the latch would push to activate the switch. If you have to do this, make sure that the switch opens when the door opens, as this shuts off the microwave when the door is opened. I am disappointed that a $3000 3-1/2 year old oven would have switches that fail this early. The speed oven also suffers from the reported “dim display” issue. When that goes, we likely will detach the speed oven from the lower oven, rebuild our cabinet for the lower oven, and replace the speed oven with a countertop microwave. It won’t be from Bosch.