Bosch Microwave Display Is Out

[maladu]

The display on my Bosch microwave went out. This is a known problem with Bosch microwaves so I purchased a new display (incl. mainboard) from Bosch directly. I plugged that one in but the display is still out. Hence, I suspect it's not the display/mainboard. What else could cause that? There doesn't seem to be any fuse. The breaker in on. 

[Vance R]

Model number would make it easier to help. Generic help is no power to mainboard.

[maladu]

Sorry, forgot to mention that. It's an HMC80251UC/01. Where could power to the main board be interrupted? The breaker, dedicated to the microwave, is on (and I flipped it a few times as I was swapping the displays). There doesn't seem to be a fuse in the microwave, either. I was thinking of checking the voltage to the board but I there aren't any good access points. Maybe if I dismount the main board I can access it from the back.