I'm having numerous problems. I got an early MK3 and ordered an MMU at the same time, by the time I got the MMU there were already upgrades for it and the MK3 which I got. Because of anxiety I put off doing all the upgrades until recently only to have the MMU not connected. I figured it must be the control board so I ordered a new one, got it last week, and installed it this last weekend only to have the same problem. All the LEDs come on but the printer doesn't seem to know it's there, I can't connect to it via USB either, and I can't seem to flash the printer to the latest firmware because it just seems to freeze up after flashing. With all the upgrades it should be the MK3S+ with the MMU2S but right now it's just an expensive paperweight. Please help.
Check the connections on the Einsy board again. It is easy to swap the filament sensor and mmu connector. Or plug them in in the wrong orientation.
With that odd combination of upgrades it would be better to go straight to Prusa Support who know how they all interact.
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