Can't flash MMU2 and MK3S doesn't recognize MMU2 (N/A on support menu )

Can't flash MMU2 and MK3S doesn't recognize MMU2 (N/A on support menu )  

New Member

I bought the MMU2 upgrade a long time ago but there was no time to assemble it.

Now I bought the MK3S upgrade and finally assembled it. Everything was OK but  flashing the MMU2 firmware failed. The printer itself is working properly.  Also on support menu MMU2 status is N/A

What I did before flashing my  MMU2:

  - I updated drivers on my computer (2.2.7) and Slicer (2.1.0 win64)

  - I downloaded firmware package (3.8.0 (1.0.6))

  - I flashed printer firmware (3.8.0)

Posted : 26/09/2019 8:52 pm
New Member

I was in a similar situation. Took a long time to actually do the upgrade and ended in the same state as you (though with Linux). After confirming through troubleshooting on live Chat that I did in fact do everything right, I'll be getting a new board from Prusa. Worth checking on live chat on the shop site.

Posted : 30/09/2019 5:57 pm
Estimable Member

I also had a similar situation. Mine was not the board, but the cable that connected the Einsy to the MMU-

Posted : 03/10/2019 10:35 pm
New Member

Thanks stephen-h14, I never found that to try. With a modicum of hope I whipped out my multimeter, dupont connectors box and some wiring and started testing, but unfortunately the cable is okay and the board does not flash with it disconnected either.Always fun troubleshooting though.

Posted : 04/10/2019 1:04 am
Illustrious Member
Posted by: @riaan-b

Always fun troubleshooting though.

...same problem. It was a problem with W7, so i changed to Linux Ubuntu 18.04, installed last Slic3R 2.1.0 and flashed the MMU2S successfully. It could also be the USB connection or a bad connection on the mmu2.

Wish you much success in bug searching!

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 19/10/2019 9:24 pm

Another possibility is that you need to press the reset button on either your MMU2 or Printer, to allow the firmware load to progress, 

I had this issue a long time ago, but can't remember which reset I pushed....    I guess it would be the MMU2... but can't guarantee that... 

as the MMU2 and mk3 printer both use different USB cables, are you sure that you removed the printer USB cable before trying to load the MMU2?

regards Joan

I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK...
Posted : 19/10/2019 11:59 pm

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