Notifications
Clear all

MMU MCU ERROR prusa.io/04306  

  RSS
reed.spin
(@reed-spin)
Member
MMU MCU ERROR prusa.io/04306

Mk3S+ with MMU2S on latest firmware. 36 hours into 48hr single material print received "MMU MCU error prusa.io/04306" with beeping and request to confirm Reset. Contacted PRUSA support chat, they weren't sure if print could be salvaged.  Ended up confirming the Reset and printing continued to end without issue.

On the MMU2S checking connections after the Reset and print finish; you can recreate the error by wiggling the MMU board connector with 2-black and 2-red wires. Held down the connector lock and exercised the connection ~6 times. Followed by another 40+ hour print and prusa.io/04306 error no longer happened.

Posted : 16/01/2024 12:44 am
BaconFase and RRinMI liked
RRinMI
(@rrinmi)
Member
RE: MMU MCU ERROR prusa.io/04306

I had exactly the same error and your post nailed the solution.  I pulled the connector, put a dab of alcohol 0n the pins with a Q-tip and moved it around a bit.  Thank you!

Posted : 18/01/2024 1:44 am
Lukáš Kupec
(@lukas-kupec)
Member
RE: MMU MCU ERROR prusa.io/04306

I have exactly same issue, with intermiitent "Selector cannot..." "Idler cannot" and I have narrowed it down to the cables/connectors. I think a strain relief here would help.

Posted : 31/01/2024 8:24 am
JoanTabb
(@joantabb)
Veteran Member Moderator
RE: MMU MCU ERROR prusa.io/04306

try petroleum jelly (vaseline) on the pins to prevent further oxidation!

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 : 31/01/2024 9:45 am
Lukáš Kupec
(@lukas-kupec)
Member
RE: MMU MCU ERROR prusa.io/04306

I just discoverd https://github.com/prusa3d/MM-control-2.0/issues/15

Voltage drop on the connector would make the highlighted issue even worse, which is pretty consistent with what I am experiencing.

Posted : 31/01/2024 10:14 am
Robin
(@robin)
Prominent Member
RE: MMU MCU ERROR prusa.io/04306

It's getting more and more clear, that this kind of behaviour is what ended in "all LEDs blinking" with the old firmware. If you just update the firmware and do not mod the MMU2 with an additional power supply (DC converter) or short the diode or install the new pd-board you will still get the voltage drop, crash one or more TMC driver and have this kind of errors...

If at first you don't succeed, skydiving is not for you.

Posted : 06/02/2024 9:31 am
Lukáš Kupec
(@lukas-kupec)
Member
RE: MMU MCU ERROR prusa.io/04306

Just got the PD board installed, had to remix the idler body so it works both with the PD board AND the rest of the old MMU2 printed parts.

see here: https://www.printables.com/model/753443-mmu2-idler-body-compatible-with-pd-board

I am running some tests and so far so good.

Posted : 06/02/2024 11:39 am
Share: