Added MMU3 - Now Fan Test Fails on RPMs...I
A few months ago I upgraded from a MK3S+ to a MK3.5 and things went well. Last week I started installing the MMU3. I'm having a few glitches along the way, since I don't have room for the extra filament spools and have had to build a shelf for them - plus I have to print a few of the parts with modifications. (Like using a plate holder to replace the printer holder on the buffer and changing the PTFE holders so they fasten to my shelf instead of to the filament holder in the design - so I'm not changing anything on the printer itself.) I also had a print fan on the extruder (the print fan is the one on the front, right?) that had a cracked case, so as long as I had the extruder apart, I figured I'd do a bit more work and swap the fan.
So now I have the new extruder for the MMU on my printer and everything seemed to be working fine. I've updated my firmware:
I decided, as long as I was recalibrating, since I had not only worked on the printhead, but also because I'm switching to a new smooth sheet on the bed, and got a textured sheet, I decided to start at the beginning of all the tests and just check on everything.
I have the new fan on the front of the extruder in place and working. Both fans on the extruder turn on and off at what seems like the right places in the test, but I'm getting this:
It's quite frustrating that it doesn't report which fan is having the issue. I have opened up the cover for the buddy board and plugged in the old fan from the extruder front. I didn't put it on the print head - just connected it and ran the test again. I also loosened all the screws holding the side fan in place. I still get this error. I've done some searching and have found that about 6 months ago there were others with the same issue when they upgraded their firmware.
So both fans are loose, with nothing blocking their rotation. I've even tried the test with the new front fan on the extruder an the older (known working, but with a cracked case) fan loose, on my print table. I'm still not sure which fan is the issue or what I can do about this. Could this be connected with the firmware issue others have had?
RE: Added MMU3 - Now Fan Test Fails on RPMs...I
I had an old fan, with a cracked case, that I replaced. I took that fan and plugged it into the connector in the buddy box and that passed the test. Then I pulled it out and reconnected the one on the print head. It's doing fine now, but tomorrow I'll have a replacement I can use that will take care of the situation for me.
BS solution inc
I had the exact same failure with mine before I updated the firmware of the mmu3 to 3.03.
I am not convinced this was the solution though as it failed multiple times even after that. I stopped the hotend fan (not the print fan that was failing the test) with my finger for a moment during the test (I can't recall if it was before of after the "is it spinning?" question, I think before). On that test it passed after dozens of failures. Why? I have no idea.
mk3.5 fw 6.0.4
mmu3 fw 3.03
When I contacted support they were thinking it was a bug, but we never resolved it together.