RE: Mk4 screen goes blank after some time
OK. It may be a good idea to separate the motor and display cable and run them as far apart as possible. The case also concerns a PE wire (greenish-yellow) running parallel to the display cable. Only God knows what interference can take place along this wire. And perhaps there is a mistake in the Buddy design, when the individual connectors are uncomfortably placed and the cable is unnecessarily crossed. It might also be a good idea to add ferrites to the power cord to limit interference from the mains. I apologize for the post written in Czech, I do not know how it got there.
RE: Mk4 screen goes blank after some time
OK, switch back to English:
EMC problems are always a layout problem, whether PCB or wiring. It's always nice to take a "step back" and look at the bigger picture, but most of the time it's really just a problem of a pin connection on a connector or defective capacitors. What happens is that the supplier delivers a bad batch that doesn't adequately catch voltage spikes from interference, etc. However, without proper analysis and measurements we can only make crystal ball guesses here.
RE:
If you are comfortable with unscrewing a few screws and doing 20 minutes of work it's a pretty easy fix, just be careful with the thermal pads on the back of the board, and lay the cables flat so that you don't put pressure on the board when screwing it back in!
Does that still work for you? 🙂
Yep! I'm away from home now, when I come back I'll probably post how I routed the cables here, I hope I remember 🙂
The ferrite idea is great too, I have some spare ferrite cores as they solved a similar problem I encountered a while ago. I should have remembered!
RE: Mk4 screen goes blank after some time
Posted by: @neolker
OK, switch back to English:EMC problems are always a layout problem, whether PCB or wiring. It's always nice to take a "step back" and look at the bigger picture, but most of the time it's really just a problem of a pin connection on a connector or defective capacitors. What happens is that the supplier delivers a bad batch that doesn't adequately catch voltage spikes from interference, etc. However, without proper analysis and measurements we can only make crystal ball guesses here.
I had the same discussion in another forum with someone who does stuff like that for a living and he also supports your theory that it must be a problem with a connection etc. and not with interference. He also said it was just guesswork at this point without measurements.
Yep! I'm away from home now, when I come back I'll probably post how I routed the cables here, I hope I remember 🙂
I did that and it didn't work. Maybe you fiddling around with the cables established the contact for a non-ideal solder or something like that.
RE: Mk4 screen goes blank after some time
@lfachaux - The ribbon cable's around 20" long.
RE: Mk4 screen goes blank after some time
I searched if someone has encountered this kind of issue on the mk3s and :
https://www.printables.com/fr/model/391172-ferrite-mount-for-prusa-i3-mk3s-lcd-ribbon-cable
@Brandon thx for the information
RE: Mk4 screen goes blank after some time
seems to be a very intermittent issue for me. i have also printed multiple items with no issue but then my last print for a filament guide for one of my MK3s the screen went blank but as the print progressed it redrew the image line by line (if that makes sense)
My kit that I just got finished yesterday, with the new PE wire location, works with no issues so far. Powered up, ran through the startup wizard, and then did a 1.5 hour print followed by a 13.3 hour print, followed by a 1.2 hour print. Zero issues seen on the LCD during this time.
RE: Mk4 screen goes blank after some time
I wonder if it might help if the firmware could perhaps be patched to frequently refresh the image, which could mitigate the problem. I suspect it'd cause really awful flickering, though.
RE: Mk4 screen goes blank after some time
I assembled my MK4 kit (xLCD version B) last Thursday. On the first start I updated the Firmware to 4.7.1 and the xLCD worked flawlessly during the following selftest. My first print was a Benchy and there the problem began with the xLCD. It went b/w + inverted and it seems that not every pixel was properly addressed. For seconds it content was the mirrored on the y-axis (I haven’t made a picture of this).
It went black and at 3% it started to shows partially some progress in colour. First the bar on the right side with the percentage showed up, then the horizontal part of the image (see picture) and afterwards the remaining time (not to be seen in picture). After minutes it went completely black for the rest of the print. The print itself was good.
After a reset the xLCD was working again and shoed soon the same problems and went black. I was completely disappointed and moved the printer into the shelf and started to search for others with the same problem and found this thread. Yesterday I tried to reproduce the issue with the xLCD and the problem with it was gone. I printed two Benchys without any problems so far.
MK 3 -> MK 3S -> MK 3S+ & MK 4
RE: Mk4 screen goes blank after some time
Hi guys, as I said before in my previous comment I think I had some problem with the socket soldering. I received a new display from Prusa (ver. A, before I had ver. B) and now everything works well. So my problem is solved and I don't think it was caused by some interference.
RE: Mk4 screen goes blank after some time
Hi all, I have now the same problem (ver B).
The display worked at the beginning and it went black in the second print after 30 minutes. In the third print after 10 minutes and now it does not work at all. The display flickers, the menu is shown only partly or a white/black background.
Reconnecting the lcd cable without attachments and updating the firmware to 5.0 alpha did not help.I alos doubt it has anything to do with cabling/interferences.
Support will come back to me on Monday, I hope they will also send me a new board.
RE: Mk4 screen goes blank after some time
Hi all,
I managed to solve my screen issues reported here:
https://forum.prusa3d.com/forum/postid/663158/
By doing the following: check your lcd pcb is properly seating against front cover. You need to be super careful with its screws and not overtighten one edge and not to deform it. I found that slight deformation to it will cause it to be not stable, fail to boot and etc. It was the issue for me (not cables, not EMI issues or etc). Running free weeks now with no single issue. I hope it can help to some of you.
RE: Mk4 screen goes blank after some time
Hello,
I experience a similar issue on a MK4 kit. It worked fine on day 1 and then started to work erratically. After talking to the support, they ask me to send pictures of the board, unconnect/reconnect everything with no luck. When motors are not connected but only the harness for the loverboard/extruder, the LCD was still buggy therefore issues from motor interference were quickly discarded. The ribbon and PE cables were also checked and were unlikely to be the cause of the problem. Customer support is sending me a new LCD board, a new cable and a newly designed printed part. I'll see how it goes.
RE: Mk4 screen goes blank after some time
Same thing here, got the new revision lcd and it seems to be working again so far …although my original lcd did work for a week before it started acting up, will let you know if it starts again
RE:
I'm almost completely certain that it's interference at least in my case as it happened exactly when the motors activated, and never when they were off. Fiddling with the cables and connectors while the printer is on doesn't have an effect at all, I tried. It's probably a connection issue for some people, as it seems like it can be caused by multiple things. For me, it's almost definitely interference
RE:
Earlier in this discussion you can find my comments about my original printer, which I will try to recap here.
1. I received my initial printer and immediately had had issues with the screen going black, scrambled information on the screen, and at times the text would reverse, like you were looking at the screen in a mirror. I also had to instances where the printer would lock up during a print. I replaced the PSU on this printer, which DID NOT fix any of the issues, so I asked Prusa replace the printer, and they did. (This printer was in this enclosure the entire time I had it...
2. The new printer arrived and I decided to quickly set it up on a bench to make sure this one worked. I ended up stacking up days of printing while the printer was setup on this stone surface bench. ZERO issues, and the printer worked flawlessly. After weeks of printing, I decided to cleanup my setup and get the printer setup in my enclosure. After placing the printer in the enclosure, I immediately was back to all the screen issues discussed in this thread, and all prints would fail within minutes. I fought with this for ~1 hour, reached out to support about the issue and we started digging into the issue.
3. The next day I decided to remove the printer from the enclosure because I was planning to return the printer and be done with the mess. After removing the printer from the enclosure, I tried some test prints, and everything is back to normal. Now I have been running the printer for many weeks outside the enclosure and it hasn't had a single hiccup. My prints are fast and the results are better than my MK3S+.
I should note, my MK3S+ and Mini run in this enclosure with no issue. Draw you own conclusions from this, but it sure appears to be an environmental issue, not bad connections and/or firmware.
RE: Mk4 screen goes blank after some time
Also have this problem.
The screen goes blank and flash white from time to time.
This does not happen every print, but maybe 1 time per day.
I have to power off the printer and turn it back on and the screen works again.
This happen when printing from USB stick or Octoprint to USB-C
Support is sending me a new screen, but i looks like that the new screen also have the problem, out from what i read in the thread 🙁
But the support i talk to, said it was important the printer was earth properly.
My apartment is old and don't have earth in the outlet, so could this be the root cause?
Could be fun to know if all that have this problem is because the printer don't have earth connection?
RE: Mk4 screen goes blank after some time
I don't think that "earthing" or "grounding" is as necessary as support is making it sound. They are probably trying to eliminate potential issues. The MK3's never had that grounding wire, and when I asked support about it, they told me that it was not necessary and I could actually remove it. My printer is on a sailboat connected to my battery bank, but no specific earthing for the printer and I have had no issues.
But the support i talk to, said it was important the printer was earth properly.
My apartment is old and don't have earth in the outlet, so could this be the root cause?
Could be fun to know if all that have this problem is because the printer don't have earth connection?
RE: Mk4 screen goes blank after some time
Update from me: They sent me a new screen (Revision A, before I had B) and it works. No more problems. So no electrical or whatever stuff. 🙂
RE: Mk4 screen goes blank after some time
Oh, it does not sound good either.
During the MakerMuse YouTube Live Streaming for Prusa Assembled MK4 unboxing he got a similar issue. The LCD went suddenly black and stopped to work. 😨
Here is few seconds before it happened...I couldn't image the expression of Joseph if it was looking the live streaming in that moment... 😏 (as Murphy's laws teaches....)
Then he was able to fix the LCD by chance by playing around with the cables. Look at the video.
Regards
Thanks for sharing!! Had the exact same problem as Joseph in the video. However, the screen was functional for almost 2-3 weeks after assembly of a MK4 kit. In my case, the screen functioned normal during boot screen, then gets black as soon as the system starts. Then sometimes flashes or randomly menu items appeared. So I did the exact same thing as Joseph in the video: tilted the printer back, pressed an all connecters on the LCD board, which solved the issue 🙂