Black/Flickering Screen Fix  

RE: Black/Flickering Screen Fix

Thanks I have a new core one. It ran for about a month then all of a sudden had to lower the refresh rate. I'll be contacting support to report the issue. 

Posted by: @joe3020

I ran into the flickering screen issue below. I saw a few posts that had similar issues and were able to fix it by lowering the screen refresh rate.

I couldn't get far enough into the menus to try this fix, but Prusa Support was able to help me do it "blind" and that fixed it (Huge Thanks!). The steps below are what they sent me (some paraphrase for forum clarity):

Verb Convention:

1 Step=move the knob one click to the indicated direction (for example, 1 step counterclockwise)

Excess = move the knob a lot of steps (so that we reach the final item in each menu)
___
Please restart the printer, then please follow these steps exactly as indicated. If you miss one step, or think you missed it, it's best to start all over.

1. Restart the printer, give it around 30s to fully boot.
2. Excess clockwise, so that we have the selector at the Info Menu.
3. 1 step counterclockwise, this will place the selector at the Settings Menu
4. Press the control knob.
5. Excess clockwise, this will bring the selector to the System menu (not relevant)
6. 2 step counterclockwise, this will bring us into the Hardware menu
7. Press the control knob.
8. Excess clockwise, this will bring the selector to the Display refresh rate.
9. Press the control knob

That fixed things for me and I am back to printing.

If you run into this screen issue, even if this solves it, please let support know so they can track affected printers.

RE: Black/Flickering Screen Fix

I just finished assembling my Core One kit. First print (key chain) went fine. Second print the screen was fine when the job started, but after a couple of minutes the screen flashed occasionally, sometimes showed the screen rotated 90 deg, sometimes displayed correctly for a couple of seconds, but was black most of the time. The print finished correctly. With testing I found that if I left the printer off for 30 minutes I could get a job started before the screen went crazy and the job would keep printing and finish correctly. This seemed to point to a thermal source of the problem. So I removed the cover of the xBuddy box, removed the LCD and its ribbon cable from the printer, laid the LCD and ribbon cable out on the table behind the printer, and connected the LCD directly to the xBuddy board without going through the printer. I also connected the LCD ground to the printer ground with a jumper wire. The display worked fine for a number of prints. So I reinstalled the LCD on the printer, routing the cable through the oval at the bottom of the xBuddy box (eliminating bends/twists inside the box) and straight under the printer to the LCD (not around the side). The display acted up again. Then I noticed that one half of the (split) ribbon cable was kinked in the space between the LCD and the magnetic strip holding the LCD to the printer. I carefully removed this kink and the display has worked fine for half a dozen print jobs. It seems to me that because the ribbon connector in the LCD is perpendicular to the slot for the ribbon cable in the bottom front of the printer, it is extremely difficult to mount the LCD (using the bar with magnets) without kinking the ribbon cable. It is also difficult to avoid kinks in the ribbon cable inside the xBuddy box if you route the cable through the side oval.