LCD not working

Updated 10 days ago ​by Tomáš Chvalina

Power down the printer and unplug your USB cable if connected. Open the electronics covering and examine the wiring diagram.

If you see strange/ garbage (garbeled) letters on the LCD or LCD is blank.

Check that your LCD cables:

  1. Are properly plugged to the miniRAMBO board (make sure that the red cable is the top one)
  2. Are not badly warped or damaged
  3. Are making good electric connection on the miniRAMBO board or EINSY miniRAMBo


Last thing before contacting info@prusa3d.com is to unplug both of the LCD ribbon cables. Laying them down on a flat surface and gently stretching them. Then plug them back and see if it makes any difference.

If you see squares on the LCD

Check that you have:

  1. Uploaded to the proper firmware version 
  2. miniRAMBO 1.3a (all of the i3 MK2/ i3 MK2S) 

Do not hesitate to contact us at info@prusa3d.com if you would have any following questions.


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