LCD screen goes blank - Hardware, firmware and software help https://forum.prusa3d.com/forum/english-forum-original-prusa-i3-mk4s-hardware-firmware-and-software-help/lcd-screen-goes-blank/ Prusa3D Forum Discussion Board en-US Wed, 10 Jun 2026 03:04:49 +0000 wpForo 60 RE: LCD screen goes blank https://forum.prusa3d.com/forum/english-forum-original-prusa-i3-mk4s-hardware-firmware-and-software-help/lcd-screen-goes-blank/#post-782452 Tue, 17 Feb 2026 13:32:19 +0000 On my site i have the same problem with my MK4S like nzsdgb.

But until now i've no solution.

]]> Hardware, firmware and software help Urs L https://forum.prusa3d.com/forum/english-forum-original-prusa-i3-mk4s-hardware-firmware-and-software-help/lcd-screen-goes-blank/#post-782452 RE: LCD screen goes blank https://forum.prusa3d.com/forum/english-forum-original-prusa-i3-mk4s-hardware-firmware-and-software-help/lcd-screen-goes-blank/#post-776314 Fri, 02 Jan 2026 02:11:30 +0000 I also have a similar problem, my screen goes blank when inserting USB drive on two MK4S and a XL.

]]> Hardware, firmware and software help Racenviper https://forum.prusa3d.com/forum/english-forum-original-prusa-i3-mk4s-hardware-firmware-and-software-help/lcd-screen-goes-blank/#post-776314 LCD screen goes blank https://forum.prusa3d.com/forum/english-forum-original-prusa-i3-mk4s-hardware-firmware-and-software-help/lcd-screen-goes-blank/#post-774912 Fri, 19 Dec 2025 19:28:03 +0000 I have a MK4S and have an interesting, repeatable problem.  On startup the LCD screen appears normal during first half of booting (loading bar advances to about half way, fans startup, etc.) then the screen goes black except for faint  backlight and stays in that state.  Printer operates and prints normally through Prusa Connect without the LCD being visible. I have verified all connections and if it was a connection issue, it wouldn't consistently come on every time during bootup and then fail at the same point.  Prior to firmware 6.4.0 if I left the printer on for at least 1-3 hours, the screen would eventually come on and work normally.  Since the update, the screen still comes on during booting and then goes out and will not come back on even after 24+ hours.  Only a faint backlight.  If I hit reset the screen again comes on right away for the first part of the boot up and then goes black with faint back lighting.  Help!

]]> Hardware, firmware and software help nzsdgb https://forum.prusa3d.com/forum/english-forum-original-prusa-i3-mk4s-hardware-firmware-and-software-help/lcd-screen-goes-blank/#post-774912