Core One L AC Controller Fault - Printer Currently Unusable - Error 35338
Hey guys, I desperately need some assistance with my core one. I was on support chat last night for about two hours or longer, trying to get this error fixed. We tried downgrading the firmware and then re-upgrading the firmware but every time I turned the printer on, I got the following error. This is the Prusa Core One L. I received it in January of this year, 2026, and I've been printing only with PLA up until this week. Then I tried to print PETG for a bit stronger part and got this error.No matter what I do when I boot up the printer, it goes right into this error. Once the boot-up happens, I do get to see the normal control panel for about 1 second, and then it just shuts off and reboots. I'm in desperate need of help with this, and I've spoken with Prusa via chat, but I haven't heard back from them yet. Is there anybody who can help me with this? I need my printer back up and running, and it is a terrible feeling when you spend this much money on a high-end printer and run into a problem like this.I even read online that having a UPS unit plugged into it to get better sinewave electricity would help, so I ordered one that will be delivered on Thursday, but I still would do anything to get this back to normal printing and reliable. I need to be able to print PLA and PETG, and eventually a few other filament types, with dependability. If anyone out there can help me with this as soon as possible, I would greatly appreciate it. I've been a big fan of Prusa for quite a while, and I've had the MK3, MK4, and the regular Core one. I've sold each one of them to upgrade to the newer version and now have this terrible issue, only a few months in. Please Help Prusa!!!! My printer is currently unusable.
RE: Core One L AC Controller Fault - Printer Currently Unusable - Error 35338
http://prusa.io/35338 says it needs to be handled via help chat, if factory reset in firmware, moving some cabled does not help then you might be unlucky and your bed fried and needs to be replaced.
See my GitHub and printables.com for some 3d stuff that you may like.
RE: Core One L AC Controller Fault - Printer Currently Unusable - Error 35338
Thanks for the reply. I've been chatting back and forth with someone on the help chat and am going to send them an email this evening with all the information. If it's something that I can do myself and replace, I do have that capability. Mechanical engineer. Sending it back would be a huge pain. Rather, I would do what I can to get it up and running reliably if possible