RPi 3 locks up with SKR Mini E3 V3

Basic Information:

Printer Model: Ender 6
MCU / Printerboard: SKR Mini E3 v3
Host / SBC: RPi 3b
klippy.log

Fill out above information and in all cases attach your klippy.log file (use zip to compress it, if too big). Pasting your printer.cfg is not needed
Be sure to check our “Knowledge Base” Category first. Most relevant items, e.g. error messages, are covered there

Describe your issue:

My system keeps locking up. I don’t know the issue. I have tried several things including

RPi 3b and 4

Different USB cables

Isolating the power connection on the USB cable

Replacing the stock motherboard with SKR Mini E3 v3 board

Different power adapters for the RPi

Adjusted the power output on the printer power supply to 24.2 volts

Zram mod

I just built a new SD card with RPi 32bit lite os and just installed Klipper, Moonraker and Mainsail in that order. After rebuilding the new SD card the SBC locks up just trying to connect with the printer. Because of this I can’t get any log files. I can upload my printer.cfg file. I can get a klipper.log file from the sd card that has 64bit OS.

printer.cfg (3.6 KB)

Hi @LordBond ,

Are you able to SSH into the printer when it locks up?

No. And it doesn’t reply to ping. I removed a lot of the settings in the printer.cfg and just left the necessary items in there. I tried printing again and it printed for about 58 minutes and froze. This time the screen had a banner across the top that said CPU usage was 98% and memory was 36%

I never got the past trying to connect to the printer with the 32bit os so I went back to my original 64bit os card.

Could you please try a clean install of Klipper, Moonraker, and Mainsail/Fluidd using KIAUH? Make sure to back up your config before wiping the SD card. I would flash the Pi 4 with Raspberry Pi OS Lite (64-bit).

I have done that several times with 3 different size and makes of cards. I went back to the original MCU for the Ender 6 and sometimes it fails 45 minutes into the print and sometimes it completes but the quality sucks. I successfully printed benchy but it is stringy on the back side. A lot of times I get lost communication to mcu error. I When I went to bed last night it had finished a print and I looked at it this morning and it looked fine and when I went to get the print off the bed the Klipper screen said lost communication to the mcu. I have a couple log files now. I have replaced everything but the power supply and all the wiring. I have attached the two recent log files.

klippy.log.2025-9-24.log (6.0 MB)

klippy.log (37.3 KB)

This is similar (not enough details to say if it is the same) as my issue. The solution that worked for me was:

adding the line

dtoverlay=dwc2

to the end of the /boot/firmware/config.txt then reboot.

The long original thread:

https://klipper.discourse.group/t/help-klipper-crashes-mid-print/24434/44?u=michaelbrock