Trouble shooting

[Happyrat]

Just built my Voron 2.4 and every thing works as expected except for the hot end ( a Phatus Dragon high fklow ). When ever I set a temperature from octoprint it immediately does an mcu disconnect.
This obviously sounds like a power or wiring problem but if I swap the heater and sense pins in klipper config so that it thinks the hot end is a "heated bed" and visa versa, then the hot end heats fine but the bed will not.
Also tried powering the Pi from a official Pi power supply instead of the kit one, but no difference. Also tried a different USB C to USB cord between Pi and octopus.
Does anyone have any ideas? I have attached the klippy log file.

 

[Sandman50]

Got EOF when reading from device

This is the error prior to the shutdown. Is there plenty of memory and card space on the Pi?

I've had to use a disk partioner to clean up oddball space allocations on PiOS installs before.

 

[Happyrat]

This is the error prior to the shutdown. Is there plenty of memory and card space on the Pi?

I've had to use a disk partioner to clean up oddball space allocations on PiOS installs before.

Thanks Sandman50. Have tested on new installs with plenty of memory and card space. Same results with both Pi 3B and Pi 4 models. Its a standard octopi/klipper install.
The strange thing is that I can get it to work if I tell klipper its a heated bed instead of a hot end. All other functions work and it is only the hotend that causes this.

 

[Sandman50]

Is your hotend thermistor one from the klipper list?

sensor_type:# Type of sensor - common thermistors are

• "EPCOS 100K B57560G104F"
• "ATC Semitec 104GT-2"
• "ATC Semitec 104NT-4-R025H42G"
• "Generic# 3950"
• "Honeywell 100K 135-104LAG-J01"
• "NTC 100K MGB18-104F39050L32"
• "SliceEngineering 450"
• "TDK NTCG104LH104JT1"

Configuration reference - Klipper documentation

www.klipper3d.org

 

[Happyrat]

I have found the problem. It was all caused by a broken wire in the hot end cooler fan. It was not shorting or anything, just no connection. As soon as I repaired the wire it was all up and working.
I don't understand how that was causing the EOF and time out symptoms but there you go. Perhaps this is something that klipper could fail more gracefully at?
Thank you Sandman for your help.

 

[Sandman50]

Great! Yeah, I didn't think about that one...