Layer fan not turning on when uploading print through Octoprint, SD card print is fine

What is the problem?

I'm not able to get the layer fan to turn on my Anycubic Chiron printer if I upload the file through Octoprint. Saving the exact files to an SD card and printing turned it on at the 2nd layer all 3 times I've tried it so far.

What did you already try to solve it?

Using the latest version of Octoprint with my Anycubic Chiron, sliced with both Cura and Slic3r, the printer will not turn on the layer fan if I upload the file with the normal "upload" and also tried with "upload to SD." Tried 3 separate times slicing with Cura and Slic3r and saved to a physical SD card and the fan turns on at the 2nd layer as coded, correctly each time. I can turn the layer fan on manually in Octoprint when pressing "Fan On" while the printer is idle, but can't seem to turn it on while the printer is printing.

The latest print, I stopped after realizing the fan wasn't turning on so I could try again from the SD card. Tried to print through the printer's touch screen and it wasn't responsive. Turned the machine off and back on and it is printing fine now, layer fan working as normal.octoprint.log (88.0 KB)

Logs (octoprint.log, serial.log or output on terminal tab at a minimum, browser error console if UI issue ... no logs, no support!)

Additional information about your setup (OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible)

If you read your log and search for "error" you'll see that your instance is complaining about trying to talk to the printer and it's getting no response at times.

  • Verify that your printer adapter for the Pi is 5V @ 2.5 and isn't a charger; make sure that the connections are firm
  • You could consider plugging all this into a UPS
  • The serial cable should have internal metallic sheilding or a ferrite core, should be as short as possible, should not have extra adapters inline and shouldn't sink power from the Pi over to your printer board; both ends of the cable should fit firmly into both connectors
  • Obviously, the printer board should be plugged into power and its switch be turned ON