Hotend fan pulsing during pause despite nozzle being off
Demonstrationvideo;
Steps to reproduce:
Print was paused using the printer’s touchscreen menu. After a while in pause mode, I checked the temperatures: Nozzle target temperature = 0 °C (i.e., hotend is turned off) Nozzle actual temperature ≈ 32 °C Chamber temperature ≈ 27 °C Despite this, the hotend fan turns on for ~1 second every 8–10 seconds, then turns off again, and continues this cycle. No G-code was sent, and no user interaction occurred during this time. After restarting the printer, the fan behaves normally and stays off until the hotend is heated above ~50 °C.
Expected behavior:
The hotend fan should remain off when the nozzle temperature is below 50 °C and the hotend is not active.
Additional notes:
This only happens after pausing a print, not during normal idle operation. It appears to be a firmware-related issue, possibly an inconsistent fan control state after entering pause mode.
Request for clarification:
Is this a known or intentional behavior? If not, is there a fix or firmware update planned? Any recommended workaround for now?
RE: Hotend fan pulsing during pause despite nozzle being off
Demonstrationvideo;
Steps to reproduce:Print was paused using the printer’s touchscreen menu. After a while in pause mode, I checked the temperatures: Nozzle target temperature = 0 °C (i.e., hotend is turned off) Nozzle actual temperature ≈ 32 °C Chamber temperature ≈ 27 °C Despite this, the hotend fan turns on for ~1 second every 8–10 seconds, then turns off again, and continues this cycle. No G-code was sent, and no user interaction occurred during this time. After restarting the printer, the fan behaves normally and stays off until the hotend is heated above ~50 °C.
Expected behavior:
The hotend fan should remain off when the nozzle temperature is below 50 °C and the hotend is not active.
Additional notes:
This only happens after pausing a print, not during normal idle operation. It appears to be a firmware-related issue, possibly an inconsistent fan control state after entering pause mode.
Request for clarification:
Is this a known or intentional behavior? If not, is there a fix or firmware update planned? Any recommended workaround for now?
I've had this happen after a print finishes as well. This is including the 6.4.0-alpha firmware. I'm curious about it as well and open a serial console and dump the log.