Nozzle cleaning fail - Hardware, firmware and software help

RE: Nozzle cleaning fail

hyiger — Tue, 21 Apr 2026 15:53:06 +0000

Posted by: @gezz
I was similarly frustrated with this issue thinking I would need to pull down and clean the extruder, I did a number of cold pulls (very simple using the inbuilt software ) and this solved my issue. Also new firmware was updated. Hope this helps .....
NB I tried an assortment of remedies but the above has worked ........

Usually I use a brass brush to remove debris from the nozzle head. That generally works for me. Also, a nozzle wiper mod will help versus smooshing the nozzle against the sheet.

RE: Nozzle cleaning fail

Gezz — Tue, 21 Apr 2026 15:50:25 +0000

I was similarly frustrated with this issue thinking I would need to pull down and clean the extruder, I did a number of cold pulls (very simple using the inbuilt software ) and this solved my issue. Also new firmware was updated. Hope this helps .....

NB I tried an assortment of remedies but the above has worked ........

RE: Nozzle cleaning fail

Flutelab — Tue, 21 Apr 2026 10:15:02 +0000

I often have nozzle cleaning fails, and I see the printhead hovering around 70mm over the bed for a while before giving the error message. ususally works on retry but I have to babysit the printer. Could this be a load cell failure thinking it has already hit the bed ?

RE:

hyiger — Sun, 25 Jan 2026 15:43:04 +0000

In PrusaSlicer switch to Expert mode. Then in Printers -> Custom G-code -> Start G-code look for G29 P9 X208 Y-2.5 W32 H4 and add a ';' to comment it out. You should only do this if you install a nozzle wiper. Otherwise the bed mesh could be inaccurate due to filament stuck to the nozzle and could possibly cause first layer adhesion problems.

;G29 P9 X208 Y-2.5 W32 H4

RE: Nozzle cleaning fail

Norbert — Sat, 24 Jan 2026 21:13:58 +0000

And how do I disable the nozzle-Cleaning G-Code?

RE: Nozzle cleaning fail

hyiger — Sat, 24 Jan 2026 21:02:42 +0000

I would recommend printing a nozzle wiper and disable the nozzle cleaning g-code.

RE: Nozzle cleaning fail

Norbert — Sat, 24 Jan 2026 10:27:45 +0000

Posted by: @nessuno0505
Firmware 6.4.0, nozzle cleaning more reliable when printing PETG, but unreliable with Varioshore TPU, standard Prusa profile.
The varioshore TPU always oozes a bit at 210-220°C, so the nozzle cant't be 100% clean! If I let the cleaning nozzle fail and then choose "ignore", the printer prints flawlessly without issues.
What is the purpose of the nozzle cleaning? It's not a cleaning by the way: the nozzle touches the bed a few times, it's not a good method to "clean" IMHO.
I know there are mods and g-code lines to add to have a proper "cleaning", but the prints are good even if I skip the cleaning (at least with varioshore TPU), so why bother to clean?
Nevertheless I'd like to know more about this... bug? Is this a bug?
Thanks.

For me it's the same. I tried all tips but now I simply ignore the error and it prints perfect. I'd like to skip the whole nozzle cleaning nonsense.

RE: Nozzle cleaning fail

Nessuno0505 — Fri, 26 Dec 2025 20:20:08 +0000

Firmware 6.4.0, nozzle cleaning more reliable when printing PETG, but unreliable with Varioshore TPU, standard Prusa profile.

The varioshore TPU always oozes a bit at 210-220°C, so the nozzle cant't be 100% clean! If I let the cleaning nozzle fail and then choose "ignore", the printer prints flawlessly without issues.

What is the purpose of the nozzle cleaning? It's not a cleaning by the way: the nozzle touches the bed a few times, it's not a good method to "clean" IMHO.

I know there are mods and g-code lines to add to have a proper "cleaning", but the prints are good even if I skip the cleaning (at least with varioshore TPU), so why bother to clean?

Nevertheless I'd like to know more about this... bug? Is this a bug?

Thanks.

RE: Nozzle cleaning fail

Krieger — Tue, 23 Dec 2025 22:03:36 +0000

I was having nozzle cleaning failures. I could clean the nozzle and it might work, but then the bed probing would fail. Support is sending me a new main cable.

In the meantime, I found this thread on github https://github.com/prusa3d/Prusa-Firmware-Buddy/issues/4596

In it there is a user suggesting that the heater is inducing current and causing a disruption on the loadcell signal. The solution is to remove the main cable, depin the heater wires from the connector, create twisted pairs, and re-insert the pins into the connector (be mindful of polarity).

I did this, and now my printer that was a paperweight is happily printing again.

RE: Nozzle cleaning fail

Raaz — Sun, 22 Jun 2025 12:33:16 +0000

Turn power back on and home the printer. Note: Not Z homing.

*calibration.

Z-homing happens at every start of a print, when the bed moves against the nozzle. Calibration is when the bed is moved against the bottom with a lot of noise.

Not meant as being a smarta**, I just confused the two things myself so want to clarify.

If you want to permanently fix this, there are mods for the bottom of the Core One to level the bed during Z-calibration. Not sure that's time well spent, but there are nice dust/filament-pieces cover combinations.