Taz Pro run out sensor triggering erroneously


I had support for a few weeks but now even that dried up.

Any other owners of the Taz Pro having issues with the run-out sensors kicking off erroneously?

I keep getting “extruder errors” and can’t figure out what is wrong.

On a hunch I turned off the run out sensors and will see if this helps. So far it seems to be working. Any ideas would be great.


The Pro seems to have both filament “run out” as well as “jam” detection sensors. The “jam” detection basically can tell that the filament isn’t really advancing even though it hasn’t run out.

This happened to me with my TAZ Pro … filament wasn’t broken nor out… but the teeth in the hobb gear were full of chewed filament (too many retractions in a short distance). I cleared the teeth, reset the printer, and it was happy from then on.

A can of compressed air works well to blow the chewed filament out of the teeth (since that filament wasn’t never heated …it easily blows clean with air.)

I was previously under the impression that it was only a run-out sensor until that incident occurred.

Correct, the lever is the run-out and the spinner is the jam sensor. I turned both off to get the print to finish.

Just like the nozzle alignment function, backlash measurement, none of these sensors work anymore. I have checked them with multimeters and the appear to be electrically connected so at this point I just turn them off and quit using them.

Could be just bad software.

At this point I have lost 10s of thousands of dollars in the Taz Pros. Whatever it takes to keep them printing to stop the loss!

At some point I am going to have to shut down all printers and start printing parts for the Taz 6s or I am going to get into trouble with those next.


What are the conditions where you keep your printers? Is there a lot of dust? Do you use hair-spray on the bed for part adhesion?

I ask because I’m wondering if your sensors are getting dirty.

All tool heads are cleaned between prints. All printers are in enclosures. Enclosures are positive pressure, filtered air with temperature control. All filament is dried before use according to manufacture specifications. All sensors in question have been checked and despite any dirt or grease, cleaned.

Electrically all failing sensors are in working condition. All connections are correct and no loose wires. I can unplug the sensors and move them to the test bench and read them with Arduinos with zero issues. For the nozzle to cube/leveling washers the electrical connection is proven with a multimeter.

Which is why I believe it may have more to do with Cura and firmware than anything else.

I have one file that I can visually see the stepper for the extruder not turning while printing. I personally checked the g-code and I can see the tool change, I can see the feed rate for the extruder. When I run it I can see the extruder not responding. I can stop the print. Rewind to the beginning and start printing and the extruder responds and does the purge, etc. so the stepper isn’t the issue.

I have another file where the extruder keeps turning (this is with the .8mm HS toolhead) but it throws an extruder error. I turn off both run out and (not in front of the printer so I forget the exact setting name) the jam sensor and the file prints without a problem. Load another file, turn everything back on and it prints no problem. At least the files that do not print do not print consistently so you could debug it, IF you had customer service answering emails.

Many of my prior issues were taken care of by a firmware update Brian sent me, so I am holding out hope this is more code in the system than actual physical problems with the printer.