Hotend not reaching temp w/ new TAZ 3 firmware

I have a TAZ 3 that has up to this point been running a hacked-up older firmware version with now-probably-unnecessary axis speed limits that were added to workaround a hardware issue. That issue’s been resolved, so I’d like to roll back to an ‘official’ version (ideally newest; I seem to recall mention of an issue in older FW that can degrade the hotend heater resistor over time). A couple days ago I updated it following the instructions at .

I un-#defined the LCD support to avoid the 'undefined uint…" error everyone seems to be having (TAZ 3 doesn’t have an LCD anyhow), but otherwise made no changes apart from changing the DEFAULT_AXIS_STEPS_PER_UNIT values according to the paper shipped with the printer.

Everything seemed to go well in the update process, but when I try to print, the hotend does not reach temperature and so the print can never start. It seems to get ‘stuck’ at ~ 1/2 the programmed temperature. The definition enabled for the resistor is “#7” (the default from the downloaded FW; no change needed). Rolling back to the old FW fixes this, although if I wanted to keep using the old FW I would not be trying to upgrade :wink:

Is this a known issue? Or, is there some special trick I’m missing that isn’t mentioned in the instructions?


Have you installed the required libraries in the Arduino IDE? A guide for Windows users can be found here: The TAZ 3 came with an LCD. Are you sure you have a 24v TAZ 3D printer? If your printer does not have an LCD, it may be a clone of a TAZ 3, or an original TAZ 1. Contact support at with your order number/serial number and we’ll be happy to see what was ordered and make the appropriate recommendations from that point.

Turn off the hardcoded temperatures in Slic3r, by going to: Slic3r > Filament settings > Filament > Temperature and set all the temperature options to “0”.

Once we know what specific version of TAZ you have, I’ll be better equipped to recommend the version of Marlin you should be running.

Aha, that is probably my problem - confusion on printer version (somehow I got it in my head that the TAZ 4 is where the LCD/SD were introduced). According to the sheet with the axis steps this one is s/n KT-PR0010-5105 from 6/13/2013. Definitely no LCD/SD.

I’ll try the version for the prior TAZ printers before bugging support :slight_smile:


Don’t worry about bugging support, that’s why we’re here! It sounds like you have a TAZ 1.