Thermal runaway issue with SKR 1.4 and Marlin 2.0

What is the problem?
Getting this error on connecting to a SKR v1.3 with Marlin 2.0 bugfix

Your printer's firmware is known to lack mandatory safety features (e.g.
thermal runaway protection). This is a fire risk.

Learn more at

What did you already try to solve it?

Checked configuration.H

#define THERMAL_PROTECTION_HOTENDS // Enable thermal protection for all extruders
#define THERMAL_PROTECTION_BED // Enable thermal protection for the heated bed
//#define THERMAL_PROTECTION_CHAMBER // Enable thermal protection for the heated chamber

Additional information about your setup (OctoPrint version, OctoPi version, printer, firmware, what kind of hardware precisely, ...)

First time startup on bench without anything but pi connected to SKR. First 3d printer build and configuration with 2.0. Would this error be normal for hotend or bed connected.

Your firmware might have the same signature as a firmware which is on the list of known devices which are missing this future.

To test if thermal runaway protection is enabled on your printer, you can disconnect the heater element of the hotend or the heated bed while printing a print or sending temperature commands to the printer over USB using a terminal to send commands directly to the printer. You can disconnect the heater element while the printer is cold (before start) and also when the heater element is heating up. No heating of the nozzle will take place, so after the period defined by the time constant set in the firmware, the printer will halt if thermal runaway protection is enabled. Power down the machine and reconnect the wires, it is not advised to put them back in on a running machine, as one might touch the open wires; when the printer halted, you should power down or reset the printer anyways. If the printer did not halt, power it down as quickly as possible - TRP is disabled.
(text copied)

That's what can happen if TRP doesn't work

Thank you for the reply however I am doing this on a bench with just the SKR and pi connected. Would I get this error if nothing else was hooked up?

Full serial.log please.

2019-10-07 15:05:41,223 - serial.log is currently not enabled, you can enable it via Settings > Serial Connection > Log communication to serial.log

How do I turn this on via terminal?

You do what it says. Open the Settings in OctoPrint, navigate to "Serial Connection", check "Log communication to serial.log". Then reproduce and share the resulting serial.log.

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Here is the log. Thanks
serial.log (3.6 KB)

You use the wrong M420 command

2019-10-08 12:20:42,795 - Send: M420V1
2019-10-08 12:20:42,806 - Recv: echo:Unknown command: "M420V1"

Thermal Runaway Protection is not enabled in the firmware:
2019-10-08 12:20:38,411 - Recv: Cap:THERMAL_PROTECTION:0

Then, autolevel is not enabled:
2019-10-08 12:20:38,156 - Recv: Cap:AUTOLEVEL:0
Therefore M420 makes no sense (also as @Schnello mentioned, there is an error in that line, there should be a space before the V)
For the same reason (no autolevel), M851 does not work too.

I have no idea where that M command is coming from. Remember this is a first-time setup ever for me.

It was my understanding that all I had to do was uncomment the above lines in configuration.h. Eventually I will want auto leveling and again not sure where that is coming from. Thanks

You know that you have to compile it afterwards, right? Just to be sure :smiley:


M420 S1 should load the ABL Settings.

Just a hunch, but try to also configure it for the chamber, even if you don't have one. I remember a similar case with a non existing bed which wasn't properly handled in the protection reporting code.

And in addition to @Schnello, M420 V1: Print the stored mesh / matrix data

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This is a OctoPrint error. See: OctoPrint tells me that my printer's firmware lacks mandatory safety features, what does this mean?

You don't say what printer you are using so I will assume an Ender 3 for the sake of this discussion.

OctoPrint uses the value found in "STRING_CONFIG_H_AUTHOR" in the firmware to determine what firmware is being used. In the case of the Ender the value is "Ender 3" which is taken to mean the default firmware which does not support therminal runaway. Changing this value to almost anything else should prevent the error.

If you are using a different printer, check the above URL for what OctoPrint is looking for.

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And yet, research the issue and ask others. The printer's firmware may in fact be dangerous.