<p>Due to a mains power failure, I was unable to finish a &quot;Thingiverse Stripes&quot; auto bed levelling test on my new Ender 3 v2. When power returned several hours later and I tried to resume the Test, I discovered that the Bowden tube and nozzle were blocked.</p>
<p>I replaced the Bowden tube and nozzle but now found that after the first inch of the print layer the filament stopped, and the extruder stepper motor was not working. I checked that I could operate the extruder with the manual wheel to prove that there was no blockage and it worked ok. I also checked the extruder stepper motor in the &quot;Move&quot; mode; It would not turn in either direction. I think it tried to move but stopped instantly.</p>

CC BY-SA 4.0
2022-09-26T05:07:33.633Z
Check whether all the cables are properly attached to the pins in the connector.
Also, was the hotend heated while trying to do this? Some firmwares leave the pointless "safety feature" active to prevent extruder motion if the hot end is cold.
towe
CC BY-SA 4.0
2022-09-26T08:59:08.810Z
I checked that all the cable connections were good. However, I was following a youtube video instructions and I'm now pretty sure that the hotend was COLD when I restarted the print after the power failure and that is what caused the blockage. I have already seen your message about the Marlin "Pointless safety feature" but, as an old (81) novice, I have  no idea how to follow your suggestion. I would really appreciate some guidance please? Tom.
Tom
CC BY-SA 4.0
2022-09-26T09:03:53.317Z
The feature is hard-coded into the firmware - to change it permanently, you'd have to compile a new one. It's also usually not an issue, but can be frustrating for beginners who don't know about it and wonder why their extruder won't move.
In current Marlin, it's called `PREVENT_COLD_EXTRUSION` in the configuration.h file, which may be commented out to disable it.
There's also a g-code to disable it semi-permanently: Sending `M302 P1` will disable the check, `M500` lets you save that change if saving settings in the EEPROM is enabled in your firmware.
towe
CC BY-SA 4.0
2022-09-26T09:38:31.697Z
Thank You towe, as I understand what you suggest, the fix, "send M302" and "M500" must be done in Marlin and not in Cura. I wil now try to find out how to do that. Thanks again. Tom
Tom
CC BY-SA 4.0
2022-09-26T09:40:21.860Z
That fix, sending `M302 P1` (the `P1` is important) and then `M500` can be done in any program that can communicate directly with the printer. I used to use "Pronterface" for that. You could also put those commands in a normal text file with the file ending ".gcode" and run that from an SD card.

Also, note that there's no immediate need to disable that feature, as long as you remember about it before wondering why the extruder might not work.
towe
CC BY-SA 4.0
2022-09-26T11:15:33.170Z
Hello Tom, welcome to 3DPrinting.SE! Please know we all were new to this once! In order to troubleshoot your issue it is best that we require some more information. The discussion of cold extrusion should be seen separately from the problem, so please make a photo of the 1" high print so that we can look at it for clues. Also remember to always pull the plug when you are (dis)connecting or fiddling with cables, you can destroy stepper driver when puling the cables while live. It is only advised to turn off `PREVENT_COLD_EXTRUSION` when you have removed the nozzle.
0scar
CC BY-SA 4.0
2022-09-26T14:36:41.350Z
It was not a I" high print Oscar, just a 1" length of the first layer of a Stripes Auto bed levelling test. I have now replaced the nozzle, the PLA Filament,that I am using for the the test. and the Bowden with a Capricorn as I need to print with ABS. The problem now is that Extruder Stepper Motor now tries to move but makes a clunking sound and stops. It is free to move Manually with no resistance. As I am a total novice with both computers and 3D printing, I am still trying to work out how to follow towe's advice to turn off Prevent-Cold-Extrusion.
Tom
CC BY-SA 4.0
2022-09-26T15:09:06.977Z
Thanks for the explanation of 1" length instead of height! P.S. if you are a novice, please do not try ABS, use PETG as an alternative, ABS shouldn't be the material to use as it is far more challenging than PLA or PETG. Do not pursue the advice to prevent cold extrusion unless you take the Bowden tube off of the hot end or remove the nozzle (and the filament can freely move through the hot end).
0scar
CC BY-SA 4.0
2022-09-26T15:45:34.970Z
Thanks Oscar, the main reason for following the advice is the HOPE that it will release the the "stop"  that was put on the Extruder motor by that function. I would have assumed that that would have happened when the printer was shut down and power was removed but it has not. Then again, maybe the motor/board has been fried!!
Tom
<creality-ender-3>
I'm new to 3D Printing and I've have just assembled a new Ender3 V2 with a CR Touch bed leveller. The extruder motor is not working
Tom
# I'm new to 3D Printing and I've have just assembled a new Ender3 V2 with a CR Touch bed leveller. The extruder motor is not working

(Asked by: username_0 on 2022-09-25)

Due to a mains power failure, I was unable to finish a "Thingiverse Stripes" auto bed levelling test on my new Ender 3 v2. When power returned several hours later and I tried to resume the Test, I discovered that the Bowden tube and nozzle were blocked.

I replaced the Bowden tube and nozzle but now found that after the first inch of the print layer the filament stopped, and the extruder stepper motor was not working. I checked that I could operate the extruder with the manual wheel to prove that there was no blockage and it worked ok. I also checked the extruder stepper motor in the "Move" mode; It would not turn in either direction. I think it tried to move but stopped instantly.

**Tags:** creality-ender-3

> **Comments:**
> **username_1**: Check whether all the cables are properly attached to the pins in the connector. Also, was the hotend heated while trying to do this? Some firmwares leave the pointless "safety feature" active to prevent extruder motion if the hot end is cold.  
> **username_0**: I checked that all the cable connections were good. However, I was following a youtube video instructions and I'm now pretty sure that the hotend was COLD when I restarted the print after the power failure and that is what caused the blockage. I have already seen your message about the Marlin "Pointless safety feature" but, as an old (81) novice, I have  no idea how to follow your suggestion. I would really appreciate some guidance please? Tom.  
> **username_1**: The feature is hard-coded into the firmware - to change it permanently, you'd have to compile a new one. It's also usually not an issue, but can be frustrating for beginners who don't know about it and wonder why their extruder won't move. In current Marlin, it's called `PREVENT_COLD_EXTRUSION` in the configuration.h file, which may be commented out to disable it. There's also a g-code to disable it semi-permanently: Sending `M302 P1` will disable the check, `M500` lets you save that change if saving settings in the EEPROM is enabled in your firmware.  
> **username_0**: Thank You username_1, as I understand what you suggest, the fix, "send M302" and "M500" must be done in Marlin and not in Cura. I wil now try to find out how to do that. Thanks again. Tom  
> **username_1**: That fix, sending `M302 P1` (the `P1` is important) and then `M500` can be done in any program that can communicate directly with the printer. I used to use "Pronterface" for that. You could also put those commands in a normal text file with the file ending ".gcode" and run that from an SD card.  Also, note that there's no immediate need to disable that feature, as long as you remember about it before wondering why the extruder might not work.  
> **username_2**: Hello Tom, welcome to 3DPrinting.SE! Please know we all were new to this once! In order to troubleshoot your issue it is best that we require some more information. The discussion of cold extrusion should be seen separately from the problem, so please make a photo of the 1" high print so that we can look at it for clues. Also remember to always pull the plug when you are (dis)connecting or fiddling with cables, you can destroy stepper driver when puling the cables while live. It is only advised to turn off `PREVENT_COLD_EXTRUSION` when you have removed the nozzle.  
> **username_0**: It was not a I" high print Oscar, just a 1" length of the first layer of a Stripes Auto bed levelling test. I have now replaced the nozzle, the PLA Filament,that I am using for the the test. and the Bowden with a Capricorn as I need to print with ABS. The problem now is that Extruder Stepper Motor now tries to move but makes a clunking sound and stops. It is free to move Manually with no resistance. As I am a total novice with both computers and 3D printing, I am still trying to work out how to follow username_1's advice to turn off Prevent-Cold-Extrusion.  
> **username_2**: Thanks for the explanation of 1" length instead of height! P.S. if you are a novice, please do not try ABS, use PETG as an alternative, ABS shouldn't be the material to use as it is far more challenging than PLA or PETG. Do not pursue the advice to prevent cold extrusion unless you take the Bowden tube off of the hot end or remove the nozzle (and the filament can freely move through the hot end).  
> **username_0**: Thanks Oscar, the main reason for following the advice is the HOPE that it will release the the "stop"  that was put on the Extruder motor by that function. I would have assumed that that would have happened when the printer was shut down and power was removed but it has not. Then again, maybe the motor/board has been fried!!  

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## 0 answers

