Dead extruder stepper on my ender 3 pro.

[Azurl]

Hi,I ran into a problem a few weeks ago, my extruder would stop pushing filament mid print, the steppper motor just stopped.turns out the heatsink on the stepper controller was knocked off by bad cable management. I'm using a SKR v1.4 turbo from BigTreeTech with TMC2130 stepper drivers for each axes and Extruder. I reattached the heatsink but it seemed to have died, everytime it tries to move the extruder now it jerks a little bit then stops responding. I have since replaced both stepper controller and motor, but it still does the jerk then stop, don't know if jerk is the right word, it doesn't make the full motion when trying to load or unload 5mm of filament, it vibrates a little like it tries to move the motor but doesn't have enough strength.I feel my only other option now would be to replace the motherboard. but does it seem likely the motherboard has been damaged?

[AutoWiz]

Are your steppers running in standalone mode? And if so did you adjust the pot on the stepper and set the forward current to a happy place? It sounds like the vref might be a bit low. Or there might be a problem with the wires from the driver to the stepper or their connections. Also cable management is not a hard thing to get a hold of. Sometimes it means identifying and hunting down the right connector or pigtail. A lot of times it means using a soldering iron and making custom length harnesses. And it is always better if you design the mainboard tray with cable management in mind. My SKR PRO here has a stepper in every socket and yet not a single wire draped over the mainboard..

[Azurl]

Are your steppers running in standalone mode? And if so did you adjust the pot on the stepper and set the forward current to a happy place? It sounds like the vref might be a bit low. Or there might be a problem with the wires from the driver to the stepper or their connections. Also cable management is not a hard thing to get a hold of. Sometimes it means identifying and hunting down the right connector or pigtail. A lot of times it means using a soldering iron and making custom length harnesses. And it is always better if you design the mainboard tray with cable management in mind. My SKR PRO here has a stepper in every socket and yet not a single wire draped over the mainboard..

That is really beautiful cable management. I've been considering getting ribbon cables that I can cut to length and replacing the stock ones. but that's a later project, I tried increasing the forward current with no effect, then I increased the vref from 0.960 volt to 1.1 volt. no effect either, but these values have not been changed for over a year of operation, and it stopped working after I replaced the heatsink on the stepper controller, it was working without the heatsink, but stalled after a few minutes of operation. now I've tried 3 different stepper motors and 2 different stepper controllers. when I try to load or unload filament to make the extruder stepper move, it makes that jerk sound, in some cases I can try several times, but eventually it stops responding at all, and a led on the mainboard starts flashing really fast, it's the LED next to the Q3 transistor. can the mainboard have been damaged when I fiddled with the stepper controller?

Edit: I think they are in standalone mode, I didn't fiddle with any particular mode settings, unless I have it wrong it's either standalone or closed loop? I think they are in SPI mode.

[AutoWiz]

First off the stepper driver that had the heatsink fall off it is very likely dead. You said so yourself by claiming that half way through a print it stopped working. This was you explaining to the group that you overheated that stepper driver to the point of failure. And no putting a heatsink back on a burnt driver doesn't magically put the smoke back in. Once you let the smoke out it is out. you know? This damage should be limited to the stepper driver UNLESS you reconnected the heatsink in such a way that you shorted pins on that stepper driver. If you tried to put that heatsink on while things were plugged in and powered on and or if the aluminum heatsink were allowed to touch rows of pins on the stepper driver then yes you might need a new mainboard. One nice thing we have going for us with the SKR boards is 5 driver sockets. You should only need 4. X, Y, Z, and E. If one of your extruder sockets is now dead then perhaps you should be using the empty and available stepper motor socket?

[Azurl]

I don't think it burned out as it kept printing in the beginning and stopping after a few millimeters of print. and I took the stepper driver out of its socket when reattaching the heatsink as I needed to reapply heatsink adhesive.

is there a way to pull the firmware from the mainboard to put in a new one? I've reinstalled my windows since I made the changes and compiled the firmware, I can of course redo it all, but copying from this mainboard onto new one would save so much time.

[AutoWiz]

Well in the future you should save your important files in more than 1 place. Even on a spare usb thumbstick or sd card. I enjoy setting up Marlin and you should, too. I say this because there are always new versions of Marlin coming out and if you are comfortable with setting it up then you will likely always run the latest version instead of whatever you were able to get going that one time. Currently Marlin is up to 2.0.7.2 But before you change the mainboard why not use the other extruder stepper socket?

[Azurl]

Well in the future you should save your important files in more than 1 place. Even on a spare usb thumbstick or sd card. I enjoy setting up Marlin and you should, too. I say this because there are always new versions of Marlin coming out and if you are comfortable with setting it up then you will likely always run the latest version instead of whatever you were able to get going that one time. Currently Marlin is up to 2.0.7.2 But before you change the mainboard why not use the other extruder stepper socket?

do I need to make any firmware changes to do that? or can I select which extruder to be the main one in the menu?

[AutoWiz]

Oh you will need to make changes to your firmware. But you can save the time and money of replacing the mainboard. Also have you plugged the extruder into a different axis like x or y and commanded movement to verify the integrity of your wiring??

[Axl_Myk]

I thought it was spelled Merlin.

[AutoWiz]

But there's a picture of a big fish in the logo..