Printer settings lost?

I’ve had my CR10S4 for some time now and last year I upgraded the MB, installed new drivers, direct drive, improved bed heating etc. I learned how to use Marlin and Pronterface. I got everything working and my prints were really nice. A few days ago I decided to clean-up my wiring and installed chain-links for the X and Z wiring which necessitated dismantling the gantry. Anyway, the improvements were all done, basically rerouting the wiring. NO components were replaced. When I turned the printer ‘on’ and ‘homed’ the hotend it immediately traveled to the right until it couldn’t go further and of course jammed the stepper. All my ‘homing’ is screwed up? Why has this happened? I reinstalled Marlin with the same settings I used the last time I did any changes to no avail. Manual directional travels are correct except when ‘homing’ it all seems reversed? Why would these have changed? How do I fix it? I’m at a loss for what happened and how to correct it. I appreciate any help you may offer. Thank you in advance.

I had a similar issue. I think it is a main board. How or why I don’t know. In my case a new board solved all the issues and as it was flashed with the same exact firmware it seems for my case to be the likely culprit.

I didn’t exactly prove it completely so it is a best guess.

Thanks for your feedback kitedemon. I since hooked up my laptop and opened Pronterface and moved the nozzle to the front left side of the bed (steppers ‘off’) and saved that position to the eeprom. Turned off the printer then manually moved the nozzle to around the center of the bed. Powered on the printer and when I ‘homed’ the printer the gantry (Z) started moving up. I stopped it after 100mm. Weird or what? I also noticed that when moving nozzle towards either the X or Y ‘home’ position the gantry (Z) started moving down at the same time? Moving the X or Y away from the ‘home’ position and the gantry moves ‘up’ at the same time? You suggested the MB could be fried. Gee, I just installed the board (BTT SKR v1.4 turbo) last year and it performed flawlessly. Do you still think it’s the board? Telling ya, how my printer is performing now is so frustrating as it was running so well. I wonder if I may have caused damage/short to the MB with a static spark while playing with my connections (power unplugged) on the MB?

I don’t really know. mne was a mystery. It started months before where it would home to the left side corner, or try to. I checked all the settings re built the slicer profile reloaded the firmware. Randomly it did the same. I started ignoring it. Then it started to have issues of temp probes as well. I replaced all the thermoresistors and then the whole bed. It randomly did the same temp faults homing issues. New firmware again, cables , and the variety of faults continued. I replaced the board and all the phantoms are gone at least for the moment. I did nothing in between. I can’t say what your issue is. It started to sound similar so my shot in the dark guess is the board.

Its a guess.

I much appreciate your feedback. I rechecked all my connections, reloaded Marlin after checking all the settings which haven’t changed since my last working update. All axis move correctly except when I ask it to ‘home’, then it’s all screwed up. I ordered an exact replacement from Biqu since 3D PC doesn’t carry it any longer. It’ll be weeks before I can confirm the MB being at fault, fingers crossed. Thanks again for your help and have a super day!

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Thought I’d provide a follow-up to my issue. So I finally received my replacement SKR1.4Turbo motherboard and to make a long story short, got it working. So my printer seems okay even though while going through all this the Marlin version had changed and I used a ‘config’ which had to be cleaned up because options were ‘active’ which I don’t use like a “chamber”. Marlin is great but ‘a PITA’ to use, it could be much more ‘user friendly’. Anyway, one question which puzzles me is ‘why’ did my board fail in the first place? The day I worked on it wasn’t dry nor generating any static, HOWEVER, I got caught a couple of times with the build plate suddenly moving backward after tilting the printer up in order to access my MB located under it. So the question is: can the build plate sliding back uncontrolled, into the endstop a couple of times generate enough energy via the affected (in this case the ‘Y’ axis stepper motor) to damage the MB?

I suppose it could.

Any electric motor is also an electric generator when it free-wheels. The strength of the electric current created is related to the rate of change in the magnetic field, which means the faster the motor is freewheeling, the more electricity it’s generating. From your description, it sounds like the build plate slid back pretty fast, which would have been a relatively large spike of electricity. All of that had to go somewhere, and even if the spike made it all the way back to your mains, it would have passed through the motherboard on its way there.

I certainly don’t know enough about the specs of all the components involved to say for sure, but it seems like a reasonable guess at the cause.

I agree with you. I was watching the Teaching Tech video 3 ways to add a dual Z axis - Including G34 auto Z levelling - YouTube. At the 9min mark he states, “I unplug the Z stepper motor to prevent damage to the motherboard”, then, he starts to manually moving the Z leadscrews to position his gantry!! At 9:05 a statement is posted on his video again stating, “only perform fast manual movements with the stepper motor(s) unplugged to protect the motherboard”. My suspicions grew when I made the following observation. With the printer is UNPLUGGED from the wall, all stepper harnesses connected, I was turning a Z stepper by hand and the opposite Z stepper ALSO TURNED!!?? I tried the other way around and observed the same thing. If you turn a stepper SLOWLY no problem but turn it a little faster and bingo the opposite stepper turns even though the power to the printer is UNPLUGGED! Note: Both Z steppers are connected to the same harness in series. So I have a strong suspicion that the sudden aggressive movement of the build plate slamming into the endstop when tilted back several times damaged my MB. Why am I making a big deal out of this? So others don’t experience unnecessary damage to their MB while working with steppers. Now I unplug all my steppers when working on my printer. I also place a spring clip to pinch my Y belt so now my build-plate stays put should I have to tilt my printer up to access the MB.

What kind of motherboard/drivers do you have? Along with that, what kind of Z axis harness do you have with the wiring connected in series?

The back EMF of moving the steppers in a normal should not be sufficient to kill any decent electronics. If you have two Z axis stepper motors, they should only be wired in parallel.

If you go through the equations (and I can provide you with a spreadsheet I got from Trinamic), unless you are literally moving things at supersonic speed, you shouldn’t see any induced voltages greater than 10V.

I have never unplugged any steppers when servicing my printers and I regularly move things out of the way and let the X axis gantry and Y axis bed flop around without any worry that any of the electronics gets damaged. This has been in multiple printers.

I installed a BTT SKR 1.4 Turbo with matching TMC2209 drivers. My CR10S4 printer came with dual Z steppers and each harness joined into one harness which plugged into an MKS motherboard. I used the same harness and connection method on my new SKR 1.4T. I couldn’t check the actual connections of the harnesses without removing heatshrink and didn’t want to do that. I ‘guessed’ they were in series but from what you say they’re probably in ‘parallel’. I disagree with your opinion that under certain circumstances it’s okay to move stepper motors while they are connected to the MB. I disagree, and will side with caution. Thanks for your feedback!