Prusa i3 Stepper Motor Vibrating Buzzing Not Turning

Dear Prusa Community, I would really appreciate your help troubleshooting this issue as I've been stuck on it for days now.

Issue: I have the Prusa 2020 i3 Aluminum Kit and am using the Folger Tech Marlin Firmware with Repetier Host. My motor for the X axis is not turning and instead buzzes and vibrates noisily.

Troubleshooting done thus far:
-swapped wires/pins: if I plug the X motor into the Z or Y pins (the Z and Y stepper drivers) on the motherboard, it functions perfectly and the buzzing switches to whatever motor is currently plugged into the X stepper driver. In other words, I don't think the X motor itself is the problem.
-switched stepper drivers: I switched the stepper drivers of the X motor and Y motor. The Y stepper motor kept functioning normally, the X stepper motor continued to buzz and vibrate without turning. In other words, all of the stepper drivers themselves are in functioning order.
-adjusted potentiometer: I have adjusted the potentiometers on the stepper driver with a multimeter to various settings with no success. Only change is it buzzes less at lower power and more loudly at higher power, but the X motor still won't turn. So the issue is not one of insufficient power.

As a result I suspect one of the following issues:
1. the motherboard pins for the X stepper drivers are faulty. I think this may be the culprit as the first time I turned my prusa on, any stepper driver placed on the X pins would become overheated.
2. I am using the wrong speed/acceleration settings. My current settings are the defaults from the Marlin firmware on the Folger Tech google drive, but please let me know if anything here raises an eyebrow or is incorrect. I have included my Configuration.h code below.

// default settings 

#define DEFAULT_AXIS_STEPS_PER_UNIT   {80,80,3840,90}  // default steps per unit for ultimaker {78.7402,78.7402,200*8/3,760*1.1}920
#define DEFAULT_MAX_FEEDRATE          {250, 250, 2, 22}    // (mm/sec)    
#define DEFAULT_MAX_ACCELERATION      {1000,1000,5,1000}    // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for skeinforge 40+, for older versions raise them a lot.

#define DEFAULT_ACCELERATION          500    // X, Y, Z and E max acceleration in mm/s^2 for printing moves 
#define DEFAULT_RETRACT_ACCELERATION  500   // X, Y, Z and E max acceleration in mm/s^2 for r retracts

// Offset of the extruders (uncomment if using more than one and relying on firmware to position when changing).
// The offset has to be X=0, Y=0 for the extruder 0 hotend (default extruder).
// For the other hotends it is their distance from the extruder 0 hotend.
// #define EXTRUDER_OFFSET_X {0.0, 20.00} // (in mm) for each extruder, offset of the hotend on the X axis
// #define EXTRUDER_OFFSET_Y {0.0, 5.00}  // (in mm) for each extruder, offset of the hotend on the Y axis

// The speed change that does not require acceleration (i.e. the software might assume it can be done instanteneously)
#define DEFAULT_XYJERK                20.0    // (mm/sec)
#define DEFAULT_ZJERK                 0.4     // (mm/sec)
#define DEFAULT_EJERK                 5.0    // (mm/sec)

Thank you for your help,

Ben

I would follow your first conclusion. Bad solder contacts or solder bridges around the x-stepper driver pins.
Probably missing or bad microstepping jumpers?

Thank you so much or the fast response! The note about the bad jumpers was a good thought, but I just switched the jumpers that were under the X driver with those under the Z driver with no change. X stepper keeps buzzing. Z steppers functions perfectly.

I'll work on taking apart the Ramps 1.4 board so that I can double-check the soldering. It came ready-made in my Folger Tech kit, so I really don't know what state the soldering is in.

Thanks again for the advice! It's really helpful to have some guidance and support as I troubleshoot this issue.

Has your X axis ever worked or is this a start up situation? Can you take the belt off of the stepper motor and, when you tilt the machine, does the X head assembly slide from side to side easily?

---

Folger Tech 2020 i3 and FT-5 as well as modified JGAurora A5 with direct drive E3D/Titan. All running the BLTOUCH.
Great kits. Having fun and running the heck out of them.
Running Marlin 1.1.0 RC8 on the i3 and FT5. Custom firmware on A5.
Folger Tech Wiki board >[folgertech.wikia.com]

@tjnamtiw The X output pins have never worked (so yes, a startup issue). The X head assembly won't slide if tilted. With that said, the bearings on the X head assembly run pretty smoothly and will work fine as long as they are plugged into another set of output pins.

@o_lampe I decided not to take apart the ramps board in case that would void any "dead on arrival" warranty I have with Folger Tech. With that said, my friend is going to let me borrow his ramps board (same model and specifications) later this week and we're going to see if that fixes the issue.

Quote
benjaminlbarba
@tjnamtiw The X output pins have never worked (so yes, a startup issue). The X head assembly won't slide if tilted. With that said, the bearings on the X head assembly run pretty smoothly and will work fine as long as they are plugged into another set of output pins.
.

Without the belt being on the stepper motor, the extruder head assembly should EASILY slide from side to side. If it doesn't, your bearings are not aligned properly. Judging from my experience as well as other posters, the X axis carriage is not properly sized and the bearings don't fit easily OR AT ALL into the carriage properly. Most people must go in and carve or Dremel the openings to let the bearings fully seat. Once you are running AND PROPERLY CALIBRATED, you can print a new one out of PLA or PETG using the FT files. The bearings then snap right into place as they should.

---

Folger Tech 2020 i3 and FT-5 as well as modified JGAurora A5 with direct drive E3D/Titan. All running the BLTOUCH.
Great kits. Having fun and running the heck out of them.
Running Marlin 1.1.0 RC8 on the i3 and FT5. Custom firmware on A5.
Folger Tech Wiki board >[folgertech.wikia.com]

Yes that's good advice. I definitely plan on printing a few new parts - most notably, the carriage needs an upgrade as you mention.

However, at the moment my most pressing issue is the bad X output pins that are preventing any motor that are connected to them from turning/rotating as they should. For instance, the Y axis slides really well yet when connected to the X output pins, it just buzzes and vibrates. So the X output pin issue is unrelated to the misaligned carriage.

Quote
benjaminlbarba
Yes that's good advice. I definitely plan on printing a few new parts - most notably, the carriage needs an upgrade as you mention.

However, at the moment my most pressing issue is the bad X output pins that are preventing any motor that are connected to them from turning/rotating as they should. For instance, the Y axis slides really well yet when connected to the X output pins, it just buzzes and vibrates. So the X output pin issue is unrelated to the misaligned carriage.

I understand that and just threw it out as a caution. You are taking good steps by using your friend's electronics as a test.

---

Folger Tech 2020 i3 and FT-5 as well as modified JGAurora A5 with direct drive E3D/Titan. All running the BLTOUCH.
Great kits. Having fun and running the heck out of them.
Running Marlin 1.1.0 RC8 on the i3 and FT5. Custom firmware on A5.
Folger Tech Wiki board >[folgertech.wikia.com]

You can never have too many arduino/RAMPS boards at home

Just wanted to follow up with you guys and let you know that my issue is fixed. It was indeed the ramps board that was bad. As soon as I plugged in my friend's ramps board, all the axes rotated perfectly. Thank you for your advice and help troubleshooting this issue. I'm looking forward to being able to print soon!