Haywire X axis

[Armatus]

I had to return the Rambo board on my Rostock Max V2 last week as there was something wrong with it that made the card reader not register. When I received the new one yesterday and plugged it into the machine, everything worked great, the extruder and bed heated up, the axis all homed correctly, and it read an SD card just fine.

Then later I put it all into the machine and closed it up, and my X axis started going crazy. When homing the machine it sometimes seems to be inverted, and sometimes it moves in the correct direction but all the motors make a terrible grinding noise even though there's nothing in the way. I've tried reversing the axis direction in the firmware, which didn't change anything. I've reflashed the firmware and eeprom a few times with no change. I've unplugged and replugged all the axis connections with no change and no visible damage to anything. I can't see anything that's wrong on the board. What's really weird is I had it all together and it homed just fine when I tested it the first time, then later when I put the board into the machine and closed it up everything went wrong. I'm at a loss.



Specifically it's doing one of two things now when the homing command is given, and it seems to switch back and forth between them;
1. The Y and Z axis start moving up towards the endstops but the X axis starts moving down. Y and Z touch their endstops and stop moving, while X keeps going towards the bed, so I have to turn off the machine.

2. All axis are moving in the correct direction when the homing command is given, they touch their respective end stop switches, move down a bit, then move back up to touch them again but they don't stop once they touch them the second time and all three motors just start grinding as they try to keep moving up past the limit switch, so I have to turn the machine off. I've checked that all the limit switches are plugged into the correct axis and that they all register in the terminal to be working.

I'm really hoping there's maybe something wrong with my X stepper and it's not a board issue? What else could it be?

[geneb]

Make sure the X, Y, and Z motors are plugged into the proper locations on the RAMBo. It sounds like you've got one or more swapped.

g.

[Armatus]

They're all where they're supposed to be, I've triple checked all my connections.

[Polygonhell]

if they are making noises as if they are jittering, you have a bad connection somewhere in the motor wiring.
Unfortunately it's often hard to determine what the issue in these cases, because often when you check with a meter, the wiring appears good.
The connector is most likely to be the culprit, you can try moving the wiring near the connector when it's homing.
If you have any inline connectors on the motor leads that would be the second place I'd check.
I should warn you, you can damage the RAMBO board this way, but it's often hard to determine where the wiring is bad without the motors connected.
The other option is insufficient cooling and too much current on the drivers, but that wouldn't explain running in the wrong direction.