Another baffling y-stop problem.

Our collection of 3d printers at the local makerspace includes a Lulzbot Mini. It has been our most used and favorite printer, but we have run into a baffling problem. When the machine homes, the y-stop does not register and the motor continues to run. Here are the steps we have take so far:

  1. Replaced the wiring between the board and the end stop (twice - the last time with a cable made and tested by an electronics engineer).
  2. Replaced the board with a used refurbished one.
  3. Replaced the microswitch.

You can hear the switch click when it hits the stop and with a meter, can see that the switch activates.

Any suggestions about how to proceed?


If all you’ve listed above is true, then there is only one thing I can think of. Are you absolutely positive that when you rewired the board that you got your Y min and Y max connections correct? If you swapped those unintentionally you’d get the exact issue you’re having. I believe it’s possible to mix up any of the limit switch connections on the board.

I swapped my limit switched while doing a repair and it caused the same issue.

Anyways, just a guess. I’d go back and triple check those connections. Perhaps you should also pull each one and reseat it just to make sure it’s connected well.

After that, I’d be on the phone with lulzbot support.


YES. Do a M119 command to manually test all your limit switches by hand.