Z-axis not working

[mkeymont]

Hi Bertus,
FWIW, I originally got a clone board on Amazon, but have since replaced it with a real board, v3.51. I got it all assembled and all works except for the Z-axis. I’ve swapped the motor and the driver back and forth with the X-axis and all works when swapped. This seems to be a board issue, so I went back and touched up all of the solder pads, but no luck.

Troubleshooting steps:
Swap motors Z to X, X to Z: Z works, X doesn’t
Swap driver boards Z to X, X to Z: Z doesn’t work, X does (the problem stays with the physical Z-axis on the board regardless of which driver is where. This tells me that the driver boards are good. Since the Z-axis motor DOES move when being powered by the X-axis, I know that the motor and mechanical setup are good as well.)

Like I said, I originally had a clone board and it was working fine, so this started when I upgraded to the new board. The best clue that I have, I think, is that when I jog the Z-axis, the motor DOES “try” to move - I can feel a very brief “pulse” on the motor shaft when I send the command, but it doesn’t actually turn.

Thoughts? Maybe a bad capacitor??