Y-motor doesn't run anymore

Yesterday afternoon, everything worked well. I adjusted the position of the tool slots when the Y axis was suddenly blocked:
when I ask for movement on the Y axis, nothing moves. (The X and Z axes run normaly)
When I disable the Y encoder, the farmbot indicates motion, but the motor does not run.
On the arduino board, I reversed the Y-Axis and Z-Axis plugs, and in this case, the Y motor obeys a command on Z, but the Z motor does not respond to a command on Y.
Thanks for your help !

So you plugged the Z motor into the Y-Axis connector of the arduino board and it did not move? So there is no output from the Y-axis on the arduino board?

Try to change the Stepper driver with the Z-axis to check if the driver is faulty.

OK, I’ll try this tomorrow, thank’s !
The stepper-driver can be removed simply by pulling it ? (It was mounted on delivery)

Yes, Just pull it off and plug it in the same orientation.

I switched the Y-motor stepper driver and the aux-motor stepper driver, and it works again !
Thank you so much !