Y Motors not responding (X and Z are fine)

Whilst setting up for a carve today I was going through the set up steps and found that the Y axis was having trouble moving and would stutter. I checked the wiring and found that one of the wires connecting to the G Shield had come loose. I turned everything off and reconnected the wire and now, nothing. No response at all.

I’ve been through various threads on the forum but have not found much specific to this issue. Through reading some of these threads I’ve completed various trouble shooting to test everything and have more or less come to the conclusion that there has been a short and I will need to get a new shield but figured I would post here before spending the money.

This is what I’ve tested/ observed so far:

-During start up all lights on the shield will usually light up. The Y axis now will not light during this cycle.
-The wiring is assumed to all be correct (as there was only one loose and have run this machine for months before now without issue) as when it is off and I manually move the Y axis the light will come on…
-I have moved the Y axis wiring to the X axis and the motors respond as normal.(no response from X wiring in the Y axis connections)

  • usually when turned on all of the axis’ will lock an cannot be moved manually. This no longer happens with the y axis and can still be moved by hand

Please if anyone has any suggestions of things i may have missed or other tests I can perform, I would greatly appreciate any input.


"[quote=“SeanGrey, post:1, topic:25938”]
I turned everything off and reconnected the wire and now, nothing. No response at all.

Does this mean that none of the axes work now, or that the Y axis doesn’t do anything anymore?

If X and Z still work, but Y doesn’t then I think you are correct. Your tests would indicate a failure of the Y axis driver chip.

If nothing works, then you should try to reseat the gShield on the Arduino and see if you caused it to come loose when you re-attached the Y wire.

Does the Arduino still respond to commands?

Hi Larry,
Yes, sorry. only the Y axis is not functioning. the x and z are perfectly fine.the rest of the arduino is responsive to all commands as well. I figured that would be the case and I would need to get another shield but I wanted to ask first just in case.


Swap the wires for the X and Y axis, and then try and jog the axis. If it follows the axis it’s a wiring/stepper issue, and if it follows the driver, it’s the driver. Of course they both may work, since you might not have reseated the wire correctly, maybe pinched the insulation instead of the wire. In which case swap back to normal and carve.