X Axis not moving - judders and makes noise

I’ve just finished building my X-Carve (Fully loaded 2015).

Setup ran okay, I’ve installed the drivers and the Y and Z axis are fine. The X axis doesn’t move.
I thought I may have tightened too much, I slackened all of the V wheels off and the belt a bit, nothing. It moves really easily with the power off.

It judders on the spot whichever way you try to move it. I have 1 blue and 3 green lights.
Any ideas?

Thanks!

From the other posts I’ve read, loose/broken wire would be my guess.

Can you post a picture of your wiring on the back of he gantry?

Check pulley that it is secured properly / isnt slipping?
Stepper driver for that axis set too low?

I could kiss you all!
Thank you! I looked at all the wires I could see, all looked fine.
Took the top off the G-shield, all set the same.

Then noticed that one wire in the g-shield was slightly loose. Tightened him, and all working well!

Next step! Thanks again!