No movement on Z and X axis

I am trying to get started with my SO3 XXL. Everything is assembled and I am trying to job the machine. I had started out in CM v4, but rolled back to v3 since I was having problems. Here is what happens:

I turn on Carbide Motion and the router connects without issue.
I hit the jog button and then click to begin homing.
The hexagon comes up with the message “Homing Machine”
Nothing happens for about 15 seconds, and then the Move Cutter screen comes up (the machine does not move nor does it home).
I click either the “Z+” or the “Z-“ button and a tapping sound comes from the area of the Z and X motors. I assume it is probably from the Z motor since that is the button I pressed, but I cannot tell. This tapping sounds goes on for about 10 seconds and then stops. The machine does not move. If I click the Z+ or Z- buttons again, then nothing happens. If I press any of the X or Y buttons the machine will move in those directions respectively.

If I go to the MDI tab, I can enter commands like g0x10 or g0y20 and the machine will move, by g0z10 doesn’t work.
If I enter $h, I get the following error after a few seconds “GRBL Error: 9” and the machine does not move.

What I have tried:
Loosen and retighten both set screws on all off the pulleys on the machine.
Loosen the V-wheels all the way.
Loose V-wheels and loose Z Belt
Loose V-wheels and tight Z belt
Moderately tight v-wheels and loose Z belt
Moderatel tight v-wheels and moderately tight Z belt.
Confirming all of the motor and limit switch wires are plugged in to the correct place.
Unplugging, wiggling, replugging, and wiggling all of the wires.
I have unplugged the limit switches and the machine still moves on the x and y paths but not the z path.

Is there anything else that you would recommend?

Update: I removed the homing to simplify the process. To start with I was able to jog the machine on the X and Y axes, but not the Z. I unplugged and replugged all the motors, and now the X axis will not work either. I have unplugged, replugged, wiggled the cord and adapters, shut down the router, shut down CM, and rebooted my computer multiple times in multiple different sequences and still neither the X axis nor the Z axis will respond.

Thanks for your help.

Ouch.

Please check the wiring and contact support@carbide3d.com — you’ve either got a bad wiring extension or (more likely) a wiring extension which then blew out at least one stepper driver.

If you have a multimeter, please use it to evaluate your wiring for continuity — let us know what you’ve done and we’ll work it out with you.