X, Y, Z motors not responding when testing

None of my motors are responding when I perform a test run during the setup, Power is coming into the g-shield but no power is going out to the motors.

Power supply on/ working? The shield is powered via usb, motors powered from the power supply. Maybe it’s bad, do you have a multimeter?

check to see if the system isn’t in alarm mode or locked.
When you first power it up it will be locked until you issue a unlock or homing command.

How do I issue a unlock or homing command?