Well you should be able to measure around 5v and 0V on the DIR pins depending on which way the axis is moving. So X axis DIR pin will be high in one direction and low in the other.
THe pulse pins i imagine will be 0 or 5V when not moving then on a multi meter, it will effectively average the pulse levels, so it might be ~ 2.5V when moving. Or it might dance around when moving, it could depend on the meter exactly, but the point is you should see a difference in measurement between stopped and moving.
If that is a go then next step i would measure the power supply to the stepper drivers them selves. Probably it is 24 V DC on this machine, but look for the power supply it will say on it i would bet.