Please look, for if some emergency Stop is activated???? this will block the RUN of motor.
2) if everything is o.k, please measure the Input to the DC Drive, electronic board according with his schematic diagrams, and if there are then look for the Output in the Dc Drive Board, if there are and the MOTOR not RUN, is indicative the Motor is defective, by the contrary side, if there are NOT output in the DC Drive Board, if indicative the Dc drive board is faulty.
However , look for some connector, loose, or broken, or dirty, or oil, and tight and clean very well.