I have a SAJO knee mill with Centroid M400 controls. The servos are SEM DC, brushed units. I had a problem with the encoder on the y-axis. I ordered another and installed it. After the installation, the machine will not home. It starts attempting to home on the z-axis, which now says full power without motion, in other words it has lost position indication on that axis. It will not move the x, y, or z axis with the jog commands. Any ideas?