A Limit switch (or "Home switch"), is a normally closed switch, which means that when nothing is pushing on them they report being "on". If a wire is broken or a connector is disconnected, the controller will think that the machine is at the end of travel, and will bring the machine to a halt.
The image to the right shows the various kinds of switches we use, and the part numbers associated with them.
Troubleshooting
Note the gray wire coming out of the black housing at the back end of the motor in question. Where does it lead? If it leads to a white connector that is loose, you have found your problem. Reconnect the two white connectors. If the connector was indeed connected to its mate, try disconnecting it, so you can check the switch.
After disconnecting the connectors, use a multimeter set to test for continuity on the connector that does not lead into the motor housing. If the axis is not at the end of travel, you should find that the contacts are continuous. If there is no continuity, there is either a break in the wire, or the switch is damaged. If you can see a break in the wire, consider repairing it if possible. Otherwise, please contact Techno for further instruction.