Why does one or more of the robots joints refuse to work?

The Base, Shoulder and Elbow joints of the Robotek robot are fitted with a servo saver . The servo saver is a device that disengages when a robot joint is subject to an adverse force. The servo saver deliberately disengages to prevent damage to the servo motor. When the robot joint has been re-engaged, it will continue to operate as normal.

A document describing this and how to fix this is contained in the latest versions of the paperwork.