I have an issue with the 393 Motors. Sometimes they work and other times they don't. Does anyone know if this is feature of the the batteries not being charged enough? There is no way to tell if they are really fully charged with only a red and green indication on the VEX "Smart" charger.
Thanks!

There are two internal fuses. One for ports 1-5 and another for ports 6-10. It is possible you are tripping these fuses. They reset automatically over time. Move your motor ports so that half the heavy load is on each fuse. If this does not resolve it completely you may need to reduce the current by changing the speed or gear ratio.