the service manual says the code means "Carriage Unconnection Error" - I'm not 100% sure, but my guess is the carriage that holds the cutter is disconnected from the print head.
Let me start by saying I'm not a tech and I'm not afraid to rip my own machine apart - whether or not it's a good idea I won't speculate on. I feel like I've gotten this error before. I would unplug the machine and remove the cover where the display face is and see if they are in fact disconnected from one another, if memory serves me correctly there is a magnet that holds them together - I would (and remember I'm not a tech) just push them back together gently if they were disconnected from one another.
I've had my machine (sp300v) for over 5 years now - and after I had error codes the first day I owned it, and realized I knew more about the machine than the tech that was sent out to "fix" my machine - I've just jumped in with both feet and never called a tech again. You can do what you want with this information, it may or may not be right, but it's what I would do if I got the same error. Good luck!
Gene