That error message is not listed even by Brother's own information on that model of printer.
This indicates either a severe and rare error - bad news, in short - or else, just perhaps, something just plain unusual.
Try following these illustrated instructions, step-by-step, for removing and putting back in, your toner cartridge of the Cyan color.
(Make sure the Cyan cartridge is actually in the Cyan slot, of course! that slight mistake might produce an unusual error.)
Also, while that cartridge is out of the machine, look in the Cyan cartridge and drum's slot, and make sure there isn't any toner spillage onto any metallic contact surfaces. IF there were such spilling of toner, a special cleaning-out, following certain procedures, would have to be done... let me know, if so, so that I may instruct you.
Let me know how it goes, please.