Printer refuses to print. "Replace toner" message.
Operating system does appear to submit to print queue. (Windows 10)
Printer toner indicator says Black is almost full (recently changed as I print mainly b/w), Cyan & Magenta are low, Yellow is empty and the one it complains about when trying to print.
I've continued messing with it for the last hour and even putting the printer into "black and white" mode, and changing the printer options in the OS to "Mono" it still refuses to print. Brothers own help page says it works [0], but I've followed these and it still doesn't print.
I've tried resetting the printer, updating the firmware and drivers, rebooting both printer and computer.
The yellow toner is needed to print the yellow steganographic dot pattern containing the printer serial number. My guess is that for Brother to comply with its agreement with the US Secret Service, the printer has to have yellow toner to print anything at all.
Also the wording in the Brother tech support article you linked to tells us how to print *using* only black toner, it does not say that this works when the color cartridges are empty. Sneaky bastiches!
Does the printer refuse to print, or does the operating system printing subsystem refuse to print?
What is your operating system?
Have you given Brother support an opportunity to respond?