Is the amount remaining in toner cartridge running low?
Check how much the amount remaining in toner cartridges is left, and replace the toner cartridges as necessary. Replacing the Toner Cartridge
Regardless of the displayed toner level, the toner cartridge may have reached the end of its lifetime due to the machine's environmental conditions and the deteriorated materials in the cartridge. Replace the toner cartridge. Replacing the Toner Cartridge