Your printer will work smoothly only if it has enough ink and toner in the cartridges. Let’s see how to replace toner Brotherprinter process. The printer should be turned on while removing the cover. Then, hold the green handle of the drum unit and pull it out until it stops. Unlock the toner cartridge by pushing it away. You will see the corona wires here, clean them gently. Now, remove the new toner from the cover. Then, insert it in the drum unit and pull it towards your till you hear the lock. The colors of the toner and as marked on the printer should match. Use the green handle to push it back and close the cover.