• Clean the contacts on the Waste toner unit.
• Clean the contacts inside the printer where the Waste toner unit is to be installed.
• Re-install the Waste toner unit.
• If the problem persists, contact Brother directly as there may be a fault with the machine.

• If the print quality is poor, remove the toner cartridge from the printer and gently rock it side to side.
• This movement helps distribute the toner evenly within the cartridge.
• After rocking the cartridge 5–6 times, reinsert it and print a test page.
• If the issue persists, check the life of maintenance items in case they need replacing.

If you have replaced your drum unit, you may need to calibrate the printer to ensure the best performance. Please follow the below instructions to complete the calibration:

If the printouts have marks on the page in a repeating pattern, remove the drum from the printer.

Using a lint-free cloth, gently clean the drum surface, taking care not to touch the surface with your fingers.