How to replace a toner cartridge or drum unit in a brother laser printer
How to Replace a Toner Cartridge or Drum Unit in a Brother Laser Printer
Brother laser printers usually use two separate consumables: a toner cartridge and a drum unit. The toner fits into the drum, and the two parts slide into the printer together. This guide shows how to replace each part safely and what to check if the printer still shows a warning.
Toner cartridge vs drum unit — what is the difference?
Brother printers often use a toner cartridge and a drum unit as two separate parts. Replacing the wrong part can leave the original warning message on the printer.
Contains the toner powder
The toner cartridge contains the fine powder used to create the print on the page. It usually needs replacing more often than the drum unit.
Transfers toner to paper
The drum unit works with the toner cartridge to transfer the toner powder onto the paper. The drum normally lasts for several toner cartridges.
Before fitting a new toner or drum
A few simple checks can prevent leaks, recognition errors and unnecessary returns.
Do this first
- Keep the printer switched on unless your model’s reset instructions say otherwise.
- Open the front cover fully before removing the toner and drum assembly.
- Place the old assembly on disposable paper in case loose toner escapes.
- Remove all orange clips, covers, seals and protective packaging from the new cartridge.
- Handle toner carefully and avoid touching the drum surface.
Avoid this
- Do not force the toner cartridge into the drum unit.
- Do not touch the shiny drum roller surface.
- Do not reset the drum counter unless you have replaced the drum unit.
- Do not throw the empty cartridge in general waste if it can be recycled.
- Do not continue printing if loose toner is leaking heavily inside the printer.
How to replace a Brother toner cartridge
These steps apply to many Brother mono laser printers where the toner cartridge clips into a separate drum unit. The exact shape may vary, but the process is usually very similar.
Open the front cover
Make sure the printer is stable and switched on. Open the front cover so you can access the toner and drum assembly.
The toner and drum normally come out together as one combined unit.
Remove the toner and drum assembly
Hold the handle and gently pull the toner and drum assembly straight out of the printer.
Place it on a sheet of disposable paper in case a small amount of toner powder escapes.
Release the old toner from the drum
Push down the green lock lever on the drum unit and lift the toner cartridge out.
Keep the drum unit because you will reuse it unless you are replacing the drum as well.
Prepare and fit the new toner
Unbox the new toner cartridge and remove the orange protective cover, seals and any packing material.
Slide the toner cartridge firmly into the drum unit until it clicks into place.
Clean the corona wire
Slide the green tab on the drum unit from side to side several times.
Return the tab to its home position afterwards. If the tab is not returned correctly, prints may show a vertical stripe.
Reinstall the assembly
Push the complete toner and drum assembly back into the printer until it is seated properly.
Close the front cover and allow the printer to initialise. If a warning remains, you may need to reset the toner counter for your model.
How to replace a Brother drum unit
Replacing a drum is similar to replacing toner, but you reuse the toner cartridge by moving it from the old drum into the new drum unit. Only reset the drum counter after fitting a new drum.
Drum replacement process
- Make sure the printer is switched on.
- Open the front cover.
- Remove the toner cartridge and drum unit assembly.
- Press the green lock lever and remove the toner cartridge from the old drum.
- Unbox the new drum unit.
- Fit the toner cartridge into the new drum until it clicks into place.
- Clean the corona wire using the green tab.
- Install the full assembly back into the printer.
- Reset the drum counter for your printer model.
Important drum notes
- The drum unit does not contain toner powder.
- The toner cartridge must be transferred into the new drum unit.
- Do not touch the drum roller surface.
- The drum counter should only be reset after installing a new drum.
- If print quality is poor after replacement, check the corona-wire tab has been returned to its home position.
Example resets after replacement
Reset methods vary by Brother model. These are examples for common Brother printer families. Use the exact reset guide for your model if you are unsure.
DCP-L2520DW / DCP-L2540DN / HL-L2340DW / MFC-L2700DN
- Open the front cover.
- Press and hold OK for around 2 seconds.
- Press the up arrow or 1 to reset the drum counter.
- Close the front cover.
Example toner counter reset
- Open the front cover and leave it open.
- Turn the printer off.
- Hold Go while turning the printer on.
- Release Go after around 3 seconds.
- Press Go 9 times.
- Press Go 5 times.
- Close the cover.
Use our Brother reset guide
Brother reset sequences can vary by printer model and toner capacity. Use our model-based reset guide before trying a reset.
Official Brother support videos and guides
These official Brother support pages are useful if you prefer to follow a video or manufacturer diagram.
Replace the toner cartridge
Official Brother video guidance for replacing the toner cartridge on related Brother laser printer models.
Replace the drum unit
Official Brother drum replacement guidance, including removing the toner from the old drum and resetting the drum counter.
TN243 / TN247 counter reset
If you have a Brother colour laser printer using TN243 or TN247 toner cartridges, this guide shows how to reset the correct colour and capacity.
Troubleshooting after replacing toner or drum
If the printer still shows an error after replacement, the issue is often seating, packaging, the wrong counter, or a reset sequence that has not been completed.
Make sure the toner cartridge is correctly clipped into the drum unit and all packaging has been removed. Some models may need the toner counter resetting.
This usually relates to the drum unit, not the toner cartridge. If you have fitted a new drum, you may need to reset the drum counter.
Clean the corona wire by sliding the green tab from side to side, then make sure the tab is returned to its home position.
Check you have the correct toner cartridge for the drum unit and printer model. Do not force it, as this may damage the cartridge or drum.
Avoid using hot water. Carefully wipe loose toner away and wash hands or clothing with cold water if toner powder gets on them.
Check the exact message on the printer display. Toner messages normally refer to the toner cartridge, while drum messages refer to the drum unit or drum counter.
Need help replacing a Brother toner or drum?
If the cartridge will not fit, the printer still shows an error, or you are unsure whether you need a toner, drum or counter reset, our customer service team can help.