Brother printers have a bad low toner count mechanism which prematurely tells the end user that the toners are low when they are not. The following steps will rest the toner count.
1. Open the front cover that gives you access to the toners.
2. Press and hold “Secure Print” and “Cancel” at the same time. You will see “K-TNR-STD” display on the screen.
3. Using the “+” and “-” buttons select the toner you want to reset.
4. Press the “Ok” button.
5. It will display “Ok?” and hit the “Ok” button again to reset the toner.
6. Close the lid.