Refill instruction Brother LC-980, 985, 1100 XXl refillable cartridges

Plug the needle into the syringe. Draw up the ink with the refill syringe. These refillable cartridge can hold so much ink, that you have to draw up the ink a few times. Take the cartridge (as shown in pict.1) in your hand and pull out the closing plug (as schown in picture 2).

Before you put the cartridge back into the printer, you have to remove the aeration plug (pict. 4). Now, please apply the air filter (pict. 5). This equalizes the pressure inside the cartridge during the printing process.

As the cartridges stick out of the cartridge case, you won´t be able to close the cover of the cartridge chamber. The printer refuses its service, it signalises, that the cover is open. For that reason, there is a plastic flank included in delivery (pict. 6). This simulates a closed cartridge case.  
This flank has to be attached to the cartridge which is straight under the small opening, that contains the sensor which sends the signal "cartridge case closed" to the printer. There is just this one small opening. Most of the times, the plastic flank has to be stucked on the provided connector on the magenta cartridge (pict. 7).
It also may be that the flank has to be put onto another cartridge.
When you have apllied the plastic flank correctly, you can start printing again.