Replacing the BJ Cartridge
The BJ cartridge contains ink and a print head. Replace it if any one of
the following conditions is met:
When the cartridge has been used for over one year.
When the print is not clear, or has missing dots even after head
cleaning has been done over five times.
Make sure the printer is offline.
Open the top cover, then the paper cover.
Unlock the BJ cartridge.