Brother MFC-8440 B - Manual (Page 171)

TROUBLESHOOTING AND ROUTINE MAINTENANCE 12 - 10
8
Push the lock lever down and take the toner cartridge out of the
drum unit assembly. Take out the jammed paper if there is any
inside the drum unit.
9
Put the drum unit assembly back in the MFC.
10
Put the paper tray in the MFC.
11
Close the front cover.