Brother HL 1650 - Manual (Page 150)

5-10
☛ ☛ ☛ ☛ 6.
Install the new Toner cartridge into the Drum unit until you hear it lock into
place. When the Toner cartridge is installed correctly, the Lock lever is lifted
automatically.
Fig. 5-6
!
Caution
Make sure you install the Toner cartridge correctly or it may separate from
the Drum unit when you pick up the Drum unit assembly.