Brother HL 3070CW - Manual (Page 126)

Routine Maintenance
116
5
d
Unpack the new drum unit and pull off the protective cover.
IMPORTANT
Wait to unpack a drum unit until immediately before you put it in the printer. Exposure to direct sunlight or
room light may damage the drum unit.
e
Put the toner cartridge firmly into the new drum unit until you hear it lock into place.
IMPORTANT
Make sure that you re-install the toner cartridge properly, or it may separate from the drum unit.