Brother HL 4150CDN - Manual (Page 110)

Routine Maintenance
104
5
i
Turn the green lock lever (1) clockwise to the lock position.
j Push the drum unit in until it stops.
k
Close the front cover of the machine.
When you replace the drum unit with a new one, you need to reset the drum counter by completing the
following steps:
a Press + or - to choose Machine Info.. Press OK.
b Press + or - to choose Reset Parts Life. Press OK.
c
Press + to choose Drum Unit. Press OK.
d Press + to reset the drum unit counter.
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