Brother HL-L9200CDWT - Manual (Page 170)

Routine Maintenance
163
5
Cleaning the drum unit
5
If your printout has colored, white, or black dots at 3.7 in. (94 mm) intervals, the drum may have foreign
material, such as glue from a label stuck on the drum surface. Follow the steps below to solve the problem:
a
Make sure the machine is in Ready mode.
b
Press .
c
Press Machine Information > Drum Dot Print.
d
Press OK to print the drum dot check sheet.
e
Press and hold down to turn the machine off.
f Press the front cover release button and pull open the front cover.
g Hold the blue handle of the drum unit. Pull the drum unit out until it stops.