Troubleshooting procedures – Brother MFC 7550MC User Manual
Page 220
TROUBLESHOOTING PROCEDURES
16-15
MFC 4550/6550MC/7550MC
OP-US-5.0
Printouts
are
too
dark
or
light.
Question
Recommendation
Adjust
the
conditions
by
setting
the
Density
function,
or
turn
the
density
dial
counterclockwise
for
lighter
images
and
clockwise
for
darker
images.
It
has
been
factory
set
to
the
middle
position.
See
“The
is
too
Light
or
too
Dark”on
You
may
fix
this
by
wiping
the
scanner
windows
with
a
clean
soft
cloth.
(See
“Regular
Maintenance”
and
“Cleaning
the
Drum
Unit”
If
the
same
problem
occurs
and
the
display
shows
CHANGE
DRUM,
replace
the
drum
unit
with
a
new
one.
• Clean
the
machine
interior
and
the
primary
corona
wire
of
the
toner
cartridge.
See
“Regular
Maintenance”
and
“Cleaning
the
Drum
• Make
sure
that
the
tab
of
the
corona
wire
is
at
the
home
position.
If
the
same
problem
occurs
and
the
display
shows
CHANGE
DRUM,
after
cleaning,
replace
the
drum
unit
with
a
new
one.
Make
sure
that
you
use
paper
that
meets
the
specifications.
Rough
surface
or
thick
media
can
cause
the
problem.
If
you
still
have
the
same
problem
and
the
display
shows
CHANGE
DRUM,
replace
the
drum
unit
with
a
new
one.
Printed pages are
stained
with
toner
or
have
vertical
stripes.
Printed
pages
contain
white
stripes.
White Stripes or Faint
lmages
White Spots
NOTICE
Printed pages have
white
spots
in
black
text
and
graphics
area.
Dark Stripes or Toner
Stains
Print Quality Problems
You
will
clear
a
quality
problem
by
replacing
the
drum
unit
with
a
new
one
if
the
display
will
show
CHANGE
DRUM.
The
old
drum
unit
is
at
the
end
of
its
life.