Brother DCP7010 Service Manual page 229

I-16 Black spots
(1) If the problem is not solved after printing a few pages, the drum unit may
(2) The drum unit may be damaged. Install a new drum unit.
Possible cause
Step
Drum unit 1
Drum 2
connection
failure
Fixing unit 3
High-voltage 4
power supply
PCB failure
User Check
have glue from label stock on the exposure drum surface. Refer to Step 1
in the table below and
Check
Are the spots at 74mm
intervals?
(The problem is not solved
after printing a few pages.)
Is the contact between the
drum unit and printer body
connected correctly?
Are the spots at 79mm
intervals?
(The problem is not solved
after printing a few pages.)
Is the problem solved after
replacing the high-voltage
power supply PCB?
9 -4 1
NOTE in the next page.
Result
Yes 1) If toner or glue
remains stuck, wipe it
off gently with a
cotton swab. (Refer
to
previous page.)
2) If the exposure drum
is scratched or
deteriorated
(exposed), replace the
drum unit.
No Clean contact electrode
both on the drum unit
and in the printer body.
Yes 1) Check and clean the
heat roller with a
cloth dampened with
alcohol.
2) Replace the fixing
unit.
Yes Replace the high-
voltage power supply
PCB.
Remedy
NOTE in the
Confidential
Ground
contacts
(7)