Brother DCP7010 Service Manual page 219

I-4 All black
(1) Clean the corona wire of the drum unit.
(2) The drum unit may be damaged. Install a new drum unit.
Possible cause
Step
Corona failure 1
2
3
Harness 4
connection
High-voltage 5
power supply
PCB failure
Main PCB 6
failure
Laser unit 7
failure
User Check
Check
Is the corona wire dirty?
Is the corona wire broken?
Are the charge electrodes
between the printer body
and the drum unit dirty?
Is the laser unit connected
to the main PCB correctly?
Is the problem solved after
replacing the high-voltage
power supply PCB?
Is the problem solved after
replacing the main PCB?
Is the problem solved after
replacing the laser unit?
9 -3 1
Remedy
Result
Yes Clean the corona wire
with the wire cleaner.
Yes Replace the drum unit.
Yes Clean both electrodes.
No Connect the harness
between the laser unit
and the main PCB
correctly.
Yes Replace the high-
voltage power supply
PCB.
Yes Replace the main PCB.
Yes Replace the laser unit.
Ground
contacts
(2)
(3)
Confidential