Brother MFC-P2000 - B/W Laser Printer Service Manual page 89

I-19 Downward fogging of solid black
<Printing>
Possible cause Step
Drum unit
High-voltage
power supply
PCB
I-20 Horizontal lines
<Printing>
Possible cause Step
SR electrode
SR connection
failure
Feed roller
Check
1 Is the problem solved after
replacing the drum unit?
2 Is the problem solved after
replacing the high-voltage
power supply PCB?
Check
1 Are the SR electrodes
between the printer body and
the drum unit dirty?
2 Are the SR electrodes
between the printer body and
the drum unit connected
correctly?
3 Are the feed roller shaft and
the ground contact
connected correctly?
Result
Yes
Yes
Result
Yes
No
No
IV-20
Remedy
Replace the drum unit.
Replace the high-voltage
power supply PCB.
Remedy
Clean both electrodes.
Check the SR
connection.
Check the connection
between the shaft and
the ground contact.
GND
contacts
(Fig.4-5,
4-7)