Brother HL-1850 Service Manual page 237

I-22 Light rain
Possible cause Step
Drum unit failure 1
Drum 2
connection
failure
High-voltage 3
power supply
PCB failure
I-23 Ghost
User Check
(1) Check the paper used meets the recommended paper specifications. Damp
paper, thick media or rough surfaced paper can cause the problem.
(2) Check the printer's environment. High temperature and high humidity conditions
can cause the problem.
(3) Check that the appropriate media type is selected in the printer driver.
(4) Try installing a new drum unit.
Possible cause Step
Driver setting 1
Drum unit failure 2
High-voltage 3
power supply
PCB failure
Check
Is the problem solved after
replacing the drum unit?
Is the contact between the
drum unit and printer body
connected correctly?
Is the problem solved after
replacing the high-voltage
power supply PCB?
Check
Is thin paper such as 64g/m
used under the thick paper
mode?
Is the problem solved after
replacing the drum unit?
Is the problem solved after
replacing the high-voltage
power supply PCB?
6-53
Remedy
Result
Yes Replace the drum
unit.
No Clean contact
electrode both on the
drum unit and in the
printer body.
Yes Replace the high-
voltage power supply
PCB.
Result
2
Yes 1) Change the current mode to
the normal mode from the
driver setting.
2) Print 5 or 6 blank pages if
this problem occurs.
Yes Replace the drum unit.
Yes Replace the high-voltage power
supply PCB.
HL-1850/1870N SERVICE MANUAL
Ground
contact
(8)
Remedy