Brother HL-2290 Service Manual page 90

 All black
<User Check>
Step
Dirt on the electrodes of the
1 drum unit and those of the
machine
2 Laser unit flat cable failure
Dirt on the electrodes of the
high-voltage power supply
3
PCB and those of the
machine
High-voltage power supply
4
PCB failure
5 Laser unit failure
6 Main PCB failure
 Dirt on back side of paper
Step
1 Dirt in the paper feed system
2 Dirt on the fuser unit
High-voltage power supply
3
PCB failure
• Clean the corona wire of the drum unit.
• Replace the drum unit with a new one.
Cause
<User Check>
• This problem may disappear after printing multiple
sheets of paper.
• Replace the drum unit with a new one.
Cause
2-68
Remedy
Clean the electrodes of the drum unit and
those of the machine. (Refer to
42) and Fig. 2-9 (P2-42).)
Replace the laser unit flat cable.
Clean the electrodes of the high-voltage
power supply PCB and those of the machine.
Replace the high-voltage power supply PCB
ASSY.
Replace the laser unit.
Replace the main PCB ASSY.
Remedy
Wipe dirt off.
Replace the fuser unit.
Replace the high-voltage power supply PCB
ASSY.
Fig. 2-8 (P2-
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