Brother HL-L8250CDN Service Manual page 115

■
Dark
<User Check>
Step
1 Dirt on the electrodes of the
main body and the drum unit
2 Dirt on the electrodes of the
main body and the toner
cartridge
3 Dirt on the electrodes of the
main body and the belt unit
4 Dirt on the electrodes of the
high-voltage power supply
PCB
5 Density sensor failure
6 Fuser unit failure
7 High-voltage power supply
PCB failure
8 Main PCB failure
9 Laser unit failure
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Poor fixing
<User Check>
Step
1 Dirt on the electrodes of the
main body and the belt unit
2 Fuser unit failure
3 High-voltage power supply
PCB failure
4 Low-voltage power supply
PCB failure
5 Laser unit failure
6 Main PCB failure
- Check the machine's environment. High temperature and high humidity
or low temperature and low humidity conditions can cause this problem.
- After a new toner cartridge is detected, check if other toner cartridge is
not inserted.
- Execute density adjustment from the control panel.
- Clean the corona wire of all four colors on the drum unit.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
- Replace the belt unit with a new one.
Cause
- Check the machine's environment. High temperature and high humidity
or low temperature and low humidity conditions can cause this problem.
- Clean the corona wire of all four colors on the drum unit.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
- Replace the belt unit with a new one.
- Wipe the scanner windows of the laser unit with a soft, lint-free cloth.
Cause
2-92
Remedy
Clean the electrodes of the main body and
the drum unit.
(Refer to Fig. 2-5 (P2-55),
Clean the electrodes of the main body and
the toner cartridge.
(Refer to Fig. 2-5 (P2-55),
Clean the electrodes of the main body and
the belt unit.
(Refer to Fig. 2-5 (P2-55),
Clean the electrodes of the high-voltage
power supply PCB.
Replace the registration mark sensor unit.
Replace the fuser unit.
Replace the high-voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
Replace the laser unit.
Remedy
Clean the electrodes of the main body and
the belt unit.
(Refer to Fig. 2-5 (P2-55),
Replace the fuser unit.
Replace the high-voltage power supply PCB
ASSY.
Replace the low-voltage power supply PCB
unit.
Replace the laser unit.
Replace the main PCB ASSY.
Fig. 2-6 (P2-55).)
Fig. 2-8 (P2-90).)
Fig. 2-9 (P2-91).)
Fig. 2-9 (P2-91).)
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