Brother DCP-L8400CDN Service Manual page 131

■
Completely blank
< User Check >
- 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.
- Install the latest firmware.
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 Connection failure of the laser
unit flat cable
5 Laser unit flat cable failure
6 Dirt on the electrodes of the
high-voltage power supply
PCB
7 Laser unit failure
8 Main PCB failure
■
Image distortion
< User Check >
- Replace the belt unit with a new one.
Step
1 Laser unit installation failure
2 Laser unit failure
3 Main PCB failure
Cause
Clean the electrodes of the main body and
the drum unit.
(Refer to
Clean the electrodes of the main body and
the toner cartridge.
(Refer to
Clean the electrodes of the main body and
the belt unit.
(Refer to
Reconnect the laser unit flat cable.
Replace the laser unit flat cable.
Clean the electrodes of the high-voltage
power supply PCB.
Replace the laser unit.
Replace the main PCB ASSY.
Cause
Re-assemble the laser unit.
Replace the laser unit.
Replace the main PCB ASSY.
2-101
Remedy
Fig. 2-7 (P2-55), Fig. 2-8
Fig. 2-7 (P2-55), Fig. 2-10
Fig. 2-7 (P2-55), Fig. 2-11
Remedy
(P2-55).)
(P2-98).)
(P2-99).)
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