Brother DCP-L8400CDN, Service Manual

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2-106
Confidential
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Light vertical steaks and bands on one color image
< User Check >
- Clean the corona wire of all four colors on the drum unit.
- Check if dust adheres to the area of the toner cartridge corresponding to the location where
the white vertical streak appears.
- Refer to the User’s guide and remove the dirt on the exposure drum using a cotton swab.
- Wipe the scanner windows of the laser unit with a soft, lint-free cloth.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
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White horizontal stripes on one color image
< User Check >
- This symptom might stop occurring after making several prints.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
Step Cause Remedy
1 Dirt on charged electrode Clean the electrodes of the drum unit and the
main body.
(Refer to
Fig. 2-8 (P2-55) , Fig. 2-7 (P2-55) .)
2 Dirt on the exposure drum Perform drum cleaning.
(Refer to
“2.2 Drum Cleaning” in Chapter 5 .)
3 Laser unit failure Replace the laser unit.
Step Cause Remedy
1 Dirt on charged electrode Clean the electrodes of the drum unit and the
main body.
(Refer to
Fig. 2-8 (P2-55) , Fig. 2-7 (P2-55) .)
2 Dirt on the exposure drum Perform drum cleaning.
(Refer to
“2.2 Drum Cleaning” in Chapter 5 .)
3 Scratch and dirt on fuser unit Replace the fuser unit.
4 High-voltage power supply
PCB failure Replace the high-voltage power supply PCB
ASSY.