White Vertical Streaks On One Color Image; White Horizontal Stripes On One Color Image - Brother HL-4140CN Service Manual

■ White vertical streaks on one color image

<User Check>
- Check if there is no dust in the gap between the toner cartridge and drum frame.
- Wipe the scanner windows of the laser unit with a soft, lint-free cloth.
(Refer to Fig. 2-12
- Refer to the User's guide and remove the dirt on the exposure drum using a cotton swab.
- Replace the toner cartridge with a new one.
- Check the printer's environment. High temperature and high humidity or low temperature
and low humidity conditions can cause this problem.
- Damp (wet) paper might be used. Try to change to freshly unpacked paper.
- Replace the drum unit with a new one.
Step
1 Condensation
2 Exposure drum dirty
3 Laser unit failure

■ White horizontal stripes on one color image

<User Check>
- The problem may disappear by itself. Try printing multiple pages to clear this problem
especially if the printer has not been used for a long time.
- Replace the toner cartridge with a new one.
- The drum unit may be damaged. Replace the drum unit with a new one.
Step
1 High-voltage power supply
PCB failure
2 Engine PCB failure
(P2-95))
Cause
Cause
2-103
Remedy
Try to print several pages or leave the printer
2 hours to allow it to reach room
temperature.
Refer to "2.8 Drum Cleaning" in Chapter 5
and perform drum cleaning.
Replace the laser unit.
Remedy
Replace the high-voltage power supply PCB
ASSY.
Replace the engine PCB ASSY.
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