Brother HL-5440D Service Manual page 102

Black vertical streaks in a light background
<User Check>
- Clean inside the machine and the corona wire of the drum unit.
- Refer to the User's Guide to remove the dirt from the exposure drum
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
Step
1 Dirt on paper feed system
2 Scratches or dirt on the heat unit
3 Foreign object in the laser unit
Black band
<User Check>
- Clean inside the machine and the corona wire of the drum unit.
- Return the corona wire cleaning tab to the [
- The paper tray earth spring on the machine side may be dirty.
- Replace the toner cartridge with a new one.
- Replace the drum unit with a new one.
Step
1 Tray earth spring is bent.
Vertical streaks
<User Check>
- Check that there is no dust in the clearance between the toner
- Replace the toner cartridge with a new one.
- Check the usage environment of the machine. Using the machine in
- Check that the paper is not damp.
- Turn ON the power switch, and leave the machine for a while.
- Replace the drum unit with a new one.
Step
1 Laser unit failure
using a cotton applicator.
Cause
Clean it with a dry cloth.
Cause
cartridge and the drum frame.
high temperature and humidity or low temperature and humidity
conditions can cause this problem.
Cause
2-66
Remedy
Wipe off the dirt.
Replace the fuser unit.
Replace the laser unit.
] position.
Remedy
Replace the paper tray.
Remedy
Replace the laser unit.
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