Brother HL-L9300CDW Service Manual page 128

■
One color band
<User Check>
- Clean the corona wire of all four colors on the drum unit.
- Return the cleaning tab of the corona wire to the
- This symptom might stop occurring after making several prints.
- Refer to the User's guide and remove the dirt on the exposure drum using a cotton swab.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
Step
1 Installation failure of each FG
wire and/or FG plate
(Grounding is not performed
correctly.)
2 Dirt on the exposure drum
3 Laser unit failure
■
Downward fogging of solid color
<User Check>
Step
1 High-voltage power supply
PCB failure
2 Main PCB failure
■
Horizontal lines
Step
1 Dirt on charged electrode
2 Dirt on the exposure drum
3 Scratch and dirt on fuser unit
4 High-voltage power supply
PCB failure
Cause
- Replace the toner cartridge with a new one.
Cause
<User Check>
- This symptom might stop occurring after making
several prints.
- Refer to the User's guide and remove the dirt on the
exposure drum using a cotton swab.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
Cause
2-108
position.
Remedy
Retighten the screws of each FG wire and/or
FG plate. Repair the bend of the tray ground
spring of the paper tray.
(Refer to Fig. 2-11 (P2-102).)
Perform drum cleaning.
(Refer to "2.1 Drum Cleaning" in Chapter
Replace the laser unit.
Remedy
Replace the high-voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
Remedy
Clean the electrodes of the drum unit and
main body.
(Refer to Fig. 2-6 (P2-57),
Perform drum cleaning.
(Refer to "2.1 Drum Cleaning" in Chapter
Replace the fuser unit.
Replace the high-voltage power supply PCB
ASSY.
5.)
Fig. 2-5 (P2-57).)
5.)
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