Pitch Indicated In Roller Image; Troubleshooting Image Defect - Brother MFC-9320CW Service Manual

4.2

Pitch Indicated in Roller Image

Image defects which occur periodically may be caused by a failure of the roller. By referring to
the table below, specify the cause based on the pitch indicated in the image of each roller.
No.
1 Develop roller
2 Exposure drum
3 Heat roller in the fuser unit
4 Pressure roller in the fuser unit
4.3

Troubleshooting Image Defect

Image defect related problems are user recoverable if following the User Check items. If the
same problem occurs, follow each procedure in the order of the number described in the Step
column in the tables below.
■ Light on the whole page
Step
1 HVPS control PCB
failure
2 High-voltage power
supply PCB failure
3 Engine PCB failure
4 Main PCB failure
5 LED head control
PCB failure
6 LED ASSY failure
7 Registration mark L
PCB failure
Parts name
<User Check>
- Check the machine's environment. High temperature and high humidity
or low temperature and low humidity conditions can cause this problem.
- If the whole page is light, toner save mode may be on. Turn off the toner
save mode.
- Replace the toner cartridge or drum unit with a new one.
- Adjust the color density from the control panel cover ASSY.
- Leave the machine for a while as the power remains ON.
Cause
Is the problem solved
after replacing the HVPS
control PCB ASSY?
Is the problem solved
after replacing the
high-voltage power
supply PCB ASSY?
Is the problem solved
after replacing the
engine PCB ASSY?
Is the problem solved
after replacing the main
PCB ASSY?
Is the problem solved
after replacing the LED
head control PCB ASSY?
Is the problem solved after
replacing the LED ASSY?
Is the problem solved
after replacing the
registration sensor
holder ASSY?
The pitch which appears in the image
Check
Result
Yes
Yes
Yes
Yes
Yes
Yes
Yes
3-61
31 mm
94 mm
78 mm
78 mm
Remedy
Replace the HVPS
control PCB ASSY.
Replace the
high-voltage power
supply PCB ASSY.
Replace the engine
PCB ASSY.
Replace the main PCB
ASSY.
Replace the LED head
control PCB ASSY.
Replace the LED ASSY.
Replace the
registration sensor
holder ASSY.
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