Brother FAX-2840 Service Manual page 104

Faulty registration
Step
Adjusted value of the laser unit is
1 incorrect.
Registration rear actuator catching on
2
some position
Dark
<User Check>
- Check the machine's environment. High temperature and high
- Adjust the density by the Density Adjustment.
- Clean the corona wire of the drum unit.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one. Replacing the relatively
- If this problem occurs immediately after deep sleep mode is
Step
Dirt on electrodes of the drum unit
1 and those of the machine
High voltage power supply PCB
2
failure
3 Laser unit failure
4 Main PCB failure
<User Check>
- Check that the appropriate media type is selected in the
driver.
Cause
humidity or low temperature and low humidity conditions can cause
this problem.
new toner cartridge with a used toner cartridge can cause this
problem.
released, install the latest firmware. If installing the firmware is not
possible, open and close the front cover, and then retry printing after
the main motor has stopped.
Cause
2-67
Remedy
Refer to "2.1 Entering the Adjusted Value of
the Laser Unit" in Chapter
adjusted value of the laser unit again.
Correct the position of the registration rear
actuator.
Remedy
Clean the electrodes of the drum unit and
those of the machine. (Refer to
and Fig. 2-11.)
Replace the high voltage power supply PCB
ASSY.
Replace the laser unit.
Replace the main PCB ASSY.
4, and enter the
Fig. 2-10
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