Service Manual
Troubleshooting
7-26
Samsung Electronics
Fault
Signs
Cause & Check
Solution
White Black spot
Recycled product
• Light or dark black
dots on the image
occur periodically.
• White spots occur
in the image
periodically.
• Poor appearance of
the toner cartridge.
• Dirty or rough
printouts.
• Bad background in
the image.
1. If light or dark black dots
occur at regular intervals this
is because the toner cartridge
rollers are contaminated with
foreign substance or paper
particles.
(1)38mm interval : Charge
roller
(2)95mm interval : OPC cycle
2. If white spots occur in a black
image at intervals of 95mm,
or black spots occur
elsewhere, the OPC drum is
damaged or foreign
substance is stuck to the
surface.
3. If a black and white or
graphic image is partially
broken at irregular intervals,
the transfer roller's life has
been expired or the transfer
voltage is abnormal.
1. Poor appearance of the toner
cartridge.
(a)Check for damage to label
and if different materials are
used.
(b)Check the appearance of
parts of the toner cartridge,
such as frame, hopper, screws
2. Unclean and rough printouts.
(a)Check that the terminals
(contact point) of the toner
cartridge and the set are clean.
(b)Check that the terminals
(contact point) of the toner
cartridge and the set are not
damaged.
1. For item 1 -
Run OPC Cleaning Mode Print
4-5 times repeatedly to remove
excess toner. Especially check
for foreign substances on the
OPC surface Clean with a clean
gauze moistened with IPA
Isopropyl Alcohol) take care not
to damage the OPC surface.
Never use other forms of alcohol.
2. For Item 2 -
If running OPC Cleaning Mode
Print 4-5 times does not resolve
the problem
: at intervals of 37.7mm - place
the toner cartridge.
: at intervals of 75.5mm – clean
OPC drum.
3. For item 3 - Change the transfer
roller because the life of the
transfer roller has expired.
(Check the transfer voltage and
readjust if necessary.)
1. For Item 1 the cartridge is judged
to be a recycled product -
(a) If there is any evidence of
disassembling the toner cartridge.
(b) If materials other than normal
parts of the toner cartridge are
added or substituted.
2. Clean all HV contacts. If the
problem persists replace the
cartridge.
Note If the cartridge is judged to be
recycled then these types of
problems can occur when the
toner cartridge is recycled over
2 times.
If ‘nearly empty’ cartridges are
collected for re-use this is
judged as recycling the toner
cartridge.
Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer
Summary of Contents for SCX-4520
Page 10: ...Service Manual Reference Information 2 4 Samsung Electronics 2 3 2 A4 2 Pattern ...
Page 11: ...Reference Information Samsung Electronics Service Manual 2 5 2 3 3 A4 IDC 5 Patten ...
Page 14: ...Service Manual Reference Information 2 8 Samsung Electronics MEMO ...
Page 24: ...Service Manual Specifications 3 10 Samsung Electronics MEMO ...
Page 27: ...Summary of Product Service Manual 4 3 Samsung Electronics 4 1 3 Control Panel SCX 4720F ...
Page 28: ...Service Manual Summary of Product 4 4 Samsung Electronics ...
Page 51: ...Summary of Product Service Manual 4 27 Samsung Electronics MEMO ...
Page 163: ...Service Manual Exploded View Parts List 8 28 Samsung Electronics MEMO ...