Samsung SCX 4520, SCX-4521F, SCX4720F Troubleshootin

Troubleshooting

Service Manual

7-1

Samsung Electronics

7

7

7. Troubleshooting

7.1 Paper Feed problems – Causes and Solutions

7.1.1 Wrong Print Position

• Description Printing begins when the paper is in the wrong position.

Check and Cause Solution

A defective feed sensor actuator can cause incorrect
timing.

Replace the defective actuator

7.1.2 JAM 0

• Description

1. Paper does not exit from the cassette.

2. Jam-0 occurs when the paper feeds into the printer.

PTL

P

I

C

K

/

R

PR

CR

DR

SR

TR FR

Empty Sensor

OPC

L S U

Fuser

Toner Cartridge

EXIT
Sensor

Feed

Sensor

MP Sensor

Check and Cause Solution

1. Check the Solenoid by using Tech
Mode.

2. Check cassette/MP knock-up plate
and springs.

3. Check paper separator pad

4. Check the pick up roller for
contamination and correct assembly.

5. If continuous clusters occur, check all
rollers between pickup and registration
sensor.

6 If the paper feeds into the printer and

Jam 0 occurs, perform Tech Mode to
check feed sensor.

1. Replace the solenoid.

2. Repair / replace as required

3 Clean with soft cloth dampened with

IPA (Isopropyl Alcohol) or water.
Replace if required.

4. Clean with soft cloth dampened with
IPA (Isopropyl Alcohol) or water.
Replace if required

5. Ensure all rollers are clean and free to
operate correctly.

6. Check the SMPS PBA, Main PBA and
all connections. Replace any faulty
parts or the

Service Manual

Troubleshooting

7-2

Samsung Electronics

7.1.4 JAM 2

• Description

1. Recording paper is jammed in front of or inside the fuser.

2. Recording paper is stuck in the discharge roller and in the fuser just after passing through the
Actuator-Feed.

Check and Cause Solution

1. If the paper is completely fed out of
the printer, but Jam 2 occurs: The
Exit sensor may be defective.

• After the paper is completely

discharged the Exit sensor actuator
should return to its original position
to shut the photo-sensor. It may
stick open or return only slowly due
to contamination be paper debris or
foreign objects.

2. If the paper is rolled in the Fuser
Roller:

• This occurs when a Guide claw is

broken away, damaged or
deformed.

• It occurs when the Spring of a
Guide claw is broken or damaged.

• It occurs when the Heat-Roller or
Pressure-Roller is seriously
contaminated with toner.

1. Check if the exit sensor actuator is
defective.

• Check if the actuator exit is deformed
(Check if the lever part is deformed).

• Check whether burrs occur in the
assembly part of the exit actuator
and if the actuator operates smoothly.

• Check if foreign objects or paper
debris are preventing the correct
operation of the actuator.

2. If the paper is stuck in the fuser :
disassemble the fuser and remove the
jammed paper, and clean the surface
of the pressure roller with dry gauze.
Check all ribs, claws and springs.

7.1.3 JAM 1

• Description

1. Recording paper is jammed in front of or inside the fuser.

2. Recording paper is stuck in the discharge roller and in the fuser just after passing through the
Actuator-Feed.

Check and Cause Solution

1. If the recording paper is jammed in
front of or inside the fuser.

2. If the recording paper is stuck in the
discharge roller and the fuser just
after passing through the Actuator­Feed, Feed Actuator may be defec
tive.

1. Replace the SMPS.

2. Reassemble the Actuator-Feed and
Spring-Actuator if the return is bad.

Fuser

EXIT

PR

Sensor

Fuser

EXIT

PR

Sensor

Empty Sensor

L S U

CR

OPC

Toner Cartridge

DR

SR

PTL

Feed

Sensor

TR FR

MP Sensor

R

/

K

C

I

P

L S U

Empty Sensor

CR

DR

OPC

PTL

TR FR

Toner Cartridge

SR

Feed

Sensor

R

/

K

C

I

P

MP Sensor

Troubleshooting

Service Manual

7-3

Samsung Electronics

7.1.5 Multi-Feeding

• Description Multiple sheets of paper are fed at once.

Check and Cause Solution

1. Check that the paper size guides are set correctly
(cassette and MPF tray).

2. Solenoid malfunction (the solenoid does not work
properly).

3. Friction Pad is contaminated.

4. Paper has a rough surface texture.

1. Adjust paper guides.

2. Replace the solenoids or PBA as appropriate.

3. Clean the friction pad rubber with a soft cloth
dampened with IPA (Isopropyl Alcohol) or water.

4. Use paper with a smother surface finish.

7.1.6 Paper rolled in the fuser

• Description Paper rolled around fuser rollers or ‘Concertina’ jam

Check and Cause Solution

1. Contamination of the pressure roller or heat roller.

2. Damaged or deformed ribs, claws or springs.

1. After disassembling the fuser, clean contamination
from between the heat roller and the thermistor and
also clean contamination from the pressure roller.
Clean the surface of the rollers with IPA or water

2. Check for damage or deformation of the print claws
and the holder plate claws, and repair or replace as
appropriate.

Service Manual

Troubleshooting

7-4

Samsung Electronics

7.1.7 Paper rolled on the OPC Drum

• Description Paper is rolled up in the OPC.

Check and Cause Solution

1. Paper is too thin.

2. The face of paper is curled.

1. Use paper that conforms to the printer specification.

2. Ensure paper is stored properly to prevent curl.
Note. To remove paper rolled in the OPC.

• Remove the toner cartridge from the set, taking

care not to touch the green surface. Use the
gearwheel at the side to rotate the OPC drum and
pull the paper from the cassette.

• Clean fingerprints on the OPC gently with soft

tissue, taking care not to scratch the surface.

7.1.8 Defective ADF

• Description ADF (Automatic document Feeder) does not operate correctly.

Check and Cause Solution

1. Check if the ADF rubber or HOLDER rubber are
damaged or contaminated.

2. Check if the ADF Ass'y document sensors (3 paper
sensors) are working correctly.

1. Replace the contaminated or damaged part.

2. If you cannot confirm the damaged part with the

Troubleshooting

Service Manual

7-5

Samsung Electronics

7.2 Set Malfunction – Causes and Solutions

7.2.1 LCD Display Defect ( in LCD Display)

• Description

Strange characters are displayed in the LCD Window and OPE Panel buttons do not work.

Check and Cause Solution

1. Clear the memory. (see page 6-18)

2. Check that the OPE HARNESS is connected to
the Connection Board correctly.

1. Try again after clearing the memory.

2. If re-connecting the harness does not correct
the fault replace the OPE Ass’y and the main
Board in sequence.

7.2.2 Defective OPE Keypad

• Description

Pressing keys does not cause the set to respond correctly

Check and Cause Solution

1. Clear the memory. (See page 6-18).

2. Check that there is an audible key click when a key is
pressed.

1. Check that the keypad is assembled correctly and
the membrane is not damaged, replace the
membrane or whole keypad assembly if necessary.

2. If the fault remains replace the OPE Ass’y and the
Main board in sequence.

Service Manual

Troubleshooting

7-6

Samsung Electronics

7.2.3 Fuser gear melts due to overheating causing Paper Jam.

• Description

Constant Jam where paper is entering Fuser unit.
Fuser rollers do not turn

Check and Cause Solution

1. Check the Heat Lamp, thermostat and thermistor 1. Use EDC Mode to test the fuser.
Replace Fuser unit

Replace SMPS or Main PBA as appropriate.

7.2.4 Paper Empty

• Description

Paper Empty is displayed in the LCD panel even when paper is loaded in the cassette.

Check and Cause Solution

1. Deformed paper sensor actuator or faulty sensor.

2. SMPS PBA or Main PBA is defective

3. Faulty cables or connectors.

1. Replace the defective actuator or sensor.

2. Replace the SMPS PBA or MAIN PBAas
appropriate.

7.2.5 Paper Empty without indication

• Description

The paper empty message does not appear in the LCD when the paper cassette is empty.

Check and Cause Solution

1. Deformed paper sensor actuator or faulty sensor.

2. SMPS PBA or Main PBA is defective
.

1. Replace the defective actuator.

2. Replace the SMPS PBA or MAIN PBAas
appropriate

Troubleshooting

Service Manual

7-7

Samsung Electronics

7.2.7 No error message when the cover is open

• Description

The Cover Open message does not appears on the LCD even when the print cover is open.

Check and Cause Solution

1. The ‘Open Cover’ microswitch may be stuck or faulty

2. Check the connector and cables between Switch and
main PBA.

1. Use

TECH

mode(“cover sensor test”) to check
cover switch operation. Check and replace switch if
necessary .

2. Replace the Main Control board or Cover Open
S/W as necessary.

7.2.6 Cover Open

• Description

The Cover Open message appears on the LCD even when the print cover is closed.

Check and Cause Solution

1. The ‘Open Cover’ microswitch may be stuck or faulty

2. The tab on the front cover may be damaged or broken

3. Check the connector and cables between Switch and
main PBA.

1. Use

TECH

mode(“cover sensor test”) to check
cover switch operation. Check and replace switch if
necessary .

2. Replace the front cover.

3. Replace the Main Control board or Cover Open
S/W as necessary.

Service Manual

Troubleshooting

7-8

Samsung Electronics

7.2.10 Printed Vertical Lines become curved

• Description

When printing, vertical lines are not straight.

Check and Cause Solution

1. Check stability of 24V supply to LSU. 1. 24V stable - Replace LSU.
24V unstable replace SMPS, if the problem persists
replace the main PBA.

7.2.8 Defective motor operation

• Description

Main motor is faulty and paper does not feed into the printer, resulting in Jam 0'

Check and Cause Solution

1. The main motor harness or Motor PCB may be faulty. 1. Check the motor harnesses and connectors, replace
if defective.. If the problem persists replace the main
PBA.

Note Check motor operation using EDC Mode.

7.2.9 No Power

• Description

When system power is turned on the LCD panel does not come on.

Check and Cause Solution

1. Check if the power input and SMPS output are normal.

2. LCD panel does not come on but normal start up

sounds are heard.

3. After replacing SMPS display does not come on and no

start up sounds are heard.

1. Replace the power supply cord or SMPS. Check
power fuse and SMPS fuses replace if necessary.

2. Replace the OP panel.

3. Replace the main PBA panel.

Troubleshooting

Service Manual

7-9

Samsung Electronics

7.3 Paper Feed Problems – Causes and Solutions

7.3.1 Wrong Print Position

• Description Printing begins when the paper is in the wrong position.

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

A defective feed sensor actuator can cause
incorrect timing.

Replace the defective actuator

7.3.2 Vertical White Line

• Description White vertical voids in the image.

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. 1. Contamination of the window or
internal lenses of LSU mirror.

2. Foreign object inside the toner cartridge
or low toner.

3. Foreign object, contamination or burr on
the edge of the toner cartridge window.

4. If the fuser is defective, voids occur
periodically at the top of a black image.

5. Contamination of the OPC drum.

6. Depression or deformation of the surface
of the transfer roller

1. Clean the LSU window with recommended
cleaner (IPA) Clean the window with a
clean cotton swab. If dirt is inside the LSU
– replace LSU.

2. Replace the toner cartridge.

3. Clean the exposure window.

4. Open the front cover and check the ribs
that correspond to the position of the
voids. Remove if found.

5. If the problems are not solved, replace
the toner cartridge.

6. Replace the transfer roller.

Service Manual

Troubleshooting

7-10

Samsung Electronics

7.3.3 Horizontal Black Bands

• Description

1. Dark or blurry horizontal stripes occur in the printing periodically.
(These may occur at regular intervals down the page.)

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. Bad contacts on the toner cartridge high
voltage terminals.

2. The rollers in the toner cartridge may be
contaminated.
Charge roller = 37.7 mm
Supply roller = 44.9 mm
Develop roller = 35.2 mm
Transfer roller = 47.1 mm

1. Clean all HV terminals on the cartridge and
on the set frame. Ensure all toner or paper
dust particles are removed.

2. Clean the right Gear that has relatively
small tooth gap on the OPC.

3. If the problem persists replace the toner
cartridge.

7.3.4 Black/White Spot

• Description

1. Dark or blurry black spots occur periodically in the printing.

2. White spots occur periodically in the printing.

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. If dark or blurry black spots occur periodi­cally, the rollers in the Developer may be
contaminated with foreign matte or paper
particles.
( Charge roller : 37.7 mm interval

OPC drum : 75.5 mm interval)

2. If faded areas or voids occur in a black
image at intervals of 75.5 mm, or black
spots occur elsewhere, the OPC drum
surface is damaged.

3. If a black image is partially broken, the
transfer voltage is abnormal or the
transfer roller's life has expired.

1. Print several OPC cleaning Mode Prints
and then run the Self-test 2 or 3 times.

2. 75.5 mm repetition: Examine the surface of
the OPC drum and carefully clean with a
soft, lint free cloth. If unsuccessful replace
the cartridge.

37.7mm repetition: Replace the toner car­tridge

3. The transfer roller guarantees 60,000
sheets printing. If the roller's life is expired,
replace it.

Note. Cleaning the inside of the set to

remove excess toner particles or paper
dust will reduce the occurrence of this
problem..

Troubleshooting

Service Manual

7-11

Samsung Electronics

7.3.5 Light Image

• Description The printed image is light, with no ghost.

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. Toner Save mode enabled

2. Develop roller is contaminated or the
toner cartridge is almost empty.

3. Ambient temperature is below than 10°C.

4. Bad contact caused by dirty terminals on
the toner cartridge or set.

5. Abnormal output from the HVPS.
(Run EDC mode – see sections 6.5.1
and 6.5.3)

1. Ensure the Toner Save mode is off. Check
set and driver settings.

2. Replace the toner cartridge and try to print
out again.

3. Wait 30 minutes after printer is powered on
before you start printing.

4. Clean the cartridge and set contacts.
Generally clean dirt from inside the set.

5. Replace the HVPS if the problems are not
solved by the above four instructions.

7.3.6 Dark Image or a Black

• Description The printed image is dark.

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. No charge voltage in the engine board.

2. Charge voltage fault due to bad contact
between toner cartridge and set contacts.

3. VD0 signal of the Main PBA is Low state.

1. Check the state of the connector which
connects the engine board and HVPS.

2. Clean the high voltage charge terminals.

Note if 1 and 2 do not resolve the problem

and the problem persists replace the
HVPS.

3. Replace the LSU Unit or Main PBA.

Service Manual

Troubleshooting

7-12

Samsung Electronics

7.3.7 Uneven Density

• Description Print density is uneven between left and right.

Check and Cause Solution

1. The pressure force on the left and right
springs of the transfer roller is not even,
the springs are damaged, the transfer
roller is improperly installed, or the trans­fer roller bushing or holders are damaged.

2. The life of the Toner cartridge has
expired.

3. The toner level is not even on the toner
cartridge roller due to the damaged blade
or low toner.

1. Replace both the left and right bush and
spring assemblies.

2. Replace the toner cartridge and try to print out

3. Gently shake the toner cartridge and try
printing again. If the problem persists
replace the toner cartridge.

7.3.8 Background

• Description Light dark background appears in whole area of the printing.

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. Printing large quantities of low coverage
(2%) pages or the printer has not been
used for a long time.

2.

Is a recycled toner cartridge be
used?

3.

Has the life span of the toner
cartridge ended?

4.

Is the movement(Up and Down) of
the transfer roller smooth?

5. Is the HVPS normal?

1. The toner cartridge is basically designed to
print 3,000 sheets with 5% image. If it
prints more than 3,600 sheets with 2%
coverage, a background can occur.

2. The A/S is not guaranteed if using a recy­cled toner cartridge.

Note try shaking the toner cartridge gently

from side to side. If the problem persists
replace the toner cartridge.

3. Replace the toner cartridge when its life is
expired.

4. Clean the transfer roller bushes.

5. Clean the high voltage charge terminals.
If this does not resolve the problem replace
the HVPS.

Troubleshooting

Service Manual

7-13

Samsung Electronics

7.3.9 Ghost (1)

• Description Ghost occurs at 75.5 mm intervals of the OPC drum in the whole printing.

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

75.5 mm

Check and Cause Solution

1. Bad contacts caused by contamination
from toner particles between high voltage
terminal in the main body and the elec­trode of the Toner cartridge.

2. Bad contacts caused by contamination
from toner particles between high voltage
terminal in the main body and the one in
the HVPS board.

3. The life of toner cartridge is expired.

4. Transfer roller life (60,000 sheets) has
expired.

5. Low ambient temperature (below 10°C).

6. Damaged cleaning blade in the toner
cartridge.

1 and 2. Clean all HV contacts, If problem
persists replace the HVPS.

If problem still persists replace the Main PBA

3. Replace the toner cartridge and try to print
out.

4. Check the transfer roller lifetime and
replace it.

5. Wait about 30 minutes after power on
before using printer.

6. Replace the toner cartridge and try to print
out again

7.3.10 Ghost (2)

• Description

Ghost occurs at 75 mm intervals of the OPC drum in the whole printing.
(When printing on card stock or transparencies using manual feeder)

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

75 mm

Check and Cause Solution

When printing on card stock, thicker than
normal paper or transparencies, such as
OHP, a higher transfer voltage is required.

Ensure that the correct paper type is selected
in the printer driver or application software.
Remember to set back to normal paper after
use.

Service Manual

Troubleshooting

7-14

Samsung Electronics

7.3.11 Ghost (3)

• Description Ghost occurs at 66.3 or 75.5 mm intervals.

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

32 mm

Check and Cause Solution

1. Disassemble the fuser and remove any
contamination on the rollers. Clean any
contamination from between the
Thermistor and the Heat roller. (Caution:
Take care not to deform the rollers.)

Fuser contamination.

7.3.13 Stains on the Face of the Page

• Description The background on the face of the printed page is stained.

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. Toner leakage due to improperly sealed
toner cartridge.

2. If the transfer roller is contaminated,
stains on the face of page will occur.

1. Replace the toner cartridge.

2. If the transfer roller is contaminated, run
PC Cleaning Mode Print 2 or 3 times and
then perform Self-Test 2 or 3 times to
remove contamination.

7.3.12 Ghost (4)

• Description A White ghost occurs in a black image printing at 32 mm intervals.

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

32 mm

Check and Cause Solution

1. Problem in the toner cartridge, replace the
toner cartridge and try to print out again.

2. Check the HVPS supply voltage. Clean all
HV terminals on the cartridge and on the
set. Replace the HVPS if the problem
persists.

1. The life of the developer may be expired.

2. Abnormal output from the HVPS.
(Run EDC mode – see sections

6.5.1

and 6.5.3

)

Troubleshooting

Service Manual

7-15

Samsung Electronics

7.3.14 Stains on Back of Page

• Description The back of the page is stained at 47.1 or 75.4 mm intervals.

Digital
Digital Pri
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. 47.1mm : Transfer roller is contaminated.

2. 75.4mm : Pressure roller is contaminated.

1. Perform the OPC Cleaning Mode Print 2 or
3 times. Run Self-Test to remove the
contamination from the transfer roller.

Note. Replace the transfer roller if

contaminated severely.

2. Disassemble the fuser and clean the
H/R(Heat Roller) and P/R(Pressure roller).
Check and clean the area between the
H/R and the Thermistor. (Caution: Take
care not to deform the rollers.)

7.3.15 Blank Page Print out (1)

• Description Blank page is printed.

Check and Cause Solution

Bad ground contacts in OPC and/or toner
cartridge.

1. Check if the Ground-OPC or the OPC
Ground Zener diode are defective or open
circuit. (set inside left side).

2. Remove contamination of the terminals on
the toner cartridge and the unit.

7.3.16 Blank Page Print out (2)

• Description

1. Blank page is printed.

2. One or several blank pages are printed.

3. When the printer turns on, several blank pages print.

Check and Cause Solution

1. Abnormal solenoid.

1. Perform the engine self test using TECH
Mode to check if the Solenoid is normal.
If the problem persists replace the main
PBA

Service Manual

Troubleshooting

7-16

Samsung Electronics

7.4.1 No Dial Tone

• Description

There is no dial tone when the On-Hook dial button is pressed.

7.4 Fax & Phone Problems

Check and Cause Solution

1. Check that the telephone line cord supplied with
the set is connected to TEL LINE correctly.

2. Listen for a CLICK sound when the OHD key is
pressed.

3. Check the connection of the HARNESS between
the LIU and the Main B'd.

4. Check that the SPEAKER is connected correctly.

1. If the telephone cord is OK but there is no dial tone, try
plugging a normal telephone into the wall socket. I this
is OK then replace the LIU B'd.

2. If you cannot hear the OHD CLICK sound, the OPE
Ass'y may be defective. Replace the OPE Ass'y.

3. Check the Speaker connection and the harness
between the LIU and the Main PBA, replace as
necessary .

4. Use Tech mode / Modem Test to check that the
speaker and amplifier are working. Replace the Main B'd.

7.4.2 Defective MF DIAL

• Description

The MF DIAL is not functioning.

Check and Cause Solution

1. Check that the telephone line cord supplied with
the set is connected to TEL LINE correctly.

2. Listen for a CLICK sound when the keKEY is
pressed.

3. Check the connection of the HARNESS between
the LIU and the Main B'd.

4. Check that the SPEAKER is connected correctly.

1. If the telephone cord is OK but there is no dial tone, try
plugging a normal telephone into the wall socket. I this
is OK then replace the LIU B'd.

2. If you cannot hear the OHD CLICK sound, the OPE
Ass'y may be defective. Replace the OPE Ass'y.

3. Check the Speaker connection and the harness
between the LIU and the Main PBA, replace as
necessary .

4. Use Tech mode / Modem Test to check that the
speaker and amplifier are working. Replace the LIU
and Main B'd in sequence

Notes: Product supports MF DIAL type only.

Troubleshooting

Service Manual

7-17

Samsung Electronics

7.4.3 Defective FAX FORWARD/RECEIVE

• Description

FAX FORWARD/RECEIVE is not functioning.

Check and Cause Solution

1. Check that you can hear a dial tone by pressing
OHD.

2. Check that you can hear a RECEIVE tone when
MODEM testing in TECH Mode.

1. If MODEM testing is normal and there is no dial tone,
then try replacing the LIU B'd.

2. If testing the MODEM shows a fault replace the
Main B'd.

7.4.4 Defective FAX FORWARD

• Description

RECEIVE is functioning, but FORWARD is not functioning or received data is corrupt.

Check and Cause Solution

1. Check if there is a NOISE line by pressing on-hook
dial and listening.

2. Check that the destination fax machine can receive
forwarded faxes by using a different sending fax
machine (preferably from the same wall socket).

3. Check the cable between the set and the wall
socket for damage.

1. If you can hear a noisy line when using on-hook dial,
replace or repair the telephone line

2. Replace LIU.

3. Replace the line cord.

Service Manual

Troubleshooting

7-18

Samsung Electronics

7.4.5 Defective FAX RECEIVE (1)

• Description

FORWARD is functioning, but RECEIVE is not functioning or the received data is corrupt.

Check and Cause Solution

1. Check if there is a NOISE line by pressing on-hook
dial and listening

2. Use a different fax machine to receive from the
same sender (if possible on the same wall socket).

1. If you can hear a noisy line when using on-hook dial,
replace or repair the telephone line.

2. Replace the LIU.

Check and Cause Solution

1. Check if there is a NOISE line by pressing on-hook
dial and listening

2. Ask sender to send to another fax machine
(if possible connected to the same wall socket)

1. If you can hear a noisy line when using on-hook dial,
replace or repair the telephone line

2. Replace LIU or main PBA in sequence.

Check and Cause Solution

Check that the RECEIVE Mode is set to FAX MODE. If the fault persists even when the RECEIVE Mode is

changed to FAX MODE then replace the LIU and the
Main B'd in sequence.

7.4.6 Defective FAX RECEIVE (2)

• Description

Received data are lengthened or cut in the printing.

7.4.7 Defective FAX RECEIVE (3)

• Description

The phone is ringing continuously, but it set does not answer the call.

Troubleshooting

Service Manual

7-19

Samsung Electronics

7.4.8 Defective FAX RECEIVE (4)

• Description

Received data is reduced by more than 50% in the printing.

7.4.9 Defective Automatic Receiving

• Description

The automatic receiving function is not working.

Check and Cause Solution

Check the FAX status of the forwarding side. This is a problem with the sending fax machine.

Correct the setting on the remote machine..

Check and Cause Solution

1. Check that the RECEIVE Mode is set to FAX
MODE.

1. If the RECEIVE Mode is set to the TEL MODE, reset it
to the FAX MODE.

2. Even after the RECEIVE Mode is changed to the FAX
Mode, the problem persists then try to replace the LIU
and the Main B'd in sequence.

Service Manual

Troubleshooting

7-20

Samsung Electronics

7.5.1 White Copy

• Description

Blank page is printed out when copying.

7.5 Copy Problems

7.5.2 Black Copy

• Description

Black page is printed out when Copying.

Check and Cause Solution

1. Check for CCD problem on the Main PBA.

2. Check shading profile.

1. Check the CCD harness is properly connected.

2. Redo shading profile in the tech mode.

Check and Cause Solution

1. Check the Scanner Cover is properly closed.

2. Check shading profile.

3. Check white/black reference voltage on Main PBA.

1. Room light can pass through a thin original.

2. Redo shading profile in the tech mode.

3. Replace the Main PBA.

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7.5.3 Abnormal noise

• Description There is noise from the ADF when copying.

Check and Cause Solution

1. Check the Scanner Motor, gearbox and rollers.

2. Check the Motor Driver on Driver PBA.

7.5.4 Defective Image Quality

• Description The copied image is excessively light or dark

Check and Cause Solution

1. Check shading profile.

2. Check the gap between original and scanner
glass.

3. Check printing quality.

1. Redo shading profile in the tech mode.

2. Agap of more than 0.5 mm can cause a blurred
image. Ensure rollers and cover close correctly.
Replace as necessary.

3. See "Print" troubleshooting.

1. Check for correct assembly of gears and motor.
Ensure no parts are fouling and there are no foreign
objects in the mechanism or scanner path. Replace
any worn parts

2. Replace the main PBA.

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7.6 Scanning Problems – Causes and Solutions

7.6.1 PC Scanning problems

• Description Unable to scan using a PC.

Check and Cause Solution

1. Check the Cable (USB or Parallel) is properly
connected and that the printer can print correctly.

2. Check that the driver is installed properly.

3. Check that the copy function operates normally.

1. Reconnect the PC and printer, replace any faulty
cables. If using a parallel cable, check that the par­allel port is properly configured in the BIOS.

2. If printing is OK check that the Scan driver is also
installed (Refer to User's Manual.)

3. If the copy function works, replace the Main PBA.
If the copy function doesn't work, replace the CCD
Ass'y and try again.

7.6.2 Poor Quality of PC Scanned images

• Description The image PC scanned is not clear or bad.

Check and Cause Solution

1. Use TECH mode to carry out a shading test (see
page 6.15) and examine the waveform printout.

2. Check if the resolution is set too low in PC Scan
options. (Refer to User's Manual.)

1. If the CCD waveform form is abnormal replace the
CCD Ass'y .

2. Teach the user about scanner resolution – refer to
the User Guide.

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7.7 Toner Cartridge Service

Only toner cartridges supplied by Samsung should be used. Printing defects or set damage caused by the use of
non-approved toner cartridges or un-licensed toner refills are not covered by the guarantee.

7.7.1 Precautions on Safe-keeping of Toner Cartridge

Excessive exposure to direct light for more than a few minutes may cause damage to the cartridge.

7.7.2 Service for the Life of Toner Cartridge

If the printed image is light due to the toner supply becoming low you can temporarily improve the print quality by
redistributing the toner (Shake the toner cartridge), however you should replace the toner cartridge to solve the problem
permanently .

7.7.2.1 Redistributing Toner

When the toner cartridge is near the end of its life, white streaks or light print occurs. The LCD displays the warning mes­sage, “Toner Low.” You can temporarily reestablish the print quality by redistributing the remaining toner in the cartridge.

1. Open the Front Cover.

2. Lightly pushing the used cartridge down, pull it out.

Note : Help the environment by recycling your used toner car-

tridge. Refer to the recycling brochure packed with the
toner cartridge for details.

3. Unpack the new toner cartridge and gently shake it hor­izontally four or five times to distribute the toner evenly
inside the cartridge.

4. Save the box and the cover for shipping. Slide the new
toner cartridge in until it locks into place.

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Samsung Electronics

7.7.3 Standard of guarantee for consumable parts.

Please refer to User's Manual or Instructions on Fax/Printer Consumables SVC manual for the criteria for judging the
quality of consumable parts the standard of guarantee on those parts.

• Spotting a refilled cartridge by eye.

One way security screws are used in the manufacture of the cartridge – check if these are damaged.

7.7.4 Error messages in the LCD window related to toner.

This section explains messages on the LCD that are related to the data stored in the EEPROM in the toner cartridge.

7.7.4.1 Toner Low

- Explanation: The amount of toner remaining is less than 10%

- Solution: The cartridge is almost empty or life-expired – replace the cartridge.

7.7.4.2 Toner Empty

- Explanation: The toner cartridge is empty

- Solution: Replace the cartridge.

7.7.4.3 Drum Warning

- Explanation: This message appears when the OPC drum is nearing the end of its life (14,000pages). This means
that the life of the mechanical parts in the cartridge has expired (this is not an indication of toner remaining).

- Solution: After printing about 15,000 pages, in a worst case scenario, the waste toner collector might overflow and it
may cause the system to fail. Also after 15,000 pages the OPC drum surface will be becoming worn and print quality
will degrade, print images will become misty. It is therefore necessary to replace the cartridge even though there may
be toner left in it.
When this message occurs there are approximately 1,000 pages left.

7.7.4.4 Replace Drum

- Explanation: The toner cartridge mechanical life is expired.

- Solution: Replace the cartridge.

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7.7.5 Signs and Measures of Poor toner cartridge

Fault Signs Cause & Check Solution

Light image and
partially blank
image
(Cartridge life is
ended.)

T oner
Contamination

• The printed image
is light or dirty and
untidy .

• Parts of the image
are not printed.

• Periodically a "tick
tick" noise occurs.

• Toner
contamination of
the printed page at
regular intervals
down the page.

• Random Toner
contamination over
the whole or large
parts of the paper
surface.

1. If the image is light or dirty
and untidy - Shake the toner
cartridge and then recheck.
OK: Lack of toner, so the life
is nearly expired.

2. Some part of image is not
printed - Shake the toner
cartridge and then recheck.
(1)NG: clean the LSU window
with a cotton swab, then
recheck.
(2)OK: Lack of toner, so the
life is nearly closed.

3. Periodically a noise like "tick
tick" occurs - Measure the
time between ticks.

4. White vertical stripes on the
whole or part of the page :
Shake the toner cartridge and
then recheck. OK: Lack of
toner, so the life is nearly
expired

1. Contamination at regular
intervals.
(a)Check the distance
between contamination
marks.
(b)Check the appearance of
both ends of the toner
cartridge OPC drum.

2. Random page contamination.
(a) Check that the terminals
(contact points) of the toner
cartridge and the set are
clean.
(b) Check that the terminals
(contact points) of the toner
cartridge and the set are not
damaged.

1. All of 1, 2, 3
If image quality improves by
shaking, replace with a new
toner cartridge. Perhaps up to
100 pages left before out of
toner.

2. For item 2­If image quality improves after
cleaning the LSU window then
the toner cartridge is normal.
(Contamination on the LSU
window has caused image
quality problems.)

3. For item 3­If the time between ticks is
about 2 seconds, the toner
inside the toner cartridge is
almost exhausted.
( Purchase and replace with a
new toner cartridge. Perhaps up
to 200 pages left before out of
toner)

4. For item 3­This is a phenomenon caused
by lack of toner, so replace the
toner cartridge.

1.(a) Refer to section 7.6

1.(b) If both ends of the OPC drum

are contaminated with toner:
Check no. of pages printed using
this cartridge – perhaps waste
toner collector is full.

2. Clean all HV contacts. If the
problem persists replace the
cartridge.

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

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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

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Fault Signs Cause & Check Solution

Ghost & Image
Contamination

• The printed image
is too light or dark,
or partially
contaminated black.

• Totally
contaminated black.
(Black image
printed out)

• The density of
printouts is too dark
and ghost occurs.

1. The printed image is too light
or dark, or partially
contaminated black.

(a) Check if foreign substance

or toner are stuck to the
terminals (point of contact)
of the toner cartridge or set.

(b) Check if the terminal

assembly is normal.

2. Totally contaminated black.
(Black image printed out)
(a) Check if foreign

substances are stuck to
the terminal (point of
contact) of the toner
cartridge or set.

(b) Check if the terminal

assembly is normal.
(Especially check the
charge roller terminal.)

3. The printed image is dark and
ghost occurs.
(a) Check if foreign

substances are stuck to
the terminal (point of
contact) of the toner
cartridge or set.

(b) Check if the terminal

assembly is normal.
(Especially check the
developer roller terminal.)

1. All of Items 1, 2, 3
(a) Clean the contacts on the

toner cartridge.

(b) Clean the contact points on

the set.

(c) If the terminal assembly is

damaged repair or replace
the terminals in the set or
replace the cartridge

2. In Item 2
This is particularly related to
problems with the charge roller
contact. Pay close attention to
the charge roller contacts.

3. In Item 3
This is particularly related to
problems with the developer
bias voltage contact. Pay close
attention to the charge roller
contacts.

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7.8 Software Problems – Causes and Solutions

7.8.1 The printer is not working (1)

• Description

While Power turned on, the printer is not working in the printing mode.

Check and Cause Solution

1. Run Self-Test Mode: using the menu buttons print the
test page. (Menu, Enter, Enter).

2. Check that the PC and the printer are properly
connected and that the toner cartridge installed
correctly .

3. Printing is not working in the Windows.

4. Check that the printer cable is directly connected to the
printer.

1. If the test print works that means there are no
problems in the printer itself. If the test printing does
not work that means the printer is faulty and the
problem is not due to computer software or driver
settings.

2. Replace the printer cable. If the problem is not
solved even after the cable is replaced, check the
amount of the remaining toner. (refer to Toner
Cartridge Service 7-6, Page 7-25)

3. Check that the connection between PC and printer
port are correcct. If you use windows, check that the
printer driver in the controller is set up correctly set
up, the correct port is selected and ‘Use On-line’ is
selected in the driver. If the printer driver is properly
set up try printing a test page from the driver proper­ties. Check in which program printing is not working.
Try opening ‘Memo Pad’and printing. If the printer
is not working in a certain program, adjust the setup
within that program.
Sometimes, the printout is normal within the
Windows basic programs, but it's not working in a
particular program. In this case, uninstall and re­install the new driver. If the printer is not working in
the Windows basic programs and you are printing
using the parallel port check the port setting in
CMOS is on ECP and that the address is IRQ 7
and 378 (for parallel port 1). Try using USB instead
of parallel – or vice versa.

4. If you have other devices that need to share the
printer port try temporarily disconnecting these
devices 9and perhaps even uninstalling their dri­vers) to ensure the printer works by itself. If you are
using a USB hub try connecting directly to the back
of the PC instead.

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7.8.2 The printer is not working (2)

• Description

After receiving the print command there is no response at all or print speed is low
due to wrong setup of the environment rather than malfunction of the printer itself.

Check and Cause Solution

1. Ensure you have sufficient free hard disk space for the
temporary work files created during printing.

2. Printing error occurs even if there is enough space in
the hard disk.

3. Check the parallel-port-related items in the CMOS
Setup.

4. Reboot the system to print.

1. Not working with the message 'insufficient printer
memory' means there is a hard disk space problem
rather than a printer RAM problem. In this case pro­vide more space on the hard disk. Secure more
space using the disk utilities program.

2. The connection of the cable and printer port is not
correct. Check that the cable is properly connected
and if you are using the parallel port check that the
port settings in CMOS is correct.

3. For the printer port, Select ECP. SPP and normal
normal modes support 8-bit data transfer, while
ECP Mode supports 12-bit data transfer.

4. If the regular font is not printing, the cable or the
printer driver may be defective.
Turn the PC and printer off, and reboot the system
to print again. If not solved, double-click the printer
in my computer If the regular fonts are not printed
this time again. the cable must be defective so
replace the cable with new one.

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7.8.3 Abnormal Printing

• Description

Printing does not work – even after replacing the cable
Printer does not work at all or strange fonts are printed,

Check and Cause Solution

1. Set up the parallel port using CMOS SETUP.

2. Printer Driver Error.

3. Error message “insufficient memory”.
(The printing job sometimes stops due to insufficient
virtual memory, this is caused by insufficient space on
the hard disk.)

1. Ensure that ECP (best) or SPP is selected in the
CMOS (BIOS) setup.

2. Ensure that the correct driver is loaded. Use the
driver supplied on the CD or downloaded from the
Samsung web site. DO NOT use the Microsoft
driver supplied with the Windows operating system.
If the printer is a GDI or SPL type printer ensure that
ALL OTHER GDI or SPL drivers are uninstalled as
Windows allows only 1 of this type of driver to be
loaded.

3. Delete any unnecessary files to secure enough
space on the hard disk and start the print job again.

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7.8.4 SPOOL Error

• Description

SPOOL (simultaneous peripheral operations online) is the process Windows uses to
manage print jobs. Jobs are processed and then stored on the hard disk until the printer is
ready to accept them

Check and Cause Solution

1. Insufficient space on the hard disk in the directory
assigned for the basic spool.

2. If previous printing errors were not solved.

3. There may be conflict with other drivers or programs.

4. When an application program or the printer driver is
damaged.

5. When some files related to the OS are damaged or
virus infected.

6. Memory is less than suggested.

1. Delete any unnecessary files to provide more space
for spool storage.

2. There may be files from previous failed print jobs on
the hard disk with the name in the form ‘*.jnl’.
Delete these files and Reboot Windows to restart
the printer.

3. Shut down all other programs except the current
one, if possible.

4. Delete the printer driver completely and reinstall it.

5 After rebooting the computer, check for viruses,

restore the damaged files and reinstall the
application program which is not working properly.

6. Add up more memory to the PC.

How to delete the data in the spool manager.

In the spool manager, the installed drivers and the list of the documents waiting to be printed are shown.
Select the document to be deleted and check delete in the menu.

If the job you are deleting is the current job when you delete the job data that has already been transferred to
the printer’s memory will still be printed. If there is a problem with the printer (out of toner, offline, out of paper
etc.) the job may take a long time to delete as it must wait for a time out.

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7.9 Network Problem Troubleshooting

7.9.1 General Problems

Incorrect setup can cause network errors.

Problem Solution

Possibly the parameters in PortThru (the network card) are corrupt­ed. Restart the system and reset the printer network settings to fac­tory defaults using the printer front panel or by using SyncThru on
your computer.

SNMP Manager cannot access the printer. Using the SNMP manager computer try pinging the printer. If it

does not succeed there must be a problem with network connectivi­ty between the SNMP manager computer and PortThru. If ping suc­ceeds verify that community names entered into the PortThru set­tings are spelled correctly and have sufficient permissions.

The printer does not obtain an IP address
from a BOOTP, RARP or DHCP server.

If there is an IP address server on your network ensure that there
are no VLAN, Access Control Lists or other network settings pre­venting communication. Remember these protocols are generally
not routable unless specifically setup in a router.
Where no address server exists use SyncThru or the control panel
on the printer to select "Static" IPAddress Assignment Method" in
TCP/IP tab. You should set IP address, Subnet Mask and Default
Gateway in the printer using SyncThru, printer control panel or
browser methods (see the user guide).

Print server does not print using TCP/IP protocol. 1. Check that TCP/IP protocol is installed and properly configured in

your PC.

2. Check whether your PC is on the same network with print server
(IP addresses and subnet masks must be properly set in the PC
AND in the printer).

Unable to print in a NetWare environment. Use SyncThru to see if PortThru indicates that queue is service-

able. If not, the login permissions may have changed or the config­uration information for queues, printers and print servers may have
been changed. Verify using PCONSOLE and NWADMIN that the
configuration is correct and check the job queue to see if the print
job exists. Check that NetWare is enabled on PortThru. Check that
the Check Job very is configured on PortThru.

The name of printer is not displayed when
adding a port and the printer doesn't function.

1. Check that the protocol settings on your computer are correct.

2. Assign an IPAddress to PortThru using the front panel,
SyncThru or browser methods (see the user guide).

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7.9.2 Windows Problems

After installing PortThru the print server name
is not displayed under New Print Server in
SyncThru.

Problem Solution

1. Verify that the printer power switch is turned on and the 'READY'
message is displayed on the printer front panel.

2. Verify that the LAN cable is plugged into the PortThru card.

3. There are 2LEDs on the PortThru card. One should flash irregularly
and the other should be on. If this is not the case ensure that the
network card is properly installed and the PCB an cable connectors
make a good connection. If the problem continues check the network
cable / socket by using a different cable or socket. If the problem
continues replace the network card.

4. Confirm that the print server and the PC which searches for the
New Print Server is on the same LAN (correct IP and subnet
mask settings). If you want to search for a New Print Server your
PC and the print server should be on the same LAN.

The print server name is displayed, but the test
page is not printed.

Using the front panel menus print the Network configuration. If the
Network menu is not displayed or the configuration page is not
printed turn off the printer, ensure the network card is properly fitted
then turn it back on and try again. If the problem continues replace
the network card.

SyncThru indicates that firmware upgrade is
complete but when the network configuration
is printed the software version has not changed.

Before attempting to upgrade firmware ensure that computer and
printer can communicate using a Ping command.

SycThru is unable to automatically detect
the printer.

1. Check that the LAN cable is connected to the printers. If an IP
address is assigned to the computer and printer ensure that the
Ping command can see the printer.
If an IP address is not allocated to the printer or it is in a different
LAN segment then ensure that either IPX/SPX or DLC/LLC pro­tocols are enabled on the computer.

2. Print the network configuration. If the TCP/IP or Network proto­cols are disabled in the printer either use the front panel to re­enable them or ensure that DLC/LLC protocol is installed in the
computer.

3. In SyncThru use the Settings / Protocol Selection menu option to
select either TCP/IP or IPX protocols and then use the
View/Refresh option to scan the network again.

4. Ensure that the network cable and wall socket are functioning
correctly .

5. Ensure that the version of SyncThru is the same as or newer
than the version supplied with the printer.

6. Ensure that there is no router between the printer and the
computer as SyncThru will not work through a router.

7. Ensure there are no Switch or Router VLAN or Access Control
Lists which are blocking communication between the printer and
the computer.

Note Windows XP does not support DLC/LLC protocols.

The printer does not print via a
network connection.

1. Connect the printer using a Parallel or USB cable and ensure
that the computer can print. If not check that the printer drivers
are installed correctly

2. If the printer can print via a local connection check Printer
Properties / Ports and ensure that a TCP/Ip port has been allo­cated to the printer.

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7.9.3 SyncThru Installation Problems

"File Transfer Error" message appears during
the Installation process.

Problem Solution

1. Make sure that any previously installed version of SyncThru is
uninstalled. Restart your PC after uninstalling previous versions.

2. If the problem continues, In Windows 95/98 boot into MS/DOS
mode and delete the "sammon.dll" file in the windows\system
directory the restart Windows and reinstall SyncThru. In Windows
NT stop the spooler service using' Services 'in Control Panel,
delete the "sammon.dll" file in the windows\system32 directory
then restart the spooler service and reinstall SyncThru.

'Unable to add the Port list of Samsung ports'
message appears when you add a port.

Verify that your PC restarts after installing SyncThru.