Samsung ML-1700 User Manual

SERVICE

LASER PRINTER
ML-1700 Series

ML-1710
ML-1750

Manual

LASER PRINTER CONTENTS

1. Precautions

2. Reference Information

3. Specifications

4. Summary of product

5. Disassembly and Reassembly

6. Alignment and Adjustments

7. Troubleshooting

8. Exploded Views and Parts List

9. Block Diagram

10. Connection Diagram

© Samsung Electronics Co.,Ltd. February 2003

Printed in Korea.

VERSION NO. : 1.00 CODE : JC-0093A

This service manual is also provided on the web,
the ITSELF system f Samsung Electronics Co., Ltd.

http://itself.sec.samsung.co.kr

ELECTRONICS

2003. 02

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Samsung Electronics

Precautions

Service Manual

1. Precautions

The cautions in the below are items needed to keep in mind when maintaining and servicing.
Please read carefully and keep the contents in mind to prevent accidents while servicing and to prevent
that the machine gets damage.

1.1 Warning for safety.

(1) Request the service by qualified service person.
The service for this machine must be performed by a service person who took the additional education of
this field.
It is dangerous if unqualified service person or user tries to fix the machine.

(2) Do not rebuild it discretionary.
Do not attach or change pats discretionary. Do not dissemble, fix, and rebuilt it. If do, printer will abnormally
work and electric shock or a fire can be occurred.

(3) Laser Safety Statement
The Printer is certified in the U.S. to conform to the requirements of DHHS 21 CFR, chapter 1 Subchapter J
for Class 1(1) laser products, and elsewhere, is certified as a Class I laser product conforming to the
requirements of IEC 825.
Class I laser products are not considered to be hazardous. The laser system and printer are designed so
there is never any human access to laser radiation above a Class I level during normal operation, user
maintenance, or prescribed service condition.

Warning >> Never operate or service the printer with the protective cover removed from Laser/Scanner assembly. The reflected

beam, although invisible, can damage your eyes. When using this product, these basic safety precautions should
always be followed to reduce risk of fire, electric shock, and injury to persons.

CAUTION - INVISIBLE LASER RADIATION

WHEN THIS COVER OPEN.
DO NOT OPEN THIS COVER.

VORSICHT - UNSICHTBARE LASERSTRAHLUNG,

WENN ABDECKUNG GE FFNET.
NICHT DEM STRAHL AUSSETZEN.

ATTENTION - RAYONNEMENT LASER INVISIBLE EN CAS

D OUVERTURE. EXPOSITION DANGEREUSE
AU FAISCEAU.

ATTENZIONE - RADIAZIONE LASER INVISIBILE IN CASO DI

APERTURA. EVITARE LESPOSIZIONE AL
FASCIO.

PRECAUCION - RADIACION LASER IVISIBLE CUANDO SE ABRE.

EVITAR EXPONERSE AL RAYO.

ADVARSEL. - USYNLIG LASERSTR LNING VED BNING, N R

SIKKERHEDSBRYDERE ER UDE AF FUNKTION.
UNDG UDSAETTELSE FOR STR LNING.

ADVARSEL. - USYNLIG LASERSTR LNING N R DEKSEL

PNES. STIRR IKKE INN I STR LEN.

UNNG EKSPONERING FOR STR LEN.

VARNING - OSYNLIG LASERSTR LNING N R DENNA DEL

R PPNAD OCH SP RREN R URKOPPLAD.

BETRAKTA EJ STR LEN. STR LEN R FARLIG.

VARO! - AVATTAESSA JA SUOJALUKITUS OHITETTAESSA

OLET ALTTIINA N KYM TT M LLE LASER­S TEILYLLE L KATSO S TEESEEN.

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Precautions

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Service Manual

1.2 Caution for safety

1.2.1 Precaution related noxious material

The toner in a printer cartridge contains a chemical material, which might harm human body if it is swallowed.
Please keep children out of the toner cartridge.

1.2.2 Precaution related electric shock or fire

It is possible to get electric shock or burn by fire if you don't fallow the instructions of the manual.

(1) Use exact voltage. Please do use an exact voltage and wall socket. If not, a fire or an electric leakage can

be caused.

(2) Use authorized power code. Do use the power code supplied with PRINTER. Afire can be occurred when

over current flows in the power code.
(3) Do not insert many codes in an outlet. If do, a fire can be occurred due to flow over current in an outlet.
(4) Do not put water or extraneous matter in the PRINTER. Please do not put water, other liquid, pin, clip, etc.

It can cause a fire, electric shock, or malfunction. If it is happened, turn off the power and remove the

power plug from outlet immediately.
(5) Do not touch the power plug with wet hand. When servicing, do remove the power plug from outlet. And

do not insert or take off it with wet hand. Electric shock can be occurred.
(6) Caution when inserting or taking off the power plug. The power plug has to be inserted completely. If not,

a fire can be caused due to poor contact. When taking off the power plug, do grip the plug and take it off.

If grip the line and pull over, it could be damaged. A fire or electric shock could cause.
(7) Management of power code. Do not bend, twist, or bind it and place other materials on it. Also, do not fix

it with staples. If the power code gets damage, a fire or electric shock can be caused. Adamaged power

code must be replaced immediately . Do not repair the damaged part and reuse it. Arepaired part with plas-

tic tape can be occurred a fire or electric shock. Do not spread chemicals on the power code. Do not

spread insecticide on the power code. Afire or electric shock can be occurred due to thinner(weak) cover

of the power code.
(8) Check whether the power outlet and the power plug are damaged, pressed, chopped, or blazing fire or

not. When such inferiorities are found, repair it immediately. Do not make it pressed or chopped when

moving the machine.
(9) Caution when thundering, and being flash of lightening. It causes a fire or electric shock. Take the power

plug off when thundering. Do not touch cable and device when thundering and being flash of lightening.
(10) Do avoid the place where is moisture or has dust. Do not install the printer in where have lots of dust or

around humidifier. A fire can be occurred. Aplug part need to clean well with dried fabric to remove dust.
If water drops are dripped on the place covered with dust, a fire can be occurred.

(11) Avoid direct sunlight. Do not install the printer near to window where directly contacts to the sunlight. If

the machine contacts sunlight long time, the machine cannot work properly because inner temperature
of the machine is getting higher. A fire can be caused.

(12) Turn off the power and take off the plug when a smoke, strange smell, or sound from the machine. If you

keep using it, a fire can be occurred.

(13) Do not insert steel or metal piece inside/outside of the machine. Do not put steel or metal piece into a

ventilator. An electric shock could be happened.

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Precautions

Service Manual

1.2.3 Precaution related handling the machine.

If you ignore this information, you could get harm and machine could be damaged.

(1) Do not install it on the different levels, or slanted floor.

Please confirm whether it is balanced or not after installation. If it is unbalanced, an accident can be hap­pened due to the machine fell over.

(2) Be careful not to insert a finger or hair in the rotating unit.

Be careful not to insert a finger of hair in the rotating unit (motor, fan, paper feeding part, etc) while the
machine is operating. Once it happens, you could harm.

(3) Do not place a pot contains water/chemical or small metals. If those are got into the inner side of machine,

a fire or electric shock can be occurred.

(4) Do not install it in where lots of moisture or dust exists or where raindrop reaches. Afire or electric shock

can be caused.

(5) Do not place a candlelight, burning cigarette, and etc. on the machine. Do not install it near to heater. A

fire can be occurred.

1.2.4 Precaution when assembly/disassembly

When replace parts, do it very carefully. Do memorize the location of each cable before replace parts for
reconnecting it afterwards. Do memorize. Please perform the below before replace or disassembly the parts.

(1) Check the contents stored in the memory. All the information will be erased after replace main board. The

information needed to keep has to be written down.
(2) Before servicing or replacing electric parts, take off a plug.
(3) Take off printer cables and power code connected to printer.
(4) Do use formal parts and same standardized goods when replacing parts.Must check the product name,

part code, rated voltage, rated current, operating temperature, etc.
(5) Do not give an over-force when release or tighten up the plastic parts.
(6) Be careful not to drop the small parts such as screws in the printer.
(7) Be careful not to change the location of small parts such as screws when assembling and disassembling.
(8) Do remove dust or foreign matters completely to prevent fire of tracking, short, or etc.
(9) After finished repair, check the assembling state whether it is same as before the repair or not.

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Precautions

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Service Manual

1.3 ESD Precautions

Certain semiconductor devices can be easily damaged by static electricity. Such components are commonly
called “Electrostatically Sensitive (ES) Devices”, or ESDs. Examples of typical ESDs are: integrated circuits,
some field effect transistors, and semiconductor “chip” components.
The techniques outlined below should be followed to help reduce the incidence of component damage caused
by static electricity.

Caution >>Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.

1. Immediately before handling a semiconductor component or semiconductor-equipped assembly, drain off
any electrostatic charge on your body by touching a known earth ground. Alternatively, employ a commer­cially available wrist strap device, which should be removed for your personal safety reasons prior to apply­ing power to the unit under test.

2. After removing an electrical assembly equipped with ESDs, place the assembly on a conductive surface,
such as aluminum or copper foil, or conductive foam, to prevent electrostatic charge buildup in the vicinity
of the assembly.

3. Use only a grounded tip soldering iron to solder or desolder ESDs.

4. Use only an “anti-static” solder removal device. Some solder removal devices not classified as “anti-static”
can generate electrical charges sufficient to damage ESDs.

5. Do not use Freon-propelled chemicals. When sprayed, these can generate electrical charges sufficient to
damage ESDs.

6. Do not remove a replacement ESD from its protective packaging until immediately before installing it. Most
replacement ESDs are packaged with all leads shorted together by conductive foam, aluminum foil, or a
comparable conductive material.

7. Immediately before removing the protective shorting material from the leads of a replacement ESD, touch
the protective material to the chassis or circuit assembly into which the device will be installed.

8. Maintain continuous electrical contact between the ESD and the assembly into which it will be installed,
until completely plugged or soldered into the circuit.

9. Minimize bodily motions when handling unpackaged replacement ESDs. Normal motions, such as the
brushing together of clothing fabric and lifting one’s foot from a carpeted floor, can generate static electric­ity sufficient to damage an ESD.

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REFERENCE INFORMATION

Service Manual

2. Reference Information

This chapter describes the reference information for applying this training manual, and it is consist­ed of the tool list, the abbreviation table, the outline of model, and so on.

2.1 Tool for Troubleshooting

The following tools are recommended for safe and smooth troubleshooting described in this service manual.

DCU(Diagnostic Control Unit)

Standard : Test equipment to diagnose the Laser
printer supplied by Samsung Electronics.

1

Driver

Standard : "-" type, "+" type (M3 long, M3 short, M2 long,

M2 short).

4

Cotton Swab

Standard : For general home use, for medical ser-vice

6

Software(Driver) installation CD ROM

8

Cleaning Equipments a IPA(Isopropyl
Alcohol)dry cloth or a soft stuff neutral
detergent

7

T weezers

Standard : For general home use, small type.

5

DVM(Digital Volt Meter)

Standard : Indicates more than 3 digits.

2

Electronic Scale

Standard : Equipment to check the weight of con­sumables(toner cartridge) supplied by Samsung
Electronics. (The gram unit can be measured.)

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Service Manual

2.2 Acronyms and Abbreviations

The table in the below explains abbreviations used in this service manual.
The contents of this service manual are declared with abbreviations in many parts. Please refer to the
table.

AC Alternating Current
ASIC Application Specific Integrated Circuit
ASSY assembly
BIOS Basic Input Output System
CMOS Complementary Metal Oxide

Semiconductor
CN connector
CON connector
CPU Central Processing Unit
dB decibel
dbA decibelampere
dBM decibel milliwatt
DC direct current
DCU Diagnostic Control Unit
DPI Dot Per Inch
DRAM Dynamic Random Access Memory
DVM Digital Voltmeter
ECP Enhanced Capability Port
EEPROM Electronically Erasable Programmable

Read Only Memory
EMI Electro Magnetic Interference
EP electrophotographic
EPP Enhanced Parallel Port
F/W firmware
GDI graphics device interface
GND ground
HBP Host Based Printing
HDD Hard Disk Drive
HV high voltage
HVPS High Voltage Power Supply
I/F interface
I/O Input and Output
IC integrated circuit
IDE Intelligent Drive electronics or Imbedded

Drive Electronics

IEEE Institute of Electrical and Electronics

Engineers. Inc
IPA Isopropy Alcohol
IPM Images Per Minute
LAN local area network
lb pound(s)
LBP Laser Beam Printer
LCD Liquid Crystal Display
LED Light Emitting Diode
LSU Laser Scanning Unit
MB megabyte
MHz megahertz
NVRAM nonvolatile random access memory
OPC Organic Photo Conductor
PBA Printed Board Assembly
PCL Printer Command Language , Printer

Control Language
PDL Page Discription Language
PPM Page Per Minute
PTL Pre-Transfer Lamp
Q-PID Quick Printer Initiating Device
Q ty quantity
RAM Random Access Memory
ROM Read Only Memory
SCF Second Cassette Feeder
SMPS Switching Mode Power Supply
SPGP Samsung Printer Graphic Processor
SPL Samsung Printer Language
Spool Simultaneous Peripheral Operation Online
SW switch
sync synchronous or synchronization
USB Universal Serial Bus

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REFERENCE INFORMATION

Service Manual

2.3 The Sample Pattern for the Test

The sample pattern shown in below is the standard pattern used in a factory.
The contents of the life span and the printing speed are measured with the pattern shown in below.
(The picture in the manual is 70% size of the actual A4 size.)

2.3.1 A4 5% Pattern

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Service Manual

2.3.2 A4 2% Pattern

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REFERENCE INFORMATION

Service Manual

2.3.3 A4 IDC Pattern

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Service Manual

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Specifications

Service Manual

3. Specifications

Product specifications are subject to change without notice.See below for product specifications.

3.1 General Specifications

ITEM DESCRIPTION

Print Technology Non-impact Electro-photograpic Printing
Developing system Non-Magnetic, Mono-Component Developing System
Print Speed

(1)

16 PPM : A4 size , 5% Character pattern
17 PPM : Letter size , 5% Character pattern

Resolution ML-1710 : True 600 X 600 DPI

ML-1750 : 1200 X 600 DPI
Source of Light Laser diode (LSU : Laser Scanner Unit)
Warm-Up Time Power-on boot : 30 seconds or less
First Print Out Time Less than 12 seconds (Ready to 1st page out)
Media Size 75 X 125 (3” X 5”) mm to 216 X 356 (8.5” X 14”)mm
Media Thickness 16 ~ 24 lb
Dimension(W X D X H) 352 (13.8”) X 372 (14.6”) X 196 (7.7”) mm
Weight Net : 7 Kg /15.4 lb

Gross : 9.5 Kg (Max.)
Acoustic Noise

(1)

Stand by : Less than 35 dB

Printing : Less than 50 dB
Power save mode Available

Toner save mode Available
Duty Cycle Monthly : 15,000 pages maximum
Periodic Replacing Parts

(2)

Pick Up Roller : 60,000 Sheets

Feed Roller : 60,000 Sheets

Transfer Roller : 60,000 Sheets

Fuser Assembly : 60,000 Sheets

(1) For measuring the printing speed, count the papers which outputted within one minute from when the

second page starts to be printed. (A4, 5% character pattern standard)

(2) The life span of the consumption parts can be checked by printing the demo page or the system list.

(Refer to the 6.3 Receive the service information)

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Specifications

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Service Manual

3.3 Electrical Specification

3.2 Controller Specification

ITEM

DESCRIPTION

ML-1710 ML-1750

Processor(CPU) Samsung Jupiter4 90MHz Samsung SPGPm 166MHz
OS Compatibility

(1)

Win 98x/ME/2000/XP, Win 9x/NT4.0/ME/2000/XP
Various Linux OS,Mac (Mac OS 8.6

↑) Various Linux OS,Mac (Mac OS 8.6 ↑)

Memory FLASH ROM(PROGRAM) : 0.5MB flash

RAM : 8 MB

EEPROM(NVRAM) : 512 byte
Emulation SPL(Samsung Printer Language) PCL6, IBMProPrinter, EPSON
Interface USB 1.1 USB

- 12 Mbps 1 port - USB 2.0

- 480 Mbps 1 port

Parallel : IEEE 1284

- Modes supported :
Compatible,Nibble,Byte,ECP
External Network Adaptor(Optional)

Interface switching Automatic
Interface time-out 5min(Max.)
Font Windows Font 45 Scalable, 1 Bitmap

ITEM DESCRIPTION

Input Voltage Nominal input voltage 100~127VAC

Input voltage range 90~132VAC
Nominal frequency 50/60 Hz
Frequency tolerance +3Hz

Power Consumption Printing : 280W Avg or less Power Save : 10W Avg or less

3-4 Environmental Range

ITEM OPERA TING STORAGE

Temperature 10~32 oC(50-90 oF) -20~40 oC (-4~104 oF)
Humidity 20~80%RH 10~80%RH

(1)

The SPL series model is USB exclusive use, so it supports the environment beyond the WIN 98.

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Specifications

Service Manual

• Input capacity

Cassette: 250 sheets
Manual : 1 sheet

• Output capacity

Face Down : 50 sheets(20lb)
Face Up : 1 sheet(OHP, Lavbel, Cut Sheet, Envelope)

2-Paper Handling Specifications

Please refer to "Paper Specifications" on user guide

• Input Paper Size

3.5 TONER Cartridge (Developer)

ITEM DESCRIPTION REMARK

Life span Starter: 1,000 sheets IDC 5% pattern

Running : 3,000 sheets
Developing Non-magnetic Mono Conponent Contact Developing
Charging Conductive Roller Charging
Toner checking sensor Not Available
Ozone 0.1PPM or less 8 hours
Style Single cartridge

P APER DIMENSIONS WEIGHT

A4 210 X 297 mm 60 to 90 g/m2 bond(16 to 24 lb)
Letter 216 X 279(8.5 X 11")
Legal(Legal14") 216 X 356(8.5 X14")
JIS B5 182 X257mm (7.2 X 10")
Folio(Legal13") 216 X 330mm (8.5 X 13")

Minimum size (Custom) 76 X 127mm (3 X 5") 60 to 163 g/m2bond(16 to 43 lb)
Maximum size (Custom) 216 X 356mm (8.5 X 14")
Transparency(OHP) Same minimum and maximum Thickness:
Label paper sizes as listed above 0.10 X 0.14 mm (0.0039 X 0.0055")

Envelopes Up to 90 g/m2 bond(16 to 24 lb)

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Service Manual

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SUMMARY OF PRODUCT

Service Manual

4. Summary of Product

This chapter describes the functions and operating principal of the main component.

4.1 Printer Components

4.1.1 Front View

Output Support

Top output tray
(Face down)

Control Panel

Power switch

Paper level indicator

Tray

Manual Feeder

Manual Feeder guide

Front Cover

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Service Manual

4.1.2 Rear View

Rear output tray
(Face up)

Power receptacle

Parallel port

(ML-1750 Only)

USB port

4.1.3 Inside View

Toner cartridge

Front Cover

LED Description

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SUMMARY OF PRODUCT

Service Manual

4.1.3 Control Panel

1) On Line/Error and Toner Save LEDs

If the On Line/Error lights green, the printer is ready to print.
If the On Line/Error lights red, the printer is experiencing an error, such as jammed paper,

the open cover or the empty toner cartridge. If you press the Cancel button while the printer
is receiving data, the On Line/Error LED blinks red to cancel printing.

In Manual Feed mode, if there is no paper in the Manual Feeder, the On Line/Error LED
blinks red. Load paper into the Manual Feeder and the LED stops blinking.

If the printer is receiving data, the On Line/Error LED slowly blinks green.
If the printer is printing the received data, the On Line/Error LED blinks green fast.

If you press the Cancel button in Ready mode, this LED is on and the Toner Save mode is
enabled.
If you press this button once again, this LED is off and the Toner Save mode is disabled.

If the On Line/Error and Toner Save LEDs blink, your system has some problems. To solve
the problem.

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2) Cancel button

Printing demo page In Ready mode, press and hold this button for about 2 seconds until

all LEDs blink slowly, and release.

Printing configuration sheet In Ready mode, press and hold this button for about 6 seconds until

all LEDs blink fast, and release.

Manual feeding Press this button each time you load a sheet of paper in the manual

feeder, when you select Manual Feed for Source from your software
application.

Cleaning inside printer In Ready mode, press and hold this button for about 10 seconds

until all LEDs turn on, and release. After cleaning the printer, one
cleaning sheet prints.

Canceling print job Press this button during printing. The On Line/Error LED blinks while

the print job is cleared from both the printer and the computer, and
then return to Ready mode. This may take some time depending on
the size of the print job.
In Manual Feed mode, you can’t cancel the print job by pressing this
button.

Toner Save mode on/off In Ready mode, press this button to turn the Toner Save mode on or

off.

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SUMMARY OF PRODUCT

Service Manual

4.2 System Layout

PTL

P

I

C

K

/

R

PR

CR

DR

SR

TR FR

OPC

L S U

Fuser

Toner Cartridge

1

1

2

2

3

6

3

4

Cassette

Manual Feeder

Transfer Roller

PTL(Per-Tramsfer-Lamp)

5

7

6
7

5

Fuser

LSU(Laser Scan Unit)

Toner Cartridge

4

MP Sensor

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Service Manual

4.2.1 Feeding Part

There are the universal cassette, which loads papers, and the manual feeder, which supplies paper one by
one. The cassette has the function pad which separates paper one by one, and it has the sensor function
to check the existence of the loading paper.

- Feeding Method: Universal Cassette Type

- Feeding Standard: Center Loading

- Feeding Capacity: Cassette-250 sheets (75g/m©˜, 20lb paper standard)
Manual 1 sheet (Paper, OHP, Envelop, etc.)

- Paper detecting sensor: Photo sensor

- Paper size sensor: None

4.2.2 Transfer Ass’y

It is consisted of the PTL (pre-transfer lamp) and the Transfer Roller. The PTL sends a light to the OPC
drum, makes the current on the drum surface to low, and improves the transfer efficiency.
The transfer roller delivers the toner of the OPC drum to the paper.

- The life span: Print over 60,000 sheets (in 15~30°C)

4.2.3 Driver Ass’y

It is a power delivery unit by gearing. By driving the motor, it supplies the power to the feeding unit, the
fusing unit, and the distributing unit.

4.2.4 Fixing Part(Fuser)

- The fuser is consisted of the Heat Lamp, Heat Roller, Pressure Roller, Thermistor, and Thermostat. It
adheres the toner to the paper with a pressure and a heat to complete the printing job.

- There are two methods, the existing method which use the Heat Lamp and the Q-PID which is developed
by Samsung.

110V : Heat Lamp type Fuser
220V : Heat Lamp type or Q-PID type Fuser

4.2.4.1 Temperature-Intercepting Device (Thermostat)

The thermostat is the temperature-intercepting device, which cuts off the power for preventing an overheat­ing or a fire when the heat lamp or the heat coil of the heat roller is overheated.

4.2.4.2 Temperature Detecting Sensor (Thermistor)

The Thermistor detects the surface temperature of the heat roller, and it maintains the regular temperature
of the heat roller by responding to the information of the temperature.

4.2.4.3 Heat Roller

The heat roller transfers the temperature from the heat lamp or heat coil to the surface to heat the paper
which passes the surface. The melted toner cannot stain the heat roller coated with Teflon.
The heating elements are heat lamp and heat coil. For this product, Q-PID method with the heat coil is
applied.

4.2.4.4 Pressure roller

The pressure roller mounted right under the heat roller is made of the silicon resin, and the surface of the
roller is coated with Teflon to fuse the toner on the paper when paper passes between the heat roller and
the pressure roller.

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SUMMARY OF PRODUCT

Service Manual

4.2.4.5 Safety Relevant Facts

• Protecting device when overheating

- 1st protecting device: H/W cuts off when detecting an overheating

- 2nd protecting device: S/W cuts off when detecting an overheating

- 3rd protecting device: Thermostat cuts off the power

• Safety device

- The power of the fuser is cut off when the front cover is open.

- The overheating safety device for customer

- Maintains the surface temperature of the Fuser Cover under 80°C and attach the caution label
inside of the rear cover where customer can find easily.

4.2.5 LSU (Laser Scanner Unit)

The LSU unit is controlled by the video controller. It scans the video data received from video controller with
laser beam by using the rotation principal of the polygon mirror to create the latent image on the OPC drum.
It is the core part of LBP.
The OPC drum rotates as the same speed as the paper feeding speed. It creates the /HS YNC signal and
sends it to the engine when the laser bean of the LSU reaches the end of the polygon mirror, and the engine
detects the /HS YNC signal to arrange the vertical line of the image on the paper. After detecting the /HS
YNC signal, the image data is sent to the LSU to arrange the its left margin on the paper.
The one side of the polygon mirror is one line for scanning.

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SUMMARY OF PRODUCT

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Service Manual

4.2.6 Toner Cartridge

By using the electronic photo process, it creates a visual image. In the toner cartridge, the OPC unit and
the developer unit are in a body. The OPC unit has OPC drum and charging roller, and the developer unit
has toner, toner cartridge, supply roller, developing roller, and blade (Doctor blade)

- Developing Method: Non magnetic 1 element contacting method

- Toner: Non magnetic 1 element shatter type toner

- The life span of toner: 3,000 sheets (IDC Pattern/A4 standard)

- Toner remaining amount detecting sensor: None

- OPC Cleaning: Collect the toner by using electric static + FILM OPC

- Management of disusable toner: Collect the toner by using electric static (Clenerless Type- No
disusable toner)

- OPC Drum protecting Shutter: None

- Classifying device for toner cartridge: ID is classified by interruption of the frame channel.

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SUMMARY OF PRODUCT

Service Manual

4.3 Main PBA(SPL Model)

The Engine Board and the Controller Board are in one united board, and it is consisted of CPU part and
print part in functional aspect. The CPU is functioned as the bus control, I/O handling, drivers, and PC inter­face. The main board sends the Current Image dlml Video data to the LSU and manages the conduct of
Electrophotography for printing. It is consisted of the circuits of the motor (paper feed, pass)
driving, clutch driving, pre-transfer lamp driving, current driving, and fan driving.
The signals from the paper feed jam sensor and paper empty sensor are directly inputted to the main
board.

USB PORT

ASIC SDRAM

FLASH MEMORY

MOTOR Drive IC

BUFFER

VIDEO CLK

14.7456MHz

Main CLK
10MHz

CN5 U25U31U20 CN8 CN7

CN6

U13

CN10

CN9

U27 U16 U26 U32 U24 CN3

OSC1

U33

OSC2

U17

CN2

CN1

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Service Manual

4.3.1 ASIC (Jupiter IV)

The Jupiter IV (16Bit RISC Processor), which is the executive controller to operate the printer function, is in
use, and the each operation block is driven by system program of the flash memory. The whole system is
controlled by driving operation block.

•Main function block

• Completely Integrated System for Embedded Applications,

• 16 Bit Risc Architecture, Efficient and Powerful ARM7TDMI CPU

• LSU Interface Module for Interfacing PVC or HPVC with LSU

• 2 Channel General Purpose DMA Controller for High Speed I/O

• Dual Memory Bus Architecture

• Operating frequency : 80MHz

• Operating power : 3.3V

• Power on reset time : under 6.6ms

4.3.2 Flash Memory

It stores the system program and downloads the system program through the PC interface.

• Capacity : 0.5M Byte

• Access Time : 70 nsec

4.3.3 SDRAM

It is used as a swath buffer, system working memory area, etc. while printing.

• Capacity :

•

Access Time : 60 nsec

4.3.4 Sensor input circuit

1) Paper Empty Sensing

The Paper empty sensor (Photo Interrupter) on the engine board informs the state of paper to CPU whether
it is empty or not with operation of the actuator.
When cassette is empty, it detects the fact by reading the D0 Bit of CPU, and then informs the fact by
selecting the second LED(yellow) among the panel LEDs.

2) MP Sensing

By operation of Actuator on the frame, the MP Sensor (Photo Interrupter) on the engine board informs the
state of paper to CPU whether it is empty or not. It reads the D0 Bit of CPU for recognizing paper in MP,
and paper is fed from MP if there is.

ML-1510 ML-1710 ML-1750

2 M byte 8 M byte 8 M byte

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SUMMARY OF PRODUCT

Service Manual

3) Paper Feeding, Toner Cartridge Sensing

When paper passes the actuator (feed sensor part), it detects the signal of Photo interrupter, informs the
paper feeding state to CPU, and then sprays the image data after certain time.
If it doesn't detect the feed sensor within 1 sec. after paper is fed, paper Jam0 is occurred (Red and Yellow
will be turned on among the OP panel LEDs), and the fact whether the developer is inserted or not is detect­ed with the same principle. After the developer is mounted, the actuator is operated. The signal from the photo
interrupter is detected when it is passing the actuator of the sensor part. That is the developer ID sensing.

4) Paper Exit Sensing

It detects paper state whether paper gets out from the set with operation of exit sensor on the engine board
and actuator on the frame. Paper detects the on/off time of exit sensor , and the normal operation or jam infor­mation is informed to the CPU.
The paper JAM2 is informed. (Red, Yellow LED will be turned on among the OP panel LEDs)

5) Cover Open Sensing

The Cover open sensor is located on the front cover. After the front cover is opened, +24V (DC fan, solenoid,
main motor, polygon motor part of LSU, HVPS), which is supplied to the each unit, is cut off.
The cover-open sensing is operated by the D0 bit of CPU, and the developer ID sensing is operated.
In this case, the red LED among OP panel LEDs will be ON for informing the facts to user.

6) DC FAN / SOLENOID Driving

It is driven by transistor and controlled by D6 bit of CPU.
When it is high, the fan is driving by turning on the TR, and it is off when the sleep mode is selected.
There are two solenoids, and they are driven by paper pick-up and MP signal. Its driving time is 300ms. The
diode protects the driving TR from the noise pulse, which is flown when the solenoid is de-energizing.

7) Motor Driving

The motor driving circuit is formed when the Driver IC is selected in the first place. The A3977 (Motor driver
IC) is used in this case. But, the resistance Rs value of sensing and the voltage value of the V reference can
be changed by motor driving voltage value.

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SUMMARY OF PRODUCT

Samsung Electronics

Service Manual

4.4 Main PBA (PCL Model)

CPU(SPGPm)

SCHMITT INVERT

IC-VOLTAGE COMP

BUFFER

SDRAM

FONT ROM

REGULATOR

CLOCK GENERATOR

MOTOR DRIVE IC

VIDEO CLK

14.7456MHz

USB CLK 30MHz

IC-USC

RC-NETWORK

IC-LINE TRANSCEVIER

MAIN CLK

12MHz

FLASH

MEMORY

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SUMMARY OF PRODUCT

Service Manual

U6U8 CN2 U27 CN3 CN4U7

OSC2

U3 U20 U11U10 U24 U13 CN13

CN8 OSC4 U26U17 U18 CN10 CN9 CN11

CN12

CN6

U13

OSC5U25 U14U15U1

ML-1710 (ML-1510) ML-1750

Processor Samsung Jupiter4 90MHz Samsung SPGPm 166MHz
PC Interface USB 1.1 USB 2.0

USB USB/IEEE1284 (Parallel)

Emulation SPL SPL, PCL6,

(Samsung Printer Language) IBM ProPrinter, EPSON

OS Compatibility Win 98/Me/2000/XP Win 9x/NT/4.0/Me/2000/XP

Various Linux OS, Various Linux OS,
Mac (Mac OS 8.6 ↑) Mac (Mac OS 8.6 ↑)

pcb FR-4, 2Layer FR-4, 4Layer

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SUMMARY OF PRODUCT

Samsung Electronics

Service Manual

4.4.1 Asic(SPGPm)

1) ARM946ES

- 32-bit RISC embedded processor core

- 16KB instruction cache and 16KB data cache

- No Tightly Coupled Memory

- Memory Protection Unit & CP15 control program

2) Dual bus architecture for bus traffic distribution

- AMBAHigh performance Bus (AHB)

- System Bus with SDRAM

3) IEEE1284 compliant parallel port interface

4) Printer Video Controller for LBP engines

5) Graphic Execution Unit for Banding support of Printer Languages

6) Printer Video Controller for LBP engines

- PVC : Printer Video Controller without RET Algorithm

- HPVC : Printer Video Controller with RET algorithm
(Line Memory & Lookup Table Memory : 512 x 8 , 4096 x 16)

7) Engine Controller

- Motor Control Unit

- Motor Speed Lookup Table Memory (128 x 16 x 2)

- Pulse Width Modulation Unit

- 4 Channels are supported

- ADC Interface Unit

- 3 ADC Channels are available

- ADC Core (ADC8MUX8) maximum clock frequency : 3 MHz

8) USB 2.0 Interface

9) Package

: 272 pins PBGA

10) Power

: 1.8V(Core), 3.3V(IO) power operation

11) Speed

: 166MHz core(ARM946ES) operation, 60MHz bus operation

4.4.2 Memory

1) Flash Memory

- It stores the System Program, downloads the System program through PC Interface, and compresses the

PCL font, then stores it.

- Capacity : 2M Byte

- Access Time : 70 nsec

2) DRAM

- It is used as Swath buffer, System working memory area, etc. when printing. It stores the font list, com-

pressed into flash memory, on DRAM and uses it as PCL font.

- Capacity : 8M Byte (Basic), upto 64M Byte (Factory Option)

- Type : SDRAM 100MHz/133MHz , 16bit

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SUMMARY OF PRODUCT

Service Manual

4.4.4 SPGPm Internal Block Diagram

AHB BUS

SFR BUS

INTERFACE

SYSTEM

BUS

INTERFACE

PARALLEL PORT

INTERFACE

UART(3CH)

SDRAM

CONTROLLER

(5CH)

HCT

ROTATOR/

SCALER/

HALFTONER

1024x8, 256x8x 4

gCODEC

GRAPHIC

EXECUTION

UNIT

MISC

CONTROLLER

ARM946E -S CORE

16KB ICACHE

16KB DCACHE

CLOCK & RESET

GENERATOR

SYSTEM BUS

ARBITER

MAC

USB2.0

EXTERNAL

DMA CONTROLLER

(4CH)

PVC

HPVC

512x8

4096x16

LSU I/F

PULSE WIDTH

MODULATOR

ENGINE

CONTROLLER

MOT OR

CONTROLLER

128x16 x2

ADC (3CH)

ADDR/

DATA
MUX

SFR Bus

System Bus

INTERRUPT
CTRL (5CH)

TIME CONTROL

UNIT

ENGINE

Comm. I/F

EPI

SYSMAC

SYSTEM PLL

(120MHz)

ARBITER

DECODER

ROM

CONTROLLER

IO

CONTROLLER

4-16

SUMMARY OF PRODUCT

Samsung Electronics

Service Manual

4.5 SMPS & HVPS

The SMPS supplies the DC power to the system.
It takes 110V/220V and outputs the +3.3V, +5V and +24V to supply the power to the main board and ADF
board.
The HVPS part creates the high voltage of THV/MHV/Supply/Dev and supplies it to the developer part for
making the best condition to display the image. The HVPS part takes the 24V and outputs the high voltage
for THV/MHV/BIAS, and the outputted high voltage is supplied to the toner, OPC cartridge, and transfer
roller.

MAIN PBA CON.

CN3

(FAN CON.)

CN1

(H/L CON.)

F101

250V L2A

EXIT SENSOR

CN4

(PANEL CON.)

MHV

OPC

DEV

SUPPLY

THV

COVER OPEN SWITCH

MANUAL SENSOR

FEED SENSOR

PAPER-EMPTY SENSOR

F1

110V : 125V/8A

220V : 250V T 5A H

F2

110V : 125V/3A

220V : 250V 2A H

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SUMMARY OF PRODUCT

Service Manual

4.5.1 HVPS(High Voltage Power Supply)

1) Transfer High Voltage (THV+)

- Function: It is a voltage to transfer a toner developed on OPC drum to a paper.

- Output voltage: Maximum +5.0KV ±5% (Duty changeable, unload)

- 1.0KV ±15%(When cleaning, 200MOhm)

- Error: If THV (+) doesn't output, a ghost status (same character is printed after one cycle (76mm)
of OPC) with a low density occurs due to a toner on OPC drum cannot normally transfer to a
paper.

2) Charge Voltage (MHV)

- Function: It is a voltage to charge entire surface of OPC with -900V ~ -1000V.

- Output voltage: -1.3KV ~ 1.8KV DC ±50V

- Error: If MHV doesn't output, a black paper is printed out because toner on developing roller
moves to OPC drum due to the surface of OPC is not charged.

3)Cleaning Voltage (THV-)

- Function: It removes a dirty on a surface by sending a minus toner in a transfer roller to an OPC

drum to recover toners.

- Output Voltage: There is no feedback control, so change range of output is big up to load.

- Error: Toner contamination occurs at a backside of a printed-paper.

4) Developing Voltage (DEV)

- Function: It is a voltage to develop a toner with using a difference of electronic potential on an

exposed part by LSU (Laser Scanning Unit).

* Generally, the electronic potential of exposed OPC is -180V and exposed developer is -350V

when printing, so toner with minus (-) is developed on an exposed part.

- Output voltage: -200V ~ 600V DC ±20V

- Error: 1. If DEV is GND, a density is going significantly down.

2. If DEV is floating due to instable contacting point of terminal, and etc., a density is signif­icantly going up.

5) Supply Voltage(SUP)

- Function: It is a voltage to supply toner to a developing roller.

- Output voltage: : -400V ~ 800V DC °æ 50V(Use ZENER, DEV gear)

- Error: 1. If SUP is GND, a density is dramatically going down.

2. If SUP is floating due to instable contacting point of terminal, and etc., a density is signif­icantly going down as much as it cannot be recognized with eyes.

4-18

SUMMARY OF PRODUCT

Samsung Electronics

Training Manual

4.5.2 SMPS(Switching Mode Power Supply)

It is the power source for the whole system. It is an independent module, so it is possible to use for com­mon use. It is mounted at the bottom of the set.
It is consisted of the SMPS part, which supplies the DC power for driving the system, and the AC heater
control part, which supplies the power to fuser. SMPS has three outputting channels (3.3V, +5V and +24V).
There are three kinds of power, 120V exclusive (America), 220V exclusive (Europe), and 220V for china
(nations with instable power supply).

1) AC Input

- Inputting rated voltage : AC 220V ~ 240V AC 120V / AC 220V

- Inputting voltage fluctuating range : AC 198V ~ 264V AC 90V ~ 135V / AC 198V ~ 264V

- Rated frequency : 50/60 Hz

- Frequency fluctuating range : 47 ~ 63 Hz

- Inputting voltage : Under 4.0Arms/2.0Arms
(The state when lamp is off or rated voltage is inputted/outputted)

2) Rated Power Output

3) Consumption Power

4) Length of Power Cord :

1830 ± 50mm

5) Power Switch :

Use

NO Item CH1 CH2 CH3 System

(+3.3V) (+5V) (+24V)

1 Stand-By 1.0 A 0.07A 0.4 A AVG : 55 Wh
2 PRINTING 1.0 A 0.14A 2.0 A AVG : 250 Wh
3 Sleep-Mode 0.8A 0.01A 0.4A A VG : 10 Wh

NO Item CH1 CH2 CH3 Remark

1 Channel name +3.3V +5V +24.0V
2 CONNECTOR PIN CON 3 CON3 CON 3

3.3V PIN: 3, 4 5V PIN : 8 24V PIN: 11, 12, 13
GND PIN: 5, 6 GND PIN: 7 GND : 9. 10

3 Rated outputting voltage 3.3V ± 5% +5V ± 5% +24V ±10%

(3.2 ~ 3.4V) (4.75 ~ 5.25V) (21.6 ~ 26.4V)
4 Maximum outputting voltage 1.0 A 0.14A 2.0 A
5 Peak loading voltage 1.5 A 0.14A 2.0 A 1ms
6 Ripple noise voltage 100mVp-p 100mVp-p 500mVp-p
7 Maximum output 3.3W 0.35W 48W
8 Peak output 4.95W 0.7W 60W 1ms
9 Uses Logic part LSU LD Main Motor

HVPS
Solenoid
Fan

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SUMMARY OF PRODUCT

Service Manual

6) Feature

- Insulating resistance : over 50MΩ (at DC500V)

- Insulating revisiting pressure : Must be no problem within 1min. (at 1500Vzc, 10mA)

- Leaking voltage : under 3.5mA

- Running voltage : under 40A peak (at 25°c, Cold start) Under 60Apeak (in other conditions)

- Rising Time : Within 2Sec

- Falling Time : Over 20ms

- Surge : Ring Wave 6KV-500A (Normal, Common)

7) Environment Condition

- Operating temperature range : 0°c ~ 40°c

- Maintaining temperature range : -25°c ~ 85°c

- Maintaining humid range : 30% ~ 90% RH

- Operating atmospheric pressure range : 1

8) EMI Requirement :

CISPR ,FCC, CE, MIC, C-Tick,

9) Safty Requrement

- IEC950 UL1950, CSA950, C-UL,NOM,TUV,Semko,Nemko,iK,CB, CCC(CCIB),GOST, EPA,

4.5.3 Fuser AC Power Control

Fuser (HEAT LAMP) gets heat from AC power. The AC power controls the switch with the Triac, a semicon­ductor switch. The 'On/Off control' is operated when the gate of the T riac is turned on/of f by Photo triac (insult­ing part).
In the other words, the AC control part is passive circuit, so it turns the heater on/off with taking signal from
engine control part.
When the 'HEATER ON' signal is turned on at engine, the LED of PC1 (Photo Triac) takes the voltage and
flashes. From the blinking light, the Triac part (light receiving part) takes the voltage, and the voltage is sup­plied to the gate of Triac and flows into the Triac. As a result, the AC current flows in the heat lamp, and heat
is occurred.
On the other hand, when the signal is off, the PC1 is off, the voltage is cut off at the gate of Triac, the Triac
becomes off, and then the heat lamp is turned off.

1) Triac (THY1) feature

- 12A,600V SWITCHING

2) Phototriac Coupler (PC3)

- Turn On If Current : 15mA~ 50mA(Design: 16mA)

- High Repetive Peak Off State Voltage : Min 600V

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SUMMARY OF PRODUCT

Samsung Electronics

Service Manual

4.6 Engine F/W

4.6.1 Feeding

If feeding from a cassette, the drive of the pickup roller is controlled by controlling the solenoid. The on/off
of the solenoid is controlled by controlling the general output port or the external output port. If feeding
from a manual feeder, decide to insert the paper according to the operation of the manual sensor, and by
driving the main motor, insert the paper in front of the feed sensor. While paper moves, occurrence of jam
is judged as below. (Refer to the [6.2 Paper Transfer rout])

4.6.1.1 Jam 0

• After picking up, paper cannot entered due to paper didn’t feed.

• After picking up, paper entered but it cannot reach to the feed sensor in certain time due to slip, etc.

• After picking up, if the feed sensor is not on, repack up. After repacking up, if the feed sensor is not on

after certain time, it is Jam 0.

- It is a status that the leading edge of the paper doesn’t pass the feed sensor.

• Even though the paper reaches to the feed sensor, the feed sensor doesn’t be on.

- It is a status that the leading edge of the paper already passes the feed sensor.

4.6.1.2 Jam 1

• After the leading edge of the paper passes the feed sensor, the tailing edge of the paper cannot pass the
feed sensor after certain time. (The feed sensor cannot be Off)

• After the leading edge of the paper passes the feed sensor, the paper cannot reach the exit sensor after
certain time. (The exit sensor cannot be On)

- The paper exists between the feed sensor and the exit sensor.

4.6.1.3 Jam 2

• After the tailing edge of the paper passes the feed sensor, the paper cannot pass the exit sensor after
certain time.

4.6.2 Drive

By gearing, the main motor drives the rollers such as feeding roller, developing roller, fuser roller, and dis­tributing roller. The step motor is controlled for the sections, acceleration section and fixed speed section.
In the initial stage of the motor run, appoint the acceleration section to prevent the isolation of the motor. It
is controlled by the A3977 motor driver IC. The step signal and the enable signal are sent to make the
phase for driving the motor in CPU.

4.6.3 Transfer

The charging voltage, developing voltage and the transfer voltage are controller by PWM (Pulse Width
Modulation). The each output voltage is changeable due to the PWM duty. The transfer voltage admitted
when the paper passes the transfer roller is decided by environment recognition. The resistance value of
the transfer roller is changed due to the surrounding environment or the environment of the set, and the
voltage value, which changes due to the environments, is changed through AD converter. The voltage
value for impressing to the transfer roller is decided by the changed value.

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SUMMARY OF PRODUCT

Service Manual

4.6.4 Fusing

The temperature change of the heat roller’s surface is changed to the resistance value through the thermis­tor. By converting the voltage value, which impressed to the resistance, to the digital value through the AD
converter, the temperature is decided. The AC power is controlled by comparing the target temperature to
the value from the thermistor. If the value from the thermistor is out of the controlling range while controlling
the fusing, the error stated in the table occurs. (For the domestic model, the Q-PID method has been
applied.)

4.6.4.1 Heat Lamp Method

4.6.4.2 Q-PID Method

Error Description DCU LED Displat

Open heat error When warming up, it has been lower 60 All LED are blinking.

than 68°C over 28 seconds

Lower heat error • Standby: 62 All LED are blinking

It has been lower than 80°C over 10 seconds

• Printing:

- 2 consecutive pages: it has been lower than
145°C over 4 seconds.

- 3 consecutive page; it has been 25°C lower
than the fixed fusing temperature over 4 seconds.

Over heat error It have been higher than 220°C over 3 seconds 68 All LED are blinking

Error Description DCU LED Displat

Open heat error When preheating, it has been lower than 68°C 60 All LED are blinking

over 15 seconds.

Lower heat error • After finishing the preheating stage, 62 All LED are blinking

it has not reached 100°C (preheating stop
temperature) during 15 seconds since the
temperature is over 68°C.

• Printing

1) When the main motor is on and after 0.92

second, it has not reached the 160°C
during 20 seconds.

2) From the 2 consecutive pages, it has been

20°C lower than the fusing temperature
over 4 seconds.

Over heat error • the error is not displayed immediately when 68 All LED are blinking

it has been over 220°C over 3 seconds.
The temperature after the 3 seconds is checked.
If it is over 240°C, it is error.

• If the temperature has been higher than 220°C
over 25 seconds, it is an error even through the
temperature doesn’t reach 240°C.

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SUMMARY OF PRODUCT

Samsung Electronics

Service Manual

4.6.4.3 What is the Q-PID Method?

The Q-PID is developed by Samsung, and it saves the preheating time in half in comparison with the existed
method. It saves not only the printing time for initial print but also it saves the printing speed for the reat­tempting print after for a while.

4.6.5 LSU

The LSU is consisted of the LD (Laser Diode) and the polygon motor control. When the printing signal occurs,
it turns the LD and drives the polygon motor. When the receiving light part detects the beam, Hsync occurs.
When the polygon motor speed becomes a normal, LReady occurs. If two conditions are satisfied, the sta­tus bit of the LSU controller register becomes 1 to be judged that the LSU is ready. If two conditions are not
satisfied, the error shown in below occurs.

Toner Toner

Air Layer
Holgen Lamp

Paper
Pressure Roller

Heat Pipe
Heating Wire
Paper

Pressure Roller

• After heating the air layer , transfer the heat to the
surface

• It takes long time to heat it until it reaches the
proper temperature.

• The high temperature is needed when it is stand­by status.

• The heat conductivity of the heat pipe is
100~150 times higher than cooper’s.

• It is possible to raise the temperature in an
instant

• It saves the dissipation of power in the standby
status due to high accumulation of heat.

Error Description DCU

Polygon motor error When the polygon motor’s speed doesn’t 95

become a normal

Hsync error The polygon motor’s speed is normal, 96

but the Hsync signal is not created.

5

5

5-1

Samsung Electronics

Disassembly and Reassembly

Service Manual

5. Disassembly and Reassembly

5.1 General Precautions on Disassembly

When you disassemble and reassemble compo­nents, you must use extreme caution. The close
proximity of cables to moving parts makes proper
routing a must.
If components are removed, any cables disturbed
by the procedure must be restored as close as
possible to their original positions. Before remov­ing any component from the machine, note the
cable routing that will be affected.

Whenever servicing the machine, you
must perform as follows:

1. Check to verify that documents are not stored
in memory.

2. Be sure to remove the toner cartridge before
you disassemble parts.

3. Unplug the power cord.

4. Use a flat and clean surface.

5. Replace only with authorized components.

6. Do not force plastic-material components.

7. Make sure all components are in their proper
position.

Releasing Plastic Latches

Many of the parts are held in place with plastic
latches. The latches break easily; release them
carefully.
To remove such parts, press the hook end of the
latch away from the part to which it is latched.

5-2

Disassembly and Reassembly

Samsung Electronics

Service Manual

1. Pull the Cassette out of the printer.

2. Remove the Front Cover in the direction of
arrow.

3. Remove four screws.

4. Unlatch the front ends of the Top Cover.

5. Remove the Top Cover in the direction of arrow.

6. Remove the Rear Cover from the Top Cover.

Cassette

5.2 Top Cover

Front Cover

Top Cover

Rear Cover

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Samsung Electronics

Disassembly and Reassembly

Service Manual

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

2. Unplug two connectors(Block) from the boards,
then remove four screws.

3. Remove two screws and take the Thermostat
out of the Fuser.

4. Remove two screws and take the Halogen
Lamp out of the Heat Roller.

5. Remove one screw and take the Idle Gear out.

6. Remove four screws and divide the Fuser into
two parts

7. Remove the Thermister from the Fuser Cover.

Idle Gear

5.3 Fuser

5.3.1 Fuser(Heat Lamp Type)

Thermister

Fuser Ass'y

Thermostat

Fuser Cover

Heat Roller

Halogen Lamp

5-4

Disassembly and Reassembly

Samsung Electronics

Service Manual

5.3.2 Fuser(Q-PID Type)

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

2. Unplug two connectors(Block) from the boards,
then remove four screws.

3. Remove two screws and take the Thermostat
out of the Fuser.

4. Remove two screws.

5. Remove one screw and take the Idle Gear out.

Fuser Ass’y

Thermostat

Idle Gear

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Samsung Electronics

Disassembly and Reassembly

Service Manual

6. Separate Heat Roller Ass'y after remove six
screws and after removing 6 screws as shown
in below, take out the heat roller assembly in
direction of the arrow while pulling the both side
of the unit-brush

Caution : • Be careful not to damage or contaminate the sur-

face of the roller when assembling/disassembling
the heat roller.

• Additional state: Be careful especially not to dam­age the covering of the fusing assembly.
(If the cover is damaged, it could cause an electric
leakage.)

7. Unplug Thermister Harness from the Fuser
cover.

8. Remove one screw and separate Thermister

from the inter connector Fuser Cover.

Thermister Harness

Fuser Cover

Heat Roller

Unit-Brush

Thermister

5-6

Disassembly and Reassembly

Samsung Electronics

Service Manual

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

2.Remove the Exit Gear, Bearing and Exit Roller

as shown below

Exit Gear

Bearing

Exit Roller

1

2

5.4 Exit Roller

5.5 LSU

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

2. Remove two screws and unplug one connector
from the Frame.

3. Remove the LED PBAAss’y as shown below.

4. Unplug two connector from the LSU

5. Unplug four screws and take the LSU out.

LED PBA Cover

LSU

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Disassembly and Reassembly

Service Manual

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

2. Unplug the connector from the SMPS and
remove the one screw. Then take out the Fan.

DC Fan

5.6 Fan

5.7 Driver Ass’y

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

2. Remove the six screws from the Drive Ass’y.

3. Unplug one connector from the Driver Ass’y

Drive Ass'y

5-8

Disassembly and Reassembly

Samsung Electronics

Service Manual

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

- Fuser Connector(see page 5-3)

2. Remove the fourteen screws securing from the
Engine Shield Ass’y and unplug the all connec­tors. Then take the Engine Shield Ass’y.

Engine Shield
Ass'y

5.8 Engine Shield Ass’y

5.9 Main PBA

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

- Engine Shield Ass’y(see page 5-8)

2. Unplug one connector and remove five screws
from the Main PBA. Then lift the Main PBA out,
as shown below.

Main PBA

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Disassembly and Reassembly

Service Manual

5.10 SMPS

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

- Engine Shield Ass’y(see page 5-8)

2. Unplug one connector and remove three screws
then take the Inlet Ass’y out.

3. Remove one screw and unplug one connector
from the Main PBA.

4. Remove three screws and take The SMPS out.

Inlet Bracket

SMPS

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Disassembly and Reassembly

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Service Manual

5.11 Transfer Roller

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

- LSU(see page 5-6)

2. Remove three screws and take the Transfer
Earth out.

3. Unplug the PTL Holder Connector, then remove
the PTL Holder and PTL Lens, as shown below.

4. Unlatch the Bush and remove it. Then lift the
Transfer Roller out, as shown below.

Transfer
Earth

PTL
Holder

PTL
Lens

Transfer
Roller

Bush

5-11

Samsung Electronics

Disassembly and Reassembly

Service Manual

5.12 Feed Roller

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

- Drive Ass’y(see page 5-7)

2. Remove two screws from the Guide Paper and
take it out.

3. Pull up the Feed Idle Bush and Feed Idle Shaft,
as shown below.

4. Remove three screws from the Feed Bracket
and take it out.

5. Remove the Idle Gear and Feed Gear2.

6. Remove the Feed Gear 1 Ass’y, as shown
below.

7. Remove the Feed Roller and Feed Roller 1, as
shown below.

Guide paper

Feed Idle
Shaft

Feed Gear2

Idle Gear

Feed Gear1
Ass'y

Bush

Feed Bracket

Feed Roller

Feed Roller1

5-12

Disassembly and Reassembly

Samsung Electronics

Service Manual

1. Before you remove the Fuser, you should
remove:

- Top Cover(see page 5-2)

- Drive Ass’y(see page 5-7)

- Engine Shield Ass’y(see page 5-8)

2. Remove three screws from the Feed Bracket
and take it out.

3. Remove the Pick up Gear Ass’y, as shown
below.

4. Remove the Pick up Ass’y, as shown below.

5. Remove two screw then remove The Manual
Solenoid and Pick Up Solenoid.

Pick up Gear
Ass'y

5.13 Pick Up Roller & Solenoid

(Pick up)
Solenoid

(Manual)
Solenoid

Feed Bracket

Bush

1

2

Pick up Ass'y

6

6

6-1

Samsung Electronics

ALIGNMENT & ADJUSTMENTS

Service

Manual

6. Alignment and Adjustments

This chapter describes the main functions for service, such as the product maintenance method,
the test output related to maintenance and repair, DCU using method, Jam removing method, and
so on. It includes the contents of manual.

6.1 How to use DCU

6.1.1 DCU Setup

You can examine the malfunction of the printer. To perform DCU, open the front discharge cover and leave
the connect the harness wire(10 pin/4 pin) to the CN3(ML-1750) or CN2(ML-1710/1510) of the Main control
board.

ML SERIES DIAGNOSTIC CONTROL UNIT

04

05

07

08

09

10

DEV 300

LSU READY

PAPER EMPTY

COVER OPEN

COER HEATING

DEV 350

LSU MT & LD

PAPER WIDTH

EXIT SENSOR

PRINTING TEMP

DEV 350

LSU MOTOR

NEW CRU

FEED SENSOR

READY HEAT

ON

OFF

STATUS

SELF

TEST

DIAGNOSTIC

DIAGNOSTIC CODE

00
01
02
03
04
05
06
07
08
09
10
11

12

13

14

61

00
01
02
03
04

20
30
40
50

69

60
62
68
64
70
71
72
73
95

MAIN MOTOR OPERATING SYSTEM
MAIN HIGH-VOLTAGE ON
TRNSFER HIGH-VOLTAGE (-)ON
THV(+) REFERANCE VOLTAGE
DEV/SUPPLY HIGH-VOLTAGE ON/PTL ON
LSU OPERATING SYSTEM
PICKUP CLUTCH ON
PEEMPTY/PWITH/NEW CRU TEST
FEED & EXIT SENSOR TEST
COVER OPEN SENSOR TEST
FUSER TEST
HOT BURN TEST

CLEAN MODE PRINT

THV(+)TRIGGER, ALL HV & FAN ON

THV(+) REFERENCE ON

ERROR STATUS CODE

STATUS CODE

WARM UP

READY (REGAL)
READY (LETTER)
READY (A4)
READY (EXECUTIVE)
READY (B5)

PRINT START
FEED SENSOR ON
FEED SENSOR OFF
PAPER OUT

SLEEP MODE

OPEN FUSER ERROR
LOW TEMPERATURE ERROR
OVER HEATING ERROR
COVER OPEN ERROR
NO PAPERR
PAPER JAM 0
PAPER JAM 1
PAPER JAM 2
LSU NOT READY

DIAGNOSTIC
MODE

DOWN

UP ENTER

SHIFT STOP

TO ENTER DIAGNOSTIC MODE, PUSH THREE BUTTONS SIMUL ANEOUSL
AND TURN THE PRINTER POWER ON.

6-2

ALIGNMENT & ADJUSTMENTS

Samsung Electronics

Service

Manual

6.1.2 Code

Connect DCU to the printer and turn the power on. It show 7 Segment FND on the panel and each code
tells the function of the printer.

1) Normal Code

While printing or warming up, it indicate the position of the paper

2) Error Code

When detecting the malfunction, the printing is stopped to indicate error code.

Code State Description

61 Warm up The printer is on, the cover is open or close.
00~05 Ready(kind of paper) The printer is ready, the paper is detected when the first paper is printed.

00: Legal ,01: Letter ,02: A4 ,03: EXEC ,04: B5 ,05: Folio, 06: A5/A6

20, 21, 22 Print Start The engine controller received the print order from the video controller.

20: 1st, 21: MP, 22: SCF
30 Feed Sensor On The paper is passing out of the Feed Sensor.
40 Feed Sensor off The paper has passed out of the Feed Sensor.
50 Paper Out The paper has passed out of Exit Sensor.
69 Sleep Mode The fuser power turned off to minimize the power consumption.

Code State Description

60, 62, 68 Fuser Error The error in the fuser occurred. There is a short circuit in the thermistor

and the thermostat while printing, Low Temperature Error occurs.

• 60: Open Fuser Error

• 62: Low Heat Error

• 68: Over Heat Error
64 Cover Open The Printer Cover is open.
65 CRU Error The Toner Cartridge not installed,
70 No Paper No paper in the paper cassette.
71 Paper Jam 0 The front part of paper is jammed between pickup unit and Feed sensor.
72 Paper Jam 1 The front part of paper is jammed between the Discharge sensor and

Feed sensor.

73 Paper Jam 2 The front part of paper is jammed just after passing through the discharge

sensor.
76 Out Bin Full The Out bin is filled with paper.
95 LSU Not Ready LSU Scanner Motor not ready or Hsync signal not output.

6-3

Samsung Electronics

ALIGNMENT & ADJUSTMENTS

Service

Manual

6.1.3 Self Diagnostic Mode

If Error code occurs due to malfunction of the printer, perform Self Diagnostic Mode to solve the problem.
The printer works only in the self-test mode to solve the malfunction problem.

To enter the self-test mode, turn the power on pressing the buttons of [Down], [Shift] and [Stop] at the same
time.
Release the button within 2 or 3 seconds if 78 shows in the DCU. If 00 shows in the DCU, press the button
[Up] or [Shift] to select the self+test , and press the button of [Enter] to operate. To stop, press the button of
[shift] and [Enter] together.

Code Description

00 Main Motor Operating System

Only the main motor is in operation.

01 Main High Voltage On(THV-)

-1400 voltage output by MHV terminal.

Caution : High voltage probe should be used.

02 Transfer High Voltage(-)On(THV-)

-1000 voltage output by MHV terminal.
Caution : High voltage probe should be used.

03 Transfer High Voltage (+)Reference on (THV +)

+800 voltage output by MHV terminal.

Caution : High voltage probe should be used.

04 DEV/supply High Voltage : DEV/Supply High Voltage Test.

The left one of the three LEDs in the self-test panel is on when DEV high voltage Supply
high voltage output by each HV terminal(-500V). Press the [Up] button to switch the volt­age. The middle and right one of the three LEDs are on and -650 voltage output by DEV
HV terminal.

Caution : High voltage probe should be used.

05 LSU Operating System

The scanning motor of LSU is in operation, the right LED of the three buttons on. Press
the [Up] button to Check LD. LD is functioning and the middle button is on. If the LD is
normal, all LEDs are on.

06 Pickup clutch on

The Solenoid in the printer is in operation. To stop the operation, Press the button [shift]
and [Enter] together.

6-4

ALIGNMENT & ADJUSTMENTS

Samsung Electronics

Service

Manual

Code Description

07 Paper Empty Sensor Test :

If activate the Actuator of the PEMPTY Sensor, the left and right of the three LEDs are
on.
Paper Empty Sensor ON/OFF 1st LED ON/OFF

08 Feed & Exit Sensor Test

Test the Feed sensor and Discharge sensor in the same way as '07'.
Feed Sensor ON/OFF 2nd LED ON/OFF
Exit Sensor ON/OFF 3rd LED ON/OFF

09 Cover Open Sensor Test

Test the Cover Open Sensor in th same way as code '07’
Cover Open Sensor ON/OFF 1st LED ON/OFF

10 Fuser Test

If the [Enter] button pressed, the right LED is on and temperature of the fuser is up to
READY Mode. If the [Up] button pressed, the middle LED is on and temperature of the
fuser is up to Printing Mode.
If you press the button once more, the left LED is on and temperature of the fuser is up
to overheat Mode.

11 Hot Burn Test

If the [enter] button pressed, the printer is continuously printing without detection.
Turn the power off to stop operation.

12 Cleaning Mode Print Mode

Print the paper to clean the OPC Drum in the Cartridge.

13 THV(+) TRIGGER. ALL HV :

All high voltage output by each HV terminal and LSU and the fan is in operation. In this
mode, electronic resistance of transfer roller and high voltage is detected.

14 PTL Test :

Indicates the function of the PTL, same method of the code ‘07’.

15 Fan Test :

Indicates the function of the Fan, same method of the code ‘07’.

16 Manual Pickup Test :

Indicates the function of th Manual Pickup, same method of the code ‘07’.

17 Manual Sensor Test :

Indicates the function of the Manual Sensor, same method of the code ‘07’.

6-5

Samsung Electronics

ALIGNMENT & ADJUSTMENTS

Service

Manual

6.1.4 Self Test Button

If the Self-Test button pressed, vertical lines are printed.
Turn the power on while pressing this button, '89' shows in the DCU and the printer is warming up. After

warming-up the printer is in READY Mode, and '88' shows in the DCU. In this mode, without any detection,
the printer begins printing(trial printing and data from the PC). It is convenient to use this mode when the
engine malfunction is detected in the control board.

No. Function Enter Up/ Dow n Stop Remar k

00

Motor

Motor Run Motor S top

01

MHV

Mhv On Mhv Off -1550V

02

THV(-)

Thv Negative On Thv Negative Off

03

THV(+)

Thv On Thv Off +1300V

04

DEV

Dev On

Supp ly DEV

De v O f f

0:-630V 0:-430V

05

LSU

LSU R un

On Off Ready

LSU Stop

06

Pic kUp

Pickup On Pickup Off

07

PEmpty

Pape r Empt y

08

Sen so r

Ex it Fee d

09

Cover

Cover Open

10

Fus er

Fuser On Fuser Off

11

Hot Bur n

Ho tB u rn O n

12

Clean Print

Cl e an Pr i nti n g

13

Thv

Refer ence

low adequate high

14

PTL

PTL On PTL Off

15

FAN

Fan O n Fan Off

16

Ma nu al

Pic kUp

Manual Pickup On Manual Pickup O ff

17

Ma nu al

Sen so r

Manual Sensor

6-6

ALIGNMENT & ADJUSTMENTS

Samsung Electronics

Service

Manual

6.2 Paper Path

PTL

P

I

C

K

/

R

PR

CR

DR

SR

TR FR

OPC

L S U

Fuser

Toner Cartridge

1

1

2

2

3

3

4

4

Paper Input (Cassette)

Paper Input (Manual Feeder)

Paper Out(Face Down)

Paper Out(Face Up)

5

5

6

6

7

7

Paper Empty Sensor

Paper Feeding Sensor

Paper Exit Sensor

Feed

Sensor

MP Sensor

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

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

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

1) After taking order, the printer feeds the printing paper from the cassette or manual feeder.

2) The fad paper passes the paper feeding sensor. (Jam 0 occurs if the sensor is not operated after certain

time passes)

3) The paper passed the paper feeding sensor moves to the paper exit sensor via printing process. (Jam 1

occurs if the sensor is not operated after certain time passes)

4) The paper passed the paper exit sensor moves out from the set. (Jam 2 occurs sometime after if the tail-

ing edge of the paper is not coming out from the set after the leading edge of paper passes the paper
exit sensor.)

<Jam0> <Jam1> <Jam2>

6-7

Samsung Electronics

ALIGNMENT & ADJUSTMENTS

Service

Manual

6.3 Clearing Paper Jams

Occasionally, paper can be jammed during a print job. Some of causes include:

• The tray is loaded improperly or overfilled.

• The tray has been pulled out during a print job.

• The front cover has been opened during a print job.

• Paper that does not meet paper specifications has been used.

• Paper that is outside of the supported size range has been used.

If a paper jam occurs, the On Line/Error LED on the control panel lights red. Find and remove the jammed
paper. If it is invisible, look inside the printer.
Do not use a pinset or a sharp metal tool when removing a jam.
The covering of a metal part can be removed which can cause an electric leakage.

6.3.1 In the Paper Exit Area (JAM2)

1) If the paper jams as it exits to the output tray and a
long portion of the paper is visible, pull the paper
straight out.

When you pull the jammed paper, if there is resis­tance and the paper does not move immediately, stop
pulling. Continue with the next step.

2) Open the rear output tray.

3) Loosen the paper if it is caught in the feed rollers.
Then pull the paper gently out.

Note: Please be careful when you open the rear cover.
The inside of the printer is still hot.

4) Close the rear output tray. Open and close the front
cover. Printing can be resumed.

6-8

ALIGNMENT & ADJUSTMENTS

Samsung Electronics

Service

Manual

6.3.2 In the Paper Feed Area

1) Open the front cover and remove the toner cartridge 2) Gently pull the paper toward you.

3) Check that there is no other paper in the printer.

4) Reinstall the toner cartridge, and then close the cover.
Printing can be resumed.

1) Slide out the tray to expose the jammed paper. 2) Remove any missfeed paper by pulling it out by the visi­ble edge from the tray. Make sure that all of the paper is
properly aligned in the tray.

3) Slide the tray back into the printer. Open and close the
front cover. Printing can be resumed.

6.3.2 In the Paper Feed Area (JAM0)

6.3.3 Around the Toner Cartridge (JAM1)

6-9

Samsung Electronics

ALIGNMENT & ADJUSTMENTS

Service

Manual

6.3.4 Tips for Avoiding Paper Jams

By selecting the correct paper types, most paper jams can be avoided. If a paper jam occurs, follow the
steps outlined in

• Ensure that the adjustable guides are positioned correctly.

• Do not overload the tray. Ensure that the paper is below the paper capacity mark on the right inside of
the tray.

• Do not remove the paper from the tray while printing.

• Flex, fan and straighten the paper before loading.

• Do not use creased, damp or highly curled paper.

• Do not mix paper types in the input tray.

• Use only recommended print media.

• Ensure that the recommended print side is facing down when loading paper into the input tray.

6-10

ALIGNMENT & ADJUSTMENTS

Samsung Electronics

Service

Manual

6.4 Sample Pattern

This product has the several sample patterns for maintenance. With the sample patterns, check the exis­tence of the abnormality. The patterns help to regularly maintain the product.

6.4.1 Printing a Demo Page

Print a demo page or a configuration sheet to make sure that the printer is operating correctly.

1) Hold down the Cancel button for about 2 seconds to print a demo page.
Hold down the Cancel button for about 6 seconds to print a configuration sheet.

2) The Demo page or the configuration sheet shows the printer’s current configuration.

<Demo Page : ML-1710> <Demo Page : ML-1750>

6-11

Samsung Electronics

ALIGNMENT & ADJUSTMENTS

Service

Manual

6.4.2 Printing a cleaning sheet

If you are experiencing blurred, faded or smeared printouts. Printing a cleaning sheet cleans the drum
inside the toner cartridge. This process will produce a page with toner debris, which should be discarded.

1) Ensure that the printer is turned on and in the Ready mode with paper loaded in the tray.

2) Press and hold down the Cancel button on the control panel for about 10 seconds.

3) Your printer automatically picks up a sheet of paper from the tray and prints out a cleaning sheet with
dust or toner particles on it.

Note:The cartridge cleaning process takes some time. To stop printing, turn the power off.

<System Data List : PCL Model Only>

6-12

ALIGNMENT & ADJUSTMENTS

Samsung Electronics

Service

Manual

COMPONENT REPLACEMENT CYCLE

Pick-up Roller 60,000 Pages

Paepr Feeding Roller(Friction Pad) 60,000 Pages

Transfer Roller 60,000 Pages

Fuser 60,000 Pages

Toner Cartridge 3,000 Pages

6.5 Consumables and Replacement Parts

The cycle period outlined below is a general guideline for maintenance.
The example list is for an average usage of 50 transmitted and received documents per day.
Environmental conditions and actual use will vary these factors.
The cycle period given below is for reference only.

6.6 The LED Status Display by Each Error

ERROR LED Status DCU CODE

Open Fuser Error The [Error] LED (red) and the [Toner Save] LED are simultaneously 60

flashing every one-second.

Over Heat Error The [Error] LED (orange) and the [Toner Save] LED are 68

simultaneously flashing every one-second.

Low Heat Error The [Error] LED (red) and the [Toner Save] LED are simultaneously 62

flashing every 4 seconds.
LSU not Ready Error The [Error] LED (green) and the [Toner Save] LED are 95
(Pmotor Error) simultaneously flashing every one-second.
LSU Not Ready Error The printing is stop in the fad status, and the [Error] LED (green) and 96
(HSYNC Error) the [Toner Save] LED are simultaneously flashing every 4 seconds.

6-13

Samsung Electronics

ALIGNMENT & ADJUSTMENTS

Service

Manual

6.7 Periodic Defective Image

If the delinquent image regularly occurs in the printed-paper, it is due to delinquent or damaged roller.
Refer to the table in below and check the condition of the roller.

No Roller Defective image Typical defect

1 OPC Drum 75.5mm white spot on black image or black spot
2 Charge Roller 37.7mm black spot
3 Supply Roller 37.0mm light or dark horizontal image band
4 Developing Roller 35.3mm horizontal image band
5 Transfer Roller 45.3mm image ghost
6 Heat Roller 64.1mm Black spot and image ghost
7 Pressure Roller 75.5mm black spot on the backside

PTL

L S U

Fuser

Toner Cartridge

1

2

3

7

6

5

4

MP Sensor

1
2
3
4

OPC Drum

Charge Roller

Supply Roller

Developing Roller

5
6
7

Tramsfer Roller

Heat Roller

Pressure Roller

PTL

P

I

C

K

/

R

PR

CR

DR

SR

TR FR

OPC

L S U

Fuser

Toner Cartridge

MP Sensor

<Rollers Layout>

6-14

ALIGNMENT & ADJUSTMENTS

Samsung Electronics

Service

Manual

7

7

7-1

Samsung Electronics

TROUBLESHOOTING

Service Manual

7. Troubleshooting

7.1 Bad image

7.1.1 Vertical Black Line and Band

• Description

1. Straight thin black vertical line occurs in the printing.

2. Dark black vertical band occur in the printing.

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. Damaged develop roller in the Developer.
Deformed Doctor-blade or cleaning­blade.

2. Scratched surface of the discharge roller
in the developer.

3. Partly depression or deformation on the
surface of the transfer roller.

1. If causes 1 and 2 occur in the developer
cartridge, replace the developer and try to
print out.

2. Replace the transfer roller if occurred as
No. 3.

7.1.2 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. Foreign matter stuck onto the window of
internal lenses of LSU mirror.

2. Foreign matter or toner particles between
the developer roller and blade.

(In case the life of the developer has
been expired, white lines or light image
occur in front of the image.)

3. It may occur when Burr and foreign sub­stances are on the window of the devel­oper frame.

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

1. Foreign matter stuck onto the window :
Clean the LSU window with recommend­ed cleaner(IPA) Clean the window with a
clean cotton swab.

2. Foreign matter in the LSU : Open the
cover of LSU and clean with a cotton
swab on the surface of the reflex mirror.

3. No 3. : Remove the foreign matter and
burr of the exposure window.
(Developer cartridge)

4. No. 4. : Open the front cover and check
ribs that corresponds to the position of
the voids. Remove if found.

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

7-2

TROUBLESHOOTING

Samsung Electronics

Service Manual

7.1.3 Horizontal Black Band

• Description

1. Dark or blurry horizontal stripes occur in the printing periodically.
(They may not occur periodically.)

Digital Printer
Digital Printer
Digital Printer
Digital Printer
Digital Printer

Check and Cause Solution

1. Bad contacts of the voltage terminals to
developer.

2. The rollers of developer may be stained.
Charge roller = 37.7mm
Supply roller = 37mm
Develop roller = 35.3mm
Transfer roller = 45.3mm

1. Clean each voltage terminal of the Charge,
Supply, Develop and Transfer roller.

(remove the toner particles and paper par­ticles)

2. Clean the right Gear that has relatively
small gap of the teeth in the OPC.

3. If the malfunction persists, replace the
developer.

7.1.4 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. Run OPC cleaning Mode Print and run the
Self-test 2 or 3 times.

2. In case of 75.5 mm interval unremovable in
1, cleanly remove foreign substances stuck
on the OPC location equivalent to black
spots and white spots with a dry duster.

3. The transfer roller guarantees 60.000
sheets printing. If the roller's life is expired,
replace it.

4. In case of 37.7 mm interval unremovable in
1, take measures as to replace the develop­er cartridge and try to print out.

5. Clean the inside of the set against the paper
particles and foreign matter in order not to
cause the trouble.

7-3

Samsung Electronics

TROUBLESHOOTING

Service Manual

7.1.5 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. Develop roller is stained when the toner
of developer cartridge is almost con­sumed.

2. Ambient temperature is below than 10°C.

3. Bad contact caused by the toner stains
between the high voltage terminal in the
HVPS and the one in the set.

4. Abnormal output from the HVPS.

1. Check if the Toner Save mode is off.

2. R

eplace the developer cartridge and try to

print out.

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

4. Clean up the contaminated area by the
toner.

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

7.1.6 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.
( Perform DCU diagnostic code 01)

2. Charge voltage is not turned on due to

the bad contacts between power supply
in the side of the Developer and charge
terminal of HVPS.

1. Clean the high voltage charge terminal.

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

3. Replace the HVPS if not solved by the
above direction 1 and 2.

7-4

TROUBLESHOOTING

Samsung Electronics

Service Manual

7.1.7 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 holder is damaged.

2. The toner level is not even on the devel­oper roller due to the bad blade.

1. Replace both the left and right Spring
Holder.

2. Occur in the developer cartridge, replace
the developer and try to print out.

7.1.8 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.

Does character exist less than 2%
per a page, and hasn’t it been used
long time?

2.

Does recycle paper be used?

3.

Has the life span of the developer
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
3,000 sheets (around 5,000 sheets)
with 2% image, a background can be
occurred.

2.

The B/S is not guaranteed if using
recycle paper.

3.

Replace the developer when the life
span of it has been ended.

4.

Clean the bushing part of the transfer
roller.

5. If the problem is still not solved,

replace the developer.

7-5

Samsung Electronics

TROUBLESHOOTING

Service Manual

7.1.9 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

75.5mm

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 Developer.

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 developer is expired.

4. Transfer roller lifetime(60.000 sheets) has
expired.

5. Abnormal low temperature(below 10°C).

1. Clean the terminals when contaminated by
toner particles.

2. Occur in the developer cartridge, replace
the developer and try to print out.

3. Replace the engine board if not solved by
the above directions 1-2.

4. If not solved by the direction 3, check the
transfer roller lifetime and replace it.

5. Wait about 1 hour after power on before
using printer.

7.1.10 Ghost (2)

• Description

Ghost occurs at 75.5 mm intervals of the OPC drum in the whole printing.
(When printing on card stock or transparencies using manual feeder)

Digital Printer

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Digital Printer

Digital Printer

75.5mm

Check and Cause Solution

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

Select 'Thick Mode' on paper type menu from
the software application and after using return­ing to the original mode is recommended.

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7.1.11 Ghost (3)

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

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37mm

Check and Cause Solution

1. The life of the developer may be expired.

2. The abnormal voltage and bad contact of
the terminal of the supply roller

1. Occur in the developer cartridge, replace
the developer and try to print out.

2. Check the approved voltage of the supply
roller and contact of the terminal and adjust
if necessary.

7.1.12 Ghost (4)

• Description Ghost occurs at 47 mm intervals.

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

Digital Printer

47mm

Check and Cause Solution

The temperature of the fuser is maintained
high.

1. Disassemble the fuser and remove the
contaminated toner particles on the roller
and clean the foreign matter between
Thermistor and Heat roller.
( Caution : can be deformed)

7.1.13 Satins on the Face of Page

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

Digital Printer
Digital Printer
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Check and Cause Solution

1. Toner leakage due to improperly sealed
developer.

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

1. Replace the developer cartridge.

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

remove contamination.

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7.1.14 Satins on Back of Page

• Description The back of the page is stained at 47 mm intervals.

Digital
Digital Pri
Digital Printer
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Digital Printer

Check and Cause Solution

1. Transfer roller is contaminated.

2. Pressure roller is contaminated.

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

2. Replace the transfer roller if contaminated
severely .

3. Disassemble the fuser and clean the
H/R(Heat Roller) and P/R(Pressure roller).
And check the area between H/R and
Thermistor. If contaminated, clean the area
not to be deformed.

7.1.15 Blank Page Print out (1)

• Description Blank page is printed.

Digital Printer
Digital Printer
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Check and Cause Solution

Bad ground contacts in OPC and/or devel­oper.

Remove contamination of the terminals of the
developer and the unit.

7.1.16 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. Bad ground contacts in OPC and/or
developer.

2. Abnormal solenoid.

1. Remove contamination of the terminals of
the developer.

2. Perform the engine self test using DCU to

check

if the Solenoid is normal.(refer to code 06)

3. If not solved by the above directions 1-2,
Replace the engine board.

4. Turn the power off, delete the data of PC
and try printing again.

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7.2.1 Wrong Print Position

• Description Printing begins at wrong position on the paper.

Check and Cause Solution

Wrong sense time caused by defective feed sensor
actuator.

Replace the defective actuator

Check and Cause Solution

1. Check the Solenoid by using DCU diagnostic mode

06.

2. Check if the pad is loose due to bad sealing of the
side-pad.

3. Check the surface of the roller-pickup for foreign mat­ter.

4. If the paper feeds into the printer rand Jam 0 occurs,
perform DCU to check feed-sensor of the engine
board.

1. Replace the solenoid.

2. Replace the side-pad Assembly Lor R, if necessary.

3. Clean with soft cloth dampened with IPA(Isopropyl
Alcohol) or water.

4. Replace the SMPS-HVPS and/or Sensor.

7.2.2 JAM 0

• Description

1. Paper is not exited from the cassette.

2. Jam-0 occurs if 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

7.2 bad discharge

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Check and Cause Solution

1. If the recording paper is jammed in front of or inside
the fuser. (Perform DCU diagnostic code 08)

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

1. Replace the SMPS.

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

7.2.3 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.

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

• After the paper is completely discharged, actuator

Exit should return to the original position to shut the
photo-sensor. Sometimes it takes longer hour than it
should and does not return.

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

• This occurs when a Guide claw is broken away or

transformed.

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

away or transformed.

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

3. Paper is accordion in the fuser.

1. Check if the exit sensor actuator is defective.

• Check if the actuator exit is unformed (Check if the
lever part is unformed in shape).

• Check whether burrs occur in the assembly part of
the actuator exit or not and if the actuator is
smoothly operated.

• Check if foreign matters and wire get caught in the
actuator exit's operation.

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.

3. Remove the jammed paper after disassembling the

fuser : Clean the surface of the pressure roller with
dry gauze.

• Remove the toner particles stained on the rib.

• Check the assemblage and performance of the exit.

7.2.4 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.

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

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7.2.5 Multi-Feeding

• Description Multiple sheets of paper are fed at once.

Check and Cause Solution

1. Solenoid malfunction(the solenoid does not work
properly): Perform DCU Diagnostic Code 06.

2. Pad-Friction is contaminated with foreign matter.(oil...)

3. The face of paper is blended.

1. Replace the solenoid if necessary.

2. Clean the pad friction with soft clothe dampened
with IPA(Isopropyl Alcohol).

3. Use the smooth paper.

7.2.6 Paper rolled in the Fuser

• Description If contaminated at intervals of 57mm on the back of a paper.

Check and Cause Solution

1.

Contamination of the pressure roller or heat
roller (Background, Hot off set).

2.

Check the claw of the fuser whether it is unfit­ted.

1.

After disassembling the fuser, clean contami­nation between the heat roller and the ther­mostor and remove the contamination of the
pressure roller.

2.

If there is heavy background, repair it by the
background troubleshooting method.

3. The surface of the heat roller with IPA or

water

4. Check the warp or separation of the sprint

claw and the holder plate claw, and then man­age it.

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7.2.7 Paper rolled in the Toner Cartridge (OPC Drum)

• Description Paper is rolled up in the OPC.

Check and Cause Solution

1. Paper is too much thin.

2. The face of paper is curled.

1. Recommend to use normal paper.

2. How to remove the rolled in the OPC Drum.

• Remove the paper while turning the OPC
Drum against the ongoing direction.

• C;eam fomger[romts on the OPC Drum
spft;u with IPA(Isopropyl Alcohol) or tissue.

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7.3 Malfunction

7.3.1 All LEDs blinking (Fuser Error)

• Description

1. All the lamps on the operator panel blink.

2. Gear of the fuser does not work and breaks away melt away.
When printing, motor breaks away from its place due to defective fuser gear.

Check and Cause Solution

1. Check if the thermostat, AC wire and Heat Lamp is
open.

2. Check if the thermistor sensor is in place.

3. Check if the heat lamp works properly.

4. Check if the overheat circuit works properly.

5. The fuser gear is defective due to melting away.

1. If the thermostat is open replace the fuser and
check following items.

2. If the thermistor sensor device is located deep in the
sponge, replace the fuser.

3. Check if the circuit of overheat mode works properly.

4. Run DCU mode : Perform DCU diagnostic code 10.

5. Replace Fuser.

7.3.2 All LEDs blinking (Scan Error)

• Description

1. All lamps on the operator panel blink.

Check and Cause Solution

DCU Mode : Perform DCU diagnostic code 05. If the DCU
error code 95 is displayed, replace LSU.

Replace LSU.

If you cannot solve the problem after you replace LSU,
replace the main board.

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7.3.3 Not function of the gear of the fuser due to melting away

• Description

The motor breaks away from its place due to gear melting away.

Check and Cause Solution

DCU Mode : Check if the Error States '60' '62' '68' occur.

Check the operation of Fuser Erasing Lamp
On/Off with the Error Code Check -10-.

1. Replace the Fuser.

2. Replace the Main Control board.

7.3.4 Paper Empty

• Description

The paper lamp on the operator panel is on even when paper is loaded in the cassette.

Check and Cause Solution

1. Bending or deformation of the actuator of the paper sen­sor.

2. The function of the engine board is defective Perform
DCU mode : Perform DCU diagnostic code 8.

1. Replace the defective actuator.

2. Replace the engine board.

7.3.5 Paper Empty without indication

• Description

The paper lamp on the operator panel does not come on when the paper cassette is empty.

Check and Cause Solution

1. Bending or deformation of the actuator of the paper sen­sor.

2. The function of the engine board is defective Perform.
DCU mode : Perform DCU diagnostic code 8.

1. Replace the defective actuator.

2. Replace the engine board.

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7.3.6 Cover Open

• Description

The ERROR lamp is on even when the print cover is closed.

Check and Cause Solution

1. The Hook Lever in the top cover may be defective.

2. Check the connector (Engine B’d↔HVPS) and circuit of
the cover switch department in the Main Control board.
Perform DCU mode : If Error state '64' occurs, Check the
related codes of the Cover Open Error.

1. Replace the hook lever, if defective.

2. Check the insertion of the Cover Open S/W
Connect.

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

7.3.7 No lamp on when the cover is open

• Description

The ERROR lamp does not come on even when the printer cover is open

Check and Cause Solution

1. Check the connector(CN8) and circuit of the cover switch
department in the Main Control board. Perform DCU
mode : If Error state '64' occurs, Check the related codes
of the Cover Open Error

1. Check the insertion of the Cover Open S/W
Connect.

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

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7.3.8 Defective motor operation

• Description

Main motor is not driving when printing, and paper does not feed into the printer, resulting 'Jam 0'.

Check and Cause Solution

1. Motor harness or sub PCB may be defective.

2. Perform DCU diagnostic code 00 and Check the motor
operation.

1. Check the motor harness, replace it, if defective.

2. Replace the SMPS, if necessary.

7.3.9 No Power

• Description

When system power is turned on, all lamps on the operator panel do not come on.

Check and Cause Solution

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

2. Check the inferiority of LED-Panel on the front-cover if
the LED of Panel does not appear after normal warming­up.

1. Replace the power supply cord or SMPS.

2. Replace the control board.

3. Replace the LED-panel.

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7.3.10 Vertical Line Getting Curved

• Description

When printing, vertical line gets curved.

Check and Cause Solution

1. If the supply of +24v is unstable in the Main Control board
linking with LSU, check drive by DCU Mode : LSU Check

-05- LSU Motor on.

1. Replace LSU.

2. Replace the Main Control board.

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7.4 Toner Cartridge Service

It is not guaranteed for the default caused by using other toner cartridge other than the cartridge supplied
by the Samsung Electronic or caused by non-licensed refill production.

7.4.1 Precautions on Safe-keeping of Toner Cartridge

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

7.4.2 Service for the Life of Toner Cartridge

If the printed image is light due to the life of the toner, 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 thoroughly.

7.4.3 Redistributing Toner

When toner is low, faded or light areas may appear on a printed page. You may be able to temporarily
improve the print quality by redistributing the toner. The following procedures may allow you to finish the
current print job before replacing the toner cartridge.

1) Grasp the front cover and pull it toward you to
open.

2) Remove the toner cartridge from the printer

3) Gently shake the toner cartridge from side to side
five or six times to redistribute the toner.

4) Reinsert the toner cartridge into the printer.
Ensure that the toner cartridge snaps into place.

5) Close the front cover. Make sure that the cover is
securely closed.

1.7

Note :

Avoid reaching too far into the printer. The fusing
area may be hot.
To prevent damage to the toner cartridge, do not

expose it to light for more than a few minutes.

Note :

If the toner gets on your clothing, wipe it off with a dry
cloth and wash clothing in cold water. Hot water sets
toner into fabric.

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7.4.4 Signs and Measures at Poor toner cartridge

Fault Signs Cause & Check Solution

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

T oner
Contamination

• The printed image
is light or unclean
and untidy.

• Some part of the
image is not print­ed.

• Periodically a noise
as "tick tick" occurs.

• Toner is fallen on
the papers periodi­cally .

• Contaminated with
toner on prints part­ly or over the whole
surface.

1. If the image is light or unclean
and untidy printed image ­Shake the developer and
then recheck.

(1)NG : Check the weight of

the developer

(2)OK : Lack of toner, so the

life is nearly closed.

2. Some part of image is not
printed - Shake the develop­er and then recheck.

(1)NG : Check the weight of

the developer and
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 as "tick
tick" occurs - Measure the
cycle and the weight of the
developer.

4. White vertical stripes on the
whole screen or partly :
Check the weight of the
developer.

1. Toner is fallen on the paper
periodically .

(1)Check the cycle of the

falling of the toner.

(2)Check the appearance of

both ends of the developer
OPC drum.

2.The center of the printed mat-

ter is contaminated with toner.

(1)Check whether foreign sub-

stances or toner are stuck
to the terminal (contact
point) of the developer.

(2)Check whether the state of

the terminal assembly is
normal.

1. All of 1, 2, 3 above­If it become better by shaking,
replace with a new developer
after 35.3-100 sheets in the
closing state of the life span.

2. In case of 2­If it becomes better after clean­ing the LSU window, then the
developer is normal.
(Because of foreign substance
on the LSU window, the image
has not been printed partly.)

3. In case of 3­If the cycle of noise is about 2
seconds, the toner inside the
developer has been nearly
exhausted.( Purchase and
replace with a new developer
after using about 200 sheets at
the point of occurrence)

4. In case of 3­This is a phenomenon caused
by lack of toner, so replace with
a new developer.

1. If both ends of the OPC drum
are contaminated with toner:

Check the life of the developer.

2. Check whether it could be recy­cled.

3. If it cannot be recycled:

Replace the developer.

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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 developer.

• Unclean and rough
printouts.

• Bad background in
the image.

1. If light or dark periodical black
dots occur, this is because the
developer rollers are contami­nated with foreign substance
or paper particles.

(1)37.7mm interval : Charged

roller

(2)75.5mm interval : OPC cycle

2. If white spots occur in a black

image at intervals of 75.5mm,
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 devel­oper.

(1)Check the damage to label

and whether different materi­als are used.

(2)Check the appearance of

parts of the developer, such
as frame, hopper.

2. Unclean and rough printouts.

(1)Check whether foreign sub-

stance or toner are stuck to
the terminal (contact point) of
the developer.

(2)Check whether the state of

the terminal assembly is nor­mal.

1. In case of 1 above ­Run OPC Cleaning Mode Print
4-5 times repeatedly to remove.
Especially check foreign sub­stance on the OPC surface, then
remove them with a clean gauze
moistened with IPA(Isopropyl
Alcohol) not to damage OPC if
necessary .

Never use usual alcohol.

2. In case of 2
If they are not disappeared by
running OPC Cleaning Mode
Print 4-5 times.

:

at intervals of 37.7mm

- Replace

the developer.

: at intervals of 75.5mm - Remove

foreign substance.

: Broken image - Replace the

developer according to careless­ness.

3. In case of 3 - Exchange the
transfer roller because the life of
the transfer roller in use has been
expired. (Check the transfer volt­age and readjust if different.)

1. In case of 1 -

(1)If there is an evidence of disas-

sembling the developer.

(2)If materials other than normal

parts of the developer are
added or substituted.

2. In case of 2 - If there are any
abnormals in connection with the
situation of 1.

(1)It occurs when the developer

is recycled over 2 times.

(2)If toner nearly being expired

are collected to use, it is
judged as the recycled devel­oper.

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7.5 Bad Environment of The Software

7.5.1 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 : Turn the power on while pressing
the test printing button for 2 or 3 seconds before printing
works.

2. Check if the PC and the printer is properly connected
and the toner cartridge installed.

3. Printing is nor working in the Windows.

4. Check if the printer cable is directly connected to periph­eral devices

1.Check the power of the printer and perform the Self­Test. If the test printing works, that means no prob­lems in the printer itself. If the test printing does not
work, that means bad functioning of the printer(not
because of software). Perform DCU to check the
Error Status.

2. Replace the printer cable. If the problems not solved

even after the cable replaced, check the amount of
the remaining tone.
(refer to Toner Cartridge Service 7.4)

3. Check if the connection between PC and printer port

is proper. If you use windows, check if the printer dri ­ver in the controller is set up. If the printer driver is
properly set up, check in which program the printing
is not working. The best way to find out is to open the
memo pad to check the function of printing. If it is not
working in a certain program, adjust the setup the
program requires. Sometimes, the printout is normal
within the Windows basic programs, but it's not work­ing in a particular program. In such case, install the
new driver again. If not working in the Windows basic
program, Check the setup of the port of CMOS is on
ECP. And check the address of IRQ 7 and 378

4. If the scanner needs to be connected to the printer,

first the remove the scanner from the PC to see if the
printer is properly working alone.

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7.5.2 The printer is not working (2)

• Description

After receiving the printing order, no response at all or the low speed of printing
occurs due to wrong setup of the environment rather than malfunction of the printer itself.

Check and Cause Solution

1. Secure more space of the hard disk.

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 hard disk space problem rather than
the RAM problem. In this case, provide more space
for the hard disk. Secure more space using the disk
utilities program.

2. The connection of the cable and printer port is not
proper. Check if the connection is properly done and
if the parallel port in CMOS is rightly set up.

3. As a printer port, Select ECP or SPP among
SPP(Normal), ECP, and EPP modes(increase print­ing speed) SPP normal mode support 8-bit data
transfer, while ECPMode transfer the 12-bit data.

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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7.5.3 Abnormal Printing

• Description

The printing is not working properly even when the cable has no problem.
(even after the cable is replaced)
If the printer won't work at all or the strange fonts are repeated, the printer driver may be defec­tive or wrong setup in the CMOS Setup.

Check and Cause Solution

1. Set up the parallel port in the CMOS SETUP.

2. Printer Driver Error.

3. Error message from insufficient memory.
(The printing job sometimes stops or due to insufficient
virtual memory, but it actually comes from the insuffi­cient space of the hard disk.)

1. Select SPP(Normal) or ECP LPT Port the among
ECP, EPP or SPP in the CMOS Setup.

2. Check the printer in My Computer.(to see if the
printer driver is compatible to the present driver or
delete

the old driver, if defective and reinstall the new

driver)

3. Delete the unnecessary files to secure enough
space of the hard disk and start printing job again.

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7.5.4 SPOOL Error

• Description

To spool which stands for "simultaneous peripheral operations online" a computer document or
task list (or "job") is to read it in and store it, usually on a hard disk or larger storage medium so
that it can be printed or otherwise processed at a more convenient time (for example, when a
printer is finished printing its current document).

Check and Cause Solution

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

2. If the previous printing error not solved.

3. When expected to collide with other program.

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

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

6. Memory is less than suggested one.

1. Delete the unnecessary files to provide more space
to start printing job.

2. If there are some files with the extension name of
****.jnl, Delete them and Reboot the Windows to
restart printing job.

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 program
to do the printing job.

6. Add up enough 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 the delete menu.

If you intend to delete the current document being printed, the data being transferred to the printer will be put
out and then the document is removed. Before choosing the document, the menu is still inactive.

Or put the document out of the list and repeat the routine as in the above or finish the spool manager.

8

8

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EXPLODED VIEW & PA RTS LIST

Service Manual

8. Exploded Views and Parts List

5-1. Main Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page(5-2)

5-2. Frame Unit Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . page(5-4)

5-3. Drive Unit Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . page(5-7)

5-4. Cassette Unit Assembly . . . . . . . . . . . . . . . . . . . . . . . . . page(5-8)

5-5. Fuser Unit Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . page(5-10)

8-2

EXPLODED VIEW & PA RTS LIST

Samsung Electronics

Service Manual

8.1 Main Assembly

0

9

6

7

8

2-2

2-3

2-4

2-5

2-6

2-6

15

2-1

2-7

2-8

1

2

10

4

11-1

11

11-2

11-3

11-4

11-5

11-3

12

17

13

14

5

20

19

3

18

16-1

16-3

16-2

16

8-3

Samsung Electronics

EXPLODED VIEW & PA RTS LIST

Service Manual

No. Description SEC.Code Q’ty SA Remark

0 ML-1710 / ML-1750
1 ELA UNIT-FRAME LOWER, 110V JC96-02732A 1 O 110V
2 MEA UNIT-COVER TOP JC97-01748A 1 O ML-1710/XAA

MEA UNIT-COVER TOP JC97-01749A 1 O ML-1750/XAA
MEA UNIT-COVER TOP JC97-01748F 1 O ML-1710/XAX

MEA UNIT-COVER TOP JC97-01749N 1 O ML-1750/XAX
2-1 LENS LED-M-LED JC67-00026A 1 O
2-2 COVER-M-TOP JC63-00102A 1 O ML-1710/XAA

COVER-TOP JC63-00102F 1 O ML-1750/XAA

COVER-TOP JC63-00102T 1 O ML-1710/XAX

COVER-TOP JC63-00102U 1 O ML-1750/XAX
2-3 COVER-M-REAR JC63-00101A 1 O
2-4 PMO-ST ACKER_RX JC72-00973A 1 O
2-5 PMO-BUSHING_F/DOWN * 1 X
2-6 PMO-SUB STACKER JC72-01001A 2 O
2-7 SPRING-CS 6107-001 169 1 O
2-8 KEY-M-ON LINE JC64-00039A 1 O

3 PLATE-P-CHANNEL JC61-00606A 1 O
4 CBF HARNESS-MOTOR JC39-00241A 1 O
5 SMPS- V1(XAA) JC44-00046A 1 O 110V
6 UNIT-HUMMINGBIRD LSU JC59-00018A 1 O
7 PBA MAIN-PANEL JC92-01439A 1 O
8 COVER PCB-M-PCB JC63-00104A 1 O
9 CBF HARNESS-LSU JC39-00242A 1 O
10 ELAUNIT-RX DRIVE JC96-02733A 1 O
11 MEA UNIT-COVER FRONT, USA JC97-01746A 1 O

1 1-1 COVER-M-FRONT JC63-00103A 1 O
1 1-2 ADJUST-M-MANUAL_L JC70-00302A 1 O
1 1-3 ADJUST RACK-M-MANUAL JC70-00304A 2 O
1 1-4 GEAR-RACK_PINION JC66-00387A 1 O
1 1-5 ADJUST-M-MANUAL_R JC70-00303A 1 O

12 MEAUNIT-CASSETTE, USA JC97-01750A 1 O
13 PBAMAIN-CONTROLLER GDI_1L JC92-01426A 1 O ML-1710A

PBA MAIN-CONTROLLER JC92-01424D 1 O ML-1750A

14 CBF HARNESS-ENGINE JC39-00240A 1 O ML-1710

CBF HARNESS-ENGINE JC39-00240B 1 O ML-1750

15 FAN-DC_HUMMINGBIRD JC31-00027A 1 O
16 MEAETC-TR JC97-01793A 1 O

16-1 ROLLER-TRANSFER ROLLER JC66-00528A 1 O
16-2 GEAR-TRANSFER JC66-00395A 1 O

16-3 PPR-SPACER_TR JC72-00851A 2 X
17 MEAUNIT-TONER CART_ DOM_1K * 1 X
18 CBF HARNESS-PANEL JC39-00244A 1 O
19 SHIELD-P-ENGINE * 1 X
20 BRACKET-P-INLET JC61-00601A 1 O

Main Assembly Parts List

SA : Service Available

O : Service available X : Service not available

8-4

EXPLODED VIEW & PA RTS LIST

Samsung Electronics

Service Manual

8.2 Frame Unit Assembly

0

1

2

4

3

5

6

7

61

12

6

9

53

9

51

13

14

15

16

17

57

18

19

20

20

21

22

23

24

25

26

37

31

27

28

29

29

30

58

58-1

58-2

58-3

58-4

58-5

58-6

58-6

58-4

40

41

56

42

44

53

45

46

47

48

59

59-1

59-2

59-3

59-4

50

52

52

54

55

11

10

8

35

36

Transfer Roller

38

60

39

43

32

34

33

62

49

49-3

49-2

49-1

8-5

Samsung Electronics

EXPLODED VIEW & PA RTS LIST

Service Manual

No. Description SEC.Code Q’ty SA Remark

0 ELA UNIT-FRAME LOWER, 110V JC96-02732A 1 O 110V
1 FRAME-M-BASE * 1 X
2 GUIDE-P-TR JC61-00607A 1 O
3 PLATE-P-SA W JC61-00604A 1 O
4 GUIDE-M-TR RIB JC61-00594A 1 O
5 GEAR-EXIT F/DOWN * 1 X
6 MEC-BEARING,EXIT * 2 X
7 ROLLER-EXIT F/DOWN JC66-00378A 1 O
8 SPRING-CS 6107-001163 4 O Spring Exit
9 PMO-GEAR_EXIT_DRV16 * 2 X
10 HOLDER-M-EXIT F/DOWN JC61-00582A 4 O
1 1 PMO-ROLLER_EXIT,MAIN * 4 X
12 PMO-ROLLER_EXIT,FR * 4 X
13 MEC-TERMINAL JC75-00049A 4 O
14 IPR-P-TERMINALCON JC70-00312A 3 O
15 IPR-P-TERMINALCR JC70-00313A 1 O
16 HOUSING-TERMINAL JC61-00592A 1 O
17 PMO-LOCKER CST JC72-00983A 2 O
18 PMO-ACTUATOR CVR OPEN JC72-00974A 1 O
19 PMO-PLATE GUIDE DEVE_R JC72-00985A 1 O
20 SPRING ETC-GUIDE DEVE * 2 X
21 IPR-P-GROUND_GUIDE PAPER JC70-00458A 1 O
22 PMO-PLATE GUIDE DEVE_L JC72-00984A 1 O
23 PMO-ACTUATOR FEED JC72-00976A 1 O
24 PMO-ACTUATOR EMPTY JC72-00975A 1 O
25 PMO-ACTUATOR MANUAL JC72-00977A 1 O
26 IPR-P-GROUND_EARTH TR * 1 X
27 SPRING-ETC 6107-001 162 1 O
28 ROLLER-FEED ROLLER 1 * 1 X
29 PMO-BUSHING FEED * 5 X
30 ROLLER-FEED JC66-00598A 1 O
31 SPRING-TS * 1 X Spring-act,Manual
32 IPR-P-EARTH TRANSFER JC70-00307A 1 O
33 HOLDER-PTL JC61-00583A 1 O
34 LENS-PTL JC67-00027A 1 O
35 BUSH-M-TR L JC61-00588A 1 O
36 SPRING ETC-TR LHAWK * 1 X
37 SPRING-TS * 1 X Spring-act,Feed
38 PMO-BUSHING_TR(L) JC72-00102A 1 O
39 IPR-P-GROUND_FUSER JC70-00310A 1 O
40 SHAFT-FEED IDLE JC66-00527A 1 O
41 BUSH-M-FEED IDLE * 2 X
42 SPRING ETC-TR * 2 X Spring Feed Idle
43 IPR-P_GROUND_DRIVE2 JC70-00335A 1 O
44 SPRING-TS 6107-001170 1 O Spring-cam Pick-up
45 CAM-M-PICK_UP JC66-00377A 1 O
46 IPR-P-GROUND_DRIVE JC70-00308A 1 O
47 SOLENOID-HB (PICK-UP) JC33-00009A 1 O
48 SOLENOID-HB (MANUAL) * 1 X

continue on the next page.

Frame Unit Assembly Parts List

SA : Service Available

O : Service available X : Service not available

8-6

EXPLODED VIEW & PA RTS LIST

Samsung Electronics

Service Manual

Frame Unit Assembly Parts List(Cont.)

SA : Service Available

O : Service available X : Service not available

No. Description SEC.Code Q’ty SA Remark

49 AS-GEAR PICK_UP JC81-01692A 1 O

49-1 PMO-GEAR PICK_UP B JC72-00980A 1 O
49-2 PMO-GEAR PICK_UPA JC72-00979A 1 O

49-3 SPRING-CS * 1 X Spring-Pick-up gear
50 BRACKET-P-FEED JC61-00602A 1 O
51 IPR-P-GROUND_TR JC70-0031 1A 1 O
52 SHAFT-FEED JC66-00398A 2 O
53 RING-CS * 3 X
54 GEAR-FEED 2 JC66-00394A 1 O
55 GEAR-IDLE 23 JC66-00396A 1 O
56 GUIDE-P-PAPER JC61-00718A 1 O
57 RMO-RUBBER_FOOT * 2 X
58 AS-PICK UP JC81-01693A 1 O

58-1 BUSH-M-PICK_UP L * 1 X

58-2 SHAFT -P-PICK_UP * 1 X

58-3 STOPPER-PICK_UP * 2 X

58-4 PMO-IDLE PICK_UP JC72-00982A 2 O

58-5 SPONGE-ROLLER PICK_UP JC72-01231A 1 O

58-6 BUSH-M-PICK_UP R JC61-00587A 1 O

58-7 HOUSING-M-PICK_UP JC61-00591A 1 O
59 MEAUNIT-CLUTCH JC97-01788A 1 O

59-1 GEAR-FEED 1 JC66-00393A 1 O

59-2 PMO-COLLAR_SPRING JC72-00978A 1 O

59-3 SPRING-TS * 1 X

59-4 PMO-HUB CLUTCH JC72-00981A 1 O
60 AS-FUSER 110V JC81-01689A 1 O 110V
61 RMO-RUBBER EXIT * 4 X
62 PBAMAIN-PTL * 1 X

8-7

Samsung Electronics

EXPLODED VIEW & PA RTS LIST

Service Manual

8.3 Drive Unit Assembly

0

1

2

3

4

4

5

6

7

8

9

HARNESS-MOTOR

5

No. Description SEC.Code Q’ty SA Remark

0 ELA UNIT-RX DRIVE JC96-02733A 1 O
1 BRACKET-P-GEAR 1400 * 1 X
2 GEAR-RDCN 53/26 * 1 X
3 GEAR-RDCN 113/33 * 1 X
4 GEAR-RDCN 57/18 * 2 X
5 RING-E * 2 X
6 BRACKET-P-MOTOR 1400 * 1 X
7 GEAR-RDCN 103/41 JC66-00390A 1 O
8 GEAR-RDCN 90/31 JC66-00392A 1 O
9 MOTOR STEP-HUMMINGBIRD JC31-00028A 1 O
10 PMO-IMPELLER_DRV * 1 X

Drive Unit Assembly Parts List

SA : Service Available

O : Service available X : Service not available

8-8

EXPLODED VIEW & PA RTS LIST

Samsung Electronics

Service Manual

8.4 Cassette Unit Assembly

0

1

2

3

4

5

5

6

7

8

9

10

11

15

16

18

12

13

14

17

8-9

Samsung Electronics

EXPLODED VIEW & PA RTS LIST

Service Manual

No. Description SEC.Code Q’ty SA Remark

0 MEA UNIT-CASSETTE, USA JC97-01750A 1 O
1 FRAME-M-CASSETTE

*

1X
2 PMO-EXTENSION LARGE JC72-00970A 1 O
3 PMO-EXTENSION SMALL JC72-00971A 1 O
4 PLA TE-P-KNOCK_UP

*

1X
5 SPRING-CS

*

2X
6 HOLDER-M-P AD

*

1X
7 SPRING ETC-EXIT ROLLFD

*

1X
8 ROLLER-M-IDLE FEED

*

2X
9 SPRING-ES

*

2X
10 PMO-PLATE_LOCKER

*

1X
11 SPRING ETC-LOCKER,PLATE

*

1X
12 ADJUST-M-CASSETTE_L JC70-00300A 1 O
13 ADJUST-M-CASSETTE_R JC70-00301A 1 O
14 GEAR-PINION

*

1X
15 INDICATOR-M-LEVER INDICATOR JC64-00040A 1 O
16 RPR-FRICTION PAD JC73-00140A 1 O
17 IPR-PLATE PAD

*

1X
18 RPR-PAD CASSETTE

*

3X

Cassette Unit Assembly Parts List

SA : Service Available

O : Service available X : Service not available

8-10

EXPLODED VIEW & PA RTS LIST

Samsung Electronics

Service Manual

8.5 Fuser Unit Assembly

0

1

2

3

4

5

32

32

6

33

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

31

22

23

24

25

26

27

30

28

29

8-11

Samsung Electronics

EXPLODED VIEW & PA RTS LIST

Service Manual

No. Description SEC.Code Q’ty SA Remark

O

AS-FUSER 110V JC81-01689A

1 O 1 10V

1 COVER-M-FUSER

*

1X

2 HOLDER-M-PLATE CLAW

*

4X

3 SPRING ETC-CLAW

*

4X

4 PMO-ROLLER EXIT

*

2X

5 SPRING ETC-FUSER EXIT

*

2X
6 THERMOSTAT -150 JC47-00005A 1 O
7 PMO-GEAR_EXIT_DRV16

*

1X
8 GEAR-IDLE 23

*

1X
9 RING-CS

*

1X
10 GEAR-RDCN 25/15 JC66-00397A 1 O
1 1 IPR-ELECTRODE_LAMP

*

1X
12 ELECTRODE-WIRE_L

*

1X
13 THERMISTOR-NTC 1404-001298 1 O
14 ELECTRODE-WIRE_R

*

1X
15 CBF HARNESS-FUSER 110V JC39-00239A 1 O White
16 GEAR-FUSER, Z37 JC66-00564A 1 O
17 BUSH-M-HR L

*

1X
18 ROLLER-HEA T JC66-00601A 1 O
19 BUSH-M-HR R JC61-00590A 1 O
20 LAMP-HALOGEN 4713-001155 1 O 110V
21 ROLLER-M-EXIT F/UP

*

1X
22 ROLLER-PRESSURE JC66-00600A 1 O
23 BEARING-PRESSURE/R

*

2X
24 SPRING-CS

*

2X
25 PMO-BUSHING TX

*

3X
26 HOLDER-ACTUA T OR

*

1X
27 PMO-ACTUA TOR_EXIT JC72-00987A 1 O
28 IPR-P-FRAME_FUSER

*

1X
29 GUIDE-M-INPUT

*

1X
30 SPRING-TS

*

1X
31 RMO-RUBBER_EXIT

*

2X
32 NUT-HEXAGON

*

5X
33 LABEL(P)-CAUTION, HOT_FUSER

*

1X

Fuser Unit Assembly Parts List

SA : Service Available

O : Service available X : Service not available

8-12

EXPLODED VIEW & PA RTS LIST

Samsung Electronics

Service Manual