Samsung ML-331x, ML-371x Service Manual

Service Manual

The keynote of Product

1. Speed

•ML-331x series : 31 ppm in A4 / 33 ppm in Letter

•ML-371x series : 35 ppm in A4 / 37 ppm in Letter

2. Processor

•ML-331x series : 375 MHz

•ML-371x series : 600 MHz

3. Printer Languages

•ML-331x series : SPL, PCL5e

•ML-371x series : PCL6/5e, PostsScript3, IBM

ProPrinter, EPSON

DIGITAL LASER PRINTER

ML-331x/ML-371x Series

ML-331xD/331xND/371xD/371xND/371xDW

4. Memory (Std / Max)

• ML-331x series : 64 MB / 64 MB

• ML-371xD : 64 MB / 320 MB

• ML-371xND/371xDW : 128 MB / 384 MB

5. Interfaces

• High Speed USB 2.0

• 10/100 BaseTX network connector (ML-331xND)

• 10/100/1000 BaseTX network connector (ML-371xND/371xDW)

• 802.11b/g/n wireless LAN (ML-371xDW)

• IEEE 1284 Parallel (Optional)

6. Toner Cartridge (Initial / Sales)

• ML-331x series : 2K / 2K, 5K

• ML-371x series : 5K / 2K, 5K, 10K

GSPN (Global Service Partner Network)

North America : service.samsungportal.com Latin America : latin.samsungportal.com CIS : cis.samsungportal.com

Europe : europe.samsungportal.com China : china.samsungportal.com Asia : asia.samsungportal.com

Mideast & Africa : mea.samsungportal.com

Samsung Electronics Co.,Ltd. September. 2010 Printed in Korea.

VERSION NO. : 1.00 CODE : 3310-00000E

Contents

chapter 1 Precautions

1.1Safety Warning …………………………………………………… 1-1

1.2Caution for safety ………………………………………………… 1-2

1.2.1Toxic material………………………………………………… 1-2

1.2.2 Electric Shock and Fire Safety Precautions ……………… 1-2

1.2.3Handling Precautions ……………………………………… 1-3

1.2.4Assembly / Disassembly Precautions …………………… 1-3

1.2.5 Disregarding this warning may cause bodily injury ………	1-4
1.3 ESD Precautions …………………………………………………	1-5

chapter 2 Product specifications and descriptions

2.1Speci cations …………………………………………………… 2-1

2.1.1Product Overview …………………………………………… 2-1

2.1.2Features by models ………………………………………… 2-2

2.1.3Speci cations………………………………………………… 2-3

2.1.4Model Comparison Table …………………………………… 2-10

2.2Product Description ……………………………………………… 2-11

2.2.1Front View …………………………………………………… 2-11

2.2.2Rear View …………………………………………………… 2-12

2.2.3Paper Path …………………………………………………… 2-13

2.2.4System layout ……………………………………………… 2-14

2.2.5Hardware con guration …………………………………… 2-21

2.2.6	Engine F/W Control Algorithm………………………………	2-39
2.2.7	S/W Descriptions ……………………………………………	2-42

chapter 3 Disassembly and Reassembly

3.1	General precautions on disassembly …………………………	3-1
3.2	Screws used in the printer ………………………………………	3-2

Contents

3.3Disassembly procedure ………………………………………… 3-3

3.3.1Cover ………………………………………………………… 3-3

3.3.2Main board …………………………………………………… 3-6

3.3.3HVPS board ………………………………………………… 3-6

3.3.4SMPS board ………………………………………………… 3-7

3.3.5 Laser Scanning Unit (LSU) ………………………………… 3-7

3.3.6Fuser unit …………………………………………………… 3-8

3.3.7Main drive unit ……………………………………………… 3-9

3.3.8Feed drive unit ……………………………………………… 3-10

3.3.9 Pick up/ Regi/ MP clutch …………………………………… 3-10

3.3.10Pick up roller ……………………………………………… 3-11

3.3.11Transfer roller ……………………………………………… 3-11

3.3.12MP unit ……………………………………………………… 3-12

3.3.13OPE board ………………………………………………… 3-13

3.3.14Bin-full sensor ……………………………………………… 3-13

3.3.15	Regi. / Feed / Empty sensor ………………………………	3-14
3.3.16	Cassette roller (Retard roller) ……………………………	3-15

chapter 4 Alignment and Troubleshooting

4.1 Alignment and Adjustments………………………………………	4-1
4.1.1 Control Panel…………………………………………………	4-1
4.1.2 Understanding The Status LED ……………………………	4-4
4.1.3 JAM Removal ………………………………………………	4-5
4.1.4 Useful menu item for service ………………………………	4-9
4.1.5 Periodic Defective Image……………………………………	4-11
4.1.6 Using the Easy Printer Manager program and smart panel …	4-12

4.1.7Updating Firmware ………………………………………… 4-14

4.1.8Tech Mode …………………………………………………… 4-17

4.2Troubleshooting…………………………………………………… 4-22

4.2.1	Procedure of Checking the Symptoms ……………………	4-22
4.2.2	Error Message and Troubleshooting ………………………	4-25

4.2.3Image Quality problem ……………………………………… 4-41

4.2.4Other errors ………………………………………………… 4-25

4.2.5Network problems…………………………………………… 4-41

Contents

chapter 5 System Diagram

5.1Block Diagram …………………………………………………… 5-1

5.2Connection Diagram……………………………………………… 5-3

chapter 6 Reference Information

6.1	Tool for Troubleshooting …………………………………………	6-1
6.2 Acronyms and Abbreviations ……………………………………		6-2

6.2.1Acronyms …………………………………………………… 6-2

6.2.2Service Parts ………………………………………………… 6-4

6.3 A4 ISO 19752 Standard Pattern…………………………………	6-8
6.3.1 A4 ISO 19752 Standard Pattern ……………………………	6-8
6.4 Selecting a location ………………………………………………	6-9

attached Parts Catalog (Exploded Views & Parts List)

1. Precautions

1. Precautions

In order to prevent accidents and to prevent damage to the equipment please read the precautions listed below carefully before servicing the printer and follow them closely.

1.1 Safety Warning

(1)Only to be serviced by appropriately quali ed service engineers.

High voltages and lasers inside this product are dangerous. This printer should only be serviced by a suitably trained and quali ed service engineer.

(2)Use only Samsung replacement parts

There are no user serviceable parts inside the printer. Do not make any unauthorized changes or

additions to the printer, these could cause the printer to malfunction and create electric shock or re hazards.

(3)Laser Safety Statement

The printer is certi ed in the U.S. to conform to the requirements of DHHS 21 CFR, chapter 1 Subchapter J for Class I(1) laser products, and elsewhere is certi ed as a Class I laser product conforming to the requirements of IEC 60825-1:1993 + A1:1997 + A2:2001. 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.

•Wavelength: 800 nm

•Beam divergence

-Paraller: 12 degrees

-Perpendicular: 35 degrees

•Maximum power or energy output: 15 mW

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:

Service Manual ML-331x/371x series

1-1

Samsung Electronics

1. Precautions

1.2 Caution for safety

1.2.1 Toxic material

This product contains toxic materials that could cause illness if ingested.

(1)If the LCD control panel is damaged it is possible for the liquid inside to leak. This liquid is toxic. Contact with the skin should be avoided, wash any splashes from eyes or skin immediately and contact your doctor. If the liquid gets into the mouth or is swallowed see a doctor immediately.

(2)Please keep Drum cartridge and Toner Cartridge away from children. The toner powder contained in the Drum cartridge and Toner Cartridge may be harmful and if swallowed you should contact a doctor.

1.2.2 Electric Shock and Fire Safety Precautions

Failure to follow the following instructions could cause electric shock or potentially cause a re.

(1) Use only the correct voltage, failure to do so could damage the printer and potentially cause a re or electric shock.

(2)Use only the power cable supplied with the printer. Use of an incorrectly speci ed cable could cause the cable to overheat and potentially cause a re.

(3)Do not overload the power socket, this could lead to overheating of the cables inside the wall and could lead to a re.

(4)Do not allow water or other liquids to spill into the printer, this can cause electric shock. Do not allow paper clips, pins or other foreign objects to fall into the printer these could cause a short circuit leading to an electric shock or re hazard.

(5)Never touch the plugs on either end of the power cable with wet hands, this can cause electric shock. When servicing the printer remove the power plug from the wall socket.

(6)Use caution when inserting or removing the power connector. The power connector must be inserted

completely otherwise a poor contact could cause overheating possibly leading to a re. When removing the power connector grip it rmly and pull.

(7)Take care of the power cable. Do not allow it to become twisted, bent sharply round corners or other wise damaged. Do not place objects on top of the power cable. If the power cable is damaged it could overheat and cause a re or exposed cables could cause an electric shock. Replace a damaged power cable immediately, do not reuse or repair the damaged cable. Some chemicals can attack the coating on

the power cable, weakening the cover or exposing cables causing re and shock risks.

(8)Ensure that the power sockets and plugs are not cracked or broken in any way. Any such defects should be repaired immediately. Take care not to cut or damage the power cable or plugs when moving the machine.

(9)Use caution during thunder or lightening storms. Samsung recommend that this machine be disconnected from the power source when such weather conditions are expected. Do not touch the machine or the power cord if it is still connected to the wall socket in these weather conditions.

(10)Avoid damp or dusty areas, install the printer in a clean well ventilated location. Do not position the machine near a humidi er. Damp and dust build up inside the machine can lead to overheating and cause a re.

(11)Do not position the printer in direct sunlight. This will cause the temperature inside the printer to rise

possibly leading to the printer failing to work properly and in extreme conditions could lead to a re.

(12)Do not insert any metal objects into the machine through the ventilator fan or other part of the casing, it could make contact with a high voltage conductor inside the machine and cause an electric shock.

Service Manual	1-2	Samsung Electronics

ML-331x/371x series

1. Precautions

1.2.3 Handling Precautions

The following instructions are for your own personal safety, to avoid injury and so as not to damage the printer

(1)Ensure the printer is installed on a level surface, capable of supporting its weight. Failure to do so could cause the printer to tip or fall.

(2)The printer contains many rollers, gears and fans. Take great care to ensure that you do not catch your ngers, hair or clothing in any of these rotating devices.

(3)Do not place any small metal objects, containers of water, chemicals or other liquids close to the printer

which if spilled could get into the machine and cause damage or a shock or re hazard.

(4)Do not install the machine in areas with high dust or moisture levels, beside on open window or close to a humidi er or heater. Damage could be caused to the printer in such areas.

(5) Do not place candles, burning cigarettes, etc on the printer, These could cause a re.

1.2.4 Assembly / Disassembly Precautions

Replace parts carefully, always use Samsung parts. Take care to note the exact location of parts and also cable routing before dismantling any part of the machine. Ensure all parts and cables are replaced correctly. Please carry out the following procedures before dismantling the printer or replacing any parts.

(1)Check the contents of the machine memory and make a note of any user settings. These will be erased if the mainboard or network card is replaced.

(2)Ensure that power is disconnected before servicing or replacing any electrical parts.

(3)Disconnect printer interface cables and power cables.

(4)Only use approved spare parts. Ensure that part number, product name, any voltage, current or temperature rating are correct.

(5) When removing or retting any parts do not use excessive force, especially when tting screws into plastic.

(6)Take care not to drop any small parts into the machine.

(7)Handling of the OPC Drum

-The OPC Drum can be irreparably damaged if it exposed to light.

Take care not to expose the OPC Drum either to direct sunlight or to uorescent or incandescent room lighting. Exposure for as little as 5 mins can damage the surface? photoconductive properties and will result in print quality degradation. Take extra care when servicing the printer. Remove the OPC Drum and store it in a black bag or other lightproof container. Take care when working with the covers(especially the top cover) open as light is admitted to the OPC area and can damage the OPC Drum.

-Take care not to scratch the green surface of OPC Drum Unit.

If the green surface of the Drum Cartridge is scratched or touched the print quality will be compromised.

1-3

Service Manual Samsung Electronics

ML-331x/371x series

1.Precautions

1.2.5Disregarding this warning may cause bodily injury

(1)Be careful with the high temperature part.

The fuser unit works at a high temperature. Use caution when working on the printer. Wait for the fuser to cool down before disassembly.

(2) Do not put nger or hair into the rotating parts.

When operating a printer, do not put hand or hair into the rotating parts (Paper feeding entrance, motor, fan, etc.). If do, you can get harm.

(3)When you move the printer.

This printer weighs 9kg (19.84 lbs) including toner cartridge and cassette. Use safe lifting and handling techniques. Use the lifting handles located on each side of the machine. Back injury could be caused if you do not lift carefully.

(4)Ensure the printer is installed safely.

The printer weighs 9kg (19.84 lbs), ensure the printer is installed on a level surface, capable of supporting its weight. Failure to do so could cause the printer to tip or fall possibly causing personal injury or damaging the printer.

(5)Do not install the printer on a sloping or unstable surface. After installation, double check that the printer is stable.

Service Manual	1-4	Samsung Electronics

ML-331x/371x series

1. Precautions

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 eld 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 classi ed as “anti-static” can generate electrical charges suf cient to damage ESDs.

5.Do not use Freon-propelled chemicals. When sprayed, these can generate electrical charges suf cient 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 oor, can generate static electricity suf cient to damage an ESD.

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Service Manual Samsung Electronics

ML-331x/371x series

2.Product specifications and descriptions

2.Product specifications and descriptions

2.1 Specifications

2.1.1 Product Overview

1. Speed

•ML-331x series : 31 ppm in A4 / 33 ppm in Letter

•ML-371x series : 35 ppm in A4 / 37 ppm in Letter

2. Processor

•ML-331x series : 375 MHz

•ML-371x series : 600 MHz

3. Printer Languages

•ML-331x series : SPL, PCL5e

•ML-371x series : PCL6/5e, PostsScript3, IBM ProPrinter, EPSON

4. Memory (Std / Max)

•ML-331x series : 64 MB / 64 MB

•ML-371xD : 64 MB / 320 MB

•ML-371xND/371xDW : 128 MB / 384 MB

5. Interfaces

•High Speed USB 2.0

•10/100 BaseTX network connector (ML-331xND)

•10/100/1000 BaseTX network connector (ML371xND/371xDW)

•802.11b/g/n wireless LAN (ML-371xDW)

•IEEE 1284 Parallel (Optional)

6. Toner cartridge (Initial / Sales)

•ML-3310 series : 2K / 2K, 5K

•ML-3710 series : 5K / 2K, 5K, 10K

Service Manual	2-1	Samsung Electronics

ML-331x/371x series

2.Product specifications and descriptions

2.1.2Features by models

	Features	ML-3310D	ML-3310ND	ML-3710D	ML-3710ND	ML-3710DW
		ML-3312D	ML-3312D	ML-3712D	ML-3712ND	ML-3712DW
	Hi-Speed USB 2.0	●	●	●	●	●
	IEEE 1284 Parallel	○	○	○	○	○
	Network Interface
	Ethernet 10/100 Base		●
	TX wired LAN
	Network Interface
	Ethernet 10/100/1000				●	●
	Base TX wired LAN
	Network Interface
	802.11b/g/n					●
	wireless LAN
	IPv6		●		●	●
	Eco printing	●	●	●	●	●
	Wi-Fi Protected Setup					●
	(WPS)
	Duplex (2-sided)	●	●	●	●	●
	printing
	Samsung Easy Printer	●	●	●	●	●
	Driver Manager
	Memory			○	○	○
	Tray 2		○	○	○	○
	SyncThru Web Service		●		●	●

( ●: Included, ○: Optional, Blank: Not available)

Service Manual	2-2	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2.1.3 Specifications

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

2.1.3.1 General Print Engine

	Item		ML-331x series	ML-371x series
Engine Speed		Simplex	Up to 31 ppm in A4 (33 ppm in Letter)	Up to 35 ppm in A4 (37 ppm in Letter)
		Duplex	Up to 15 ipm in A4 (16 ipm in Letter)	Up to 17 ipm in A4 (18 ipm in Letter)
Warmup time		From Sleep	15 sec	15 sec
FPOT		From Ready	As fast as 8 sec	As fast as 8 sec
		From Sleep	As fast as 15.5 sec	As fast as 15.5 sec
Resolution		-	Up to 1,200 x 1,200 dpi effective output	Up to 1,200 x 1,200 dpi effective output

2.1.3.2 Controller & S/W

	Item		ML-331x series	ML-371x series
Processor			Samsung 375 MHz	Samsung 600 MHz
Memory		Std.	64 MB	- 371xD : 64 MB
				- 371xND / 371xDW : 128 MB
		Max.	64 MB	- 371xD : 320 MB
				- 371xND / 371xDW : 384 MB
		Flash	- 331xD : 8 MB331xND : 16 MB	- 371xD : 16 MB
				- 371xND / 371xDW : 32 MB
Printer Languages			PCL5e, SPL	PostScript3, PCL6/5e, IBM
			IBM ProPrinter, EPSON	ProPrinter, EPSON
Fonts			93 scalable, 1 bitmap	93 scalable, 1 bitmap, 136 PostScript3
				fonts
Driver		Default Driver	SPL	PCL
		Install	SPL	PCL6 / PS3
		Supporting OS	Windows 2000/XP (32/64 bits) /	Windows 2000/XP (32/64 bits) /
			Vista (32/64 bits) /	Vista (32/64 bits) /
			2003 Server (32/64 bits) /	2003 Server (32/64 bits) /
			2008 Server(32/64 bits) /	2008 Server(32/64 bits) /
			7 (32/64 bits) /2008 Server R2	7 (32/64 bits) /2008 Server R2

Service Manual	2-3	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

Item		ML-331x series	ML-371x series
Driver	Supporting OS	Various Linux OS:	Various Linux OS:
(Continue..)	(Continue..)	Fedora Core 4, 5, 6	Fedora Core 4, 5, 6
		Fedora 7, 8, 9, 10, 11, 12	Fedora 7, 8, 9, 10, 11, 12
		RedHat Enterprise Linux WS 4, 5	RedHat Enterprise Linux WS 4, 5
		SuSE 10.0, 10.1	SuSE 10.0, 10.1
		openSuSE 10.2, 10.3, 11.0, 11.1, 11.2	openSuSE 10.2, 10.3, 11.0, 11.1, 11.2
		SuSE Linux Enterprise Desktop 10, 11	SuSE Linux Enterprise Desktop 10, 11
		Debian 4.0, 5.0	Debian 4.0, 5.0
		Ubuntu 5.04, 5.10, 6.04, 6.10, 7.04, 7.10,	Ubuntu 5.04, 5.10, 6.04, 6.10, 7.04, 7.10,
		8.04, 8.10, 9.04, 9.10	8.04, 8.10, 9.04, 9.10
		Mandriva 2005LE, 2006, 2007, 2007.1,	Mandriva 2005LE, 2006, 2007, 2007.1,
		2008, 2008.1, 2009, 2009.1	2008, 2008.1, 2009, 2009.1
		Mac OS 10.3 ~ 10.6	Mac OS 10.3 ~ 10.6
		Citrix Presentation Server	Citrix Presentation Server
		Windows Terminal Services	Windows Terminal Services
	WHQL	Windows 2000/XP(32/64bits)/	Windows 2000/XP(32/64bits)/
		Vista(32/64bits)/2003	Vista(32/64bits)/2003
		Server(32/64bits)/2008 Server(32/64bits)/	Server(32/64bits)/2008 Server(32/64bits)/
		7(32/64bit)/2008 Server R2(64bits)	7(32/64bit)/2008 Server R2(64bits)
	Compatibility	SPL: Win 2000/XP(32/64bits)/2003	SPL & PCL6: Win 2000/
		Server(32/64bits)/Vista(32/64bits)/2008 S	XP(32/64bits)/2003 Server(32/64bits)/
		erver(32/64bits)/7(32/64bits)/2008 Server	Vista(32/64bits)/2008
		R2	Server(32/64bits)/7(32/64bits)
			PS3: Win 2000/XP(32/64bits)/
			Vista(32/64bits)/2003
			server(32/64bits)/2008
			Server(32/64bits)/7 (32/64bits) PPD,
			Mac PPD, Linux PPD
Wired Network	Protocol	- 331xD : N/A	- 371xD : N/A
		- 331xND : TCP/IP, Ethertalk, SNMP,	- 371xND/ 371xDW : TCP/IP, Ethertalk,
		HTTP 1.1	SNMP, HTTP 1.1
	Supporting OS	- 331xD : N/A	- 371xD : N/A
		- 331xND :	- 371xND / 371xDW :
		Windows 2000/XP(32/64bits)/2003	Windows 2000/XP(32/64bits)/2003
		Server(32/64bits)/Vista(32/64bits)/2008	Server(32/64bits)/Vista(32/64bits)/2008
		Server(32/64bits)	Server(32/64bits)
		Mac OS 8.6~9.2, 10.1~10.5	Mac OS 8.6~9.2, 10.1~10.5
		Various Linux OS including Red Hat 8~9,	Various Linux OS including Red Hat 8~9,
		Fedora Core 1~4, Mandrake 9.2~10.1,	Fedora Core 1~4, Mandrake 9.2~10.1,
		and SuSE 8.2~9.2	and SuSE 8.2~9.2
		NetWare 5.x, 6.x (TCP/IP Only)	NetWare 5.x, 6.x (TCP/IP Only)
		Unix HP-UX	Unix HP-UX
Wireless	Protocol	N/A	- 371xD / 371xND : N/A
Network			- 371xDW : 802.11n

Service Manual	2-4	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

Item		ML-331x series	ML-371x series
Application	Smart Panel	SmartPanel for Windows/ Macintosh/	SmartPanel for Windows/ Macintosh/
		LINUX	LINUX
	Printer Setting	PSU for Windows/ Macintosh/LINUX	PSU for Windows/ Macintosh/LINUX
	Network	- 331xD : N/A	- 371xD : N/A
	Management	- 331xND : SyncThru Web Admin Service	- 371xND/ 371xDW : SyncThru Web
		5.0	Admin Service 5.0
	IP Setting	- 331xD : N/A	- 371xD : N/A
		- 331xND : SetIP	- 371xND/ 371xDW : SetIP
Interface
IEEE 1284 Parallel		Optional	Optional
USB		Hi-Speed USB 2.0	Hi-Speed USB 2.0
Wired Network		- 331xD : N/A	- 371xD : N/A
		- 331xND : Ethernet 10/100 Base TX	- 371xND / 371xDW : Ethernet
		(Internal)	10/100/1000 Base TX (Internal)
Wireless Network		N/A	371xDW only
User Interface
LCD		- 331xD : N/A	2-Line
		- 331xND :2-Line
LED		4EA: ECO(1), Power(1), Status(2)	- 371xD / 371xND : 4EA( ECO(1),
			Power(1), Status(2))
			- 3710xW : 5EA (ECO(1), Power(1),
			Status(2), WPS(1))
Key		- 331xD : 3EA (ECO, Power, Cancel)	- 371xD / 371xND : 8EA (5 Navigation
		- 331xND : 8EA (5 Navigation keys, ECO,	keys, ECO, Power, Cancel)
		Power, Cancel)	- 371xDW : 9EA (5 Navigation keys,
			ECO, WPS, Power, Cancel)

Service Manual	2-5	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2.1.3.3 Paper Handling

Item		ML-331x series	ML-371x series
Standard Capacity		250-sheet Cassette Tray,	250-sheet Cassette Tray, 50-sheet Multi
		1-sheet (331xD)/ 50-sheet (331xND) Multi	Purpose Tray @80g/
		Purpose Tray @80g/
Max. Capacity		- 331xD : 251 sheets @ 80g/	820 sheets @ 80g/
		- 331xND : 820 sheets @ 80g/
Printing	Max. Size	216 x 356 mm (8.5" x 14")	216 x 356 mm (8.5" x 14")
	Min. Size	76 x 127 mm (3.0" x 5.0")	76 x 127 mm (3.0" x 5.0")
Multi-purpose tray
Capacity	Plain Paper	- 331xD : 1 sheet @ 80g/	50 sheets @ 80g/
		- 331xND : 50 sheets @ 80g/
	Envelop	- 331xD : 1 sheet	5 sheets
		- 331xND : 5 sheets
Media sizes		A4, A5, A6, Letter, Legal, Folio, Oficio,	A4, A5, A6, Letter, Legal, Folio, Oficio,
		Executive, ISO B5, JIS B5, 3"x5",	Executive, ISO B5, JIS B5, 3"x5",
		Envelope(Monarch, No.10, DL, C5, C6),	Envelope(Monarch, No.10, DL, C5, C6),
		Custom	Custom
Media type		Plain, Thin, Thick, Thicker, Cotton, Colored,	Plain, Thin, Thick, Thicker, Cotton, Colored,
		Envelope, Transparency, Pre-Printed,	Envelope, Transparency, Pre-Printed,
		Recycled, Labels, Bond, Card stock,	Recycled, Labels, Bond, Card stock,
		Archive	Archive
Media weight		16~58lb (60 to 220g/ )	16~58lb (60 to 220g/ )
Sensing		- 331xD : N/A	Paper Empty
		- 331xND : Paper Empty
Standard Cassette Tray
Capacity		250 sheets @ 80g/	250 sheets @ 80g/
Media sizes		A4, A5, A6, Letter, Legal, Folio, Oficio,	A4, A5, A6, Letter, Legal, Folio, Oficio,
		Executive, ISO B5, JIS B5, Custom	Executive, ISO B5, JIS B5, Custom
Media types		Plain Paper, Thin, Thick, Recycled, Bond,	Plain Paper, Thin, Thick, Recycled, Bond,
		Cardstock, Archive	Cardstock, Archive
Media weight		16~43lb (60 to 163g/ )	16~43lb (60 to 163g/ )
Sensing		Paper Empty	Paper Empty
Optional Cassette Tray
Capacity		- 331xD : N/A	520 sheets @ 80g/
		- 331xND : 520 sheets @ 80g/
Media sizes		- 331xD : N/A	A4, A5, A6, Letter, Legal, Folio, Oficio,
		- 331xND : A4, A5, A6, Letter, Legal, Folio,	Executive, ISO B5, JIS B5
		Oficio, Executive, ISO B5, JIS B5
Media types		- 331xD : N/A	Plain Paper, Thin, Thick, Recycled, Bond,
		- 331xND : Plain Paper, Thin, Thick,	Cardstock, Archive
		Recycled, Bond, Cardstock, Archive

Service Manual	2-6	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

Item			ML-331x series	ML-371x series
Media weight			- 331xD : N/A	16~43lb (60 to 163g/ )
			- 331xND : 16~43lb (60 to 163g/ )
Sensing			- 331xD : N/A	Paper Empty
			- 331xND : Paper Empty
Output Stacking
Capacity		Face-Down	150 sheets @ 80g/	150 sheets @ 80g/
		Face-Up	1 sheet	1 sheet
Output Full sensing			Yes	Yes
Duplex
Supporting			Built-in	Built-in
Media sizes			A4, Letter, Oficio, Folio, Legal	A4, Letter, Oficio, Folio, Legal
Media types			Plain Paper, Thin, Thick, Recycled, Bond	Plain Paper, Thin, Thick, Recycled, Bond
Media weight			16~32lb (60 to 120g/ )	16~32lb (60 to 120g/ )
Printable Area
Non-Printable		Envelop	10mm(0.4") from edge(Top, Bottom, Left,	10mm(0.4") from edge(Top, Bottom, Left,
Area			Right)	Right)
		Other Media	4mm(0.16") from edge(Top, Bottom, Left,	4mm(0.16") from edge(Top, Bottom, Left,
			Right)	Right)

2.1.3.4 Consumables

	Item		ML-331x series	ML-371x series
Toner		Black	- Standard: Average Cartridge Yield 2K	- Standard: Average Cartridge Yield 2K
			standard pages.	standard pages.
			- High Yield: Average cartridge Yield 5K	- High Yield: Average cartridge Yield 5K
			standard pages.	standard pages.
			Declared cartridge yield in accordance	- Extra High Yield: Average cartridge
			with ISO/IEC 19752.	Yield 10K standard pages.
				Declared cartridge yield in accordance
				with ISO/IEC 19752.
		Key	Electronic key(CRUM) Only	Electronic key(CRUM) Only
		Life detect	Toner gauge sensor by dot count	Toner gauge sensor by dot count
Drum		Yield	N/A	N/A

Service Manual	2-7	Samsung Electronics

ML-331x/371x series

2.Product specifications and descriptions

2.1.3.5Reliability & Service

Item	ML-331x series	ML-371x series
Recommanded AMPV	1000 sheets/month	1500 sheets/month
Max AMPV	2500 sheets/month	3500 sheets/month
Max. Monthly Duty	50,000 sheets/month	80,000 sheets/month
MPBF	35,000 sheets	45,000 sheets
MTBF	35 months	35 months
MTTR	30 min.	30 min.
SET Life Cycle	170,000 sheets or 5 years (whichever	220,000 sheets or 5 years (whichever
	comes first)	comes first)

2.1.3.6 Maintenance part

Item	Part Code	Life
Transfer roller	JC66-02842A	Approx. 100,000 Pages
Fuser Unit	JC91-01023A (110V)	Approx. 90,000 Pages
	JC91-01024A (220V)
Pick-up Roller	JC73-00340A	Approx. 90,000 Pages
Retard Roller	JC90-01032A	Approx. 60,000 Pages

Service Manual	2-8	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2.1.3.7 Environment

Item			ML-331x series	ML-371x series
Operating Environment		Temperature	10C to 32C	10C to 32C
		Humidity	20% to 80%	20% to 80%
Acoustic Noise		Printing	51dBA	52dBA
Level(Sound Power/
		Standby	26 dBA	26 dBA
Pressure)
		Sleep	Back Ground Level	Back Ground Level
Power Consumption		Ready	Less than 55W	Less than 55W
		AVG.	Less than 550W	Less than 600W
		Max/Peak	Less than 600W	Less than 650W
		Sleep / Power Off	Less than 8W / Less than 0.4W	Less than 8W / Less than 0.4W
			(Conformity to EPA)	(Conformity to EPA)
Dimension (W x D x H)		SET	366 x 368 x 240.6	366 x 368 x 240.6
(W x D x H)
Weight		SET	9.0Kg	9.0Kg

2.1.3.6 Options

Item	ML-331x series	ML-371x series
Memory	N/A	256MB
Second Cassette	- 331xD : N/A	520-sheet Cassette Tray
	- 331xND : 520-sheet Cassette Tray
Wireless Network	N/A	N/A
Hard Disk	N/A	N/A

2.1.3.8 Others

	Item		ML-331x series	ML-371x series
Memory	Upgradable Mem. Slot	N/A		YES
	Upgradable Mem. Type	N/A		SODIMM
	Upgradable Mem. Unit	N/A		256MB
Sensor	Paper Empty	YES		YES
	Paper Size	NO		NO
	Media Type	NO		NO
	Paper Full	YES		YES

Service Manual	2-9	Samsung Electronics

ML-331x/371x series

2.Product specifications and descriptions

2.1.4Model Comparison Table

Samsung	Samsung	HP	Lexmark
ML-3710 series	ML-3310 series	P2050 series	E360dn

Image

	Speed	35 ppm (A4)	31 ppm (A4)	33 ppm (A4)	38 ppm (A4)
		37 ppm (Letter)	33 ppm (Letter)
	Processor	600 MHz	375 MHz	600 MHz	400 MHz
	Memory	371xD (64/320 MB)		P2055dn (128/384 MB)
		371xND/DW	64 / 64 MB		32 / 288 MB
	(Std/Max)			P2055d (64/320MB)
		(128/384MB)
	Emulation	PCL6/5e, PS3	SPL, PCL5e	PCL6	PCL6/PS3
	MP/Cassette	50 / 250	1 / 250 (331xD)	50 / 250	50 / 250
			50 / 250 (331xND)
	SCF	520 sheets	N/A (331xD)	500 sheets	550 sheets
			/ 520 sheets (331xND)
	Duplex	Std.	Std.	Std.	Std.
	Toner Yield	2K/ 5K / 10K	2K / 5K	2.3K/ 6.5K	3.5K / 9K
		- High speed USB 2.0	- High speed USB 2.0	- High speed USB 2.0	- High speed USB 2.0
		- Ethernet 10/100/1000
	Interface		- Ethernet 10/100 Base	- Ethernet 10/100/1000	- Ethernet 10/100 Base
		Base TX (371xND/DW)
			TX (331xND)	Base TX (P2055dn)	TX
		- Wireless LAN (371xDW)
	Noise	52dB	51dB	55dB	53dB

Service Manual	2-10	Samsung Electronics

ML-331x/371x series

2.Product specifications and descriptions

2.2Product Description

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

2.2.1 Front View

	X			`
			Y
	_			XW
	^		Z
			[	XX
	]
	\
1	Output tray	7	Tray 1
2	Control panel	8	Multi-purpose tray
3	Control board cover	9	Multi-purpose tray paper extension
4	Front cover	10	Paper width guides on a multi-purpose tray
5	Paper level indicator	11	Output support

6Optional tray 2a a. Optional device.

Service Manual	2-11	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2.2.2 Rear View

1

2

3

4

5

6 7

1	Network Porta	5	Power receptacle
2	USB port	6	Duplex unit
3	Output 5V	7	Rear cover

4Power Switch (Only Korea)

a. Available only with models that support network connection.

Service Manual	2-12	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2.2.3 Paper Path

[1] Simplex		[2] Duplex		[3] MP

Service Manual	2-13	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2.2.4 System layout

This model is consisted of the Engine parts and F/W. The engine parts is consisted of the mechanical parts comprising Frame, Feeding, Developing, Driving, Transferring, Fusing, Cassette and H/W comprising the main control board, power board, operation panel, PC Interface.

	11
		1
10
9		2	4
		3
		6	5
	8
			7

1	LSU	7	Cassette
2	Cartridge	8	Duplex
3	Regi roller	9	Fuser
4	MP	10	Exit roller1
5	Feed roller	11	Exit roller2
6	Pick up roller

Service Manual	2-14	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2.2.4.1 Feeding Part

It is consists of a basic cassette, an MP tray for supplying different types of media (envelope, label, special paper) and parts related to paper transferring.

1) Basic cassette

The paper trays consist of the Main trays, Optional trays (SCF), and one Multi-Purpose (MP) tray.

The basic cassette is located on front side of the machine and allows feeding of common paper. Paper size is set using the Size Guides in each tray. Adjust the Paper length/width guides to match the paper

size.

3

1

LGL

A4

LTR

2

1Paper length guide

2Support guide

3Paper width guide

2) Pick up / Retard Roller

When pickup takes place, the pickup roller rotates to separate and transport the paper.

The pickup roller rotates when the pickup clutch is activated. The retard roller serve to make sure

that a single sheet of paper is moved to the paper path, and the paper is moved as far as the registration roller by the work of the feed roller. The following is a diagram of the pickup section:

Pickup Roller
Feed Roller	Regi. Roller

Retard Roller

Service Manual	2-15	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

3) Registration roller

It has a paper arranging function, paper transferring function, paper detecting function, jam removing function, and so on.

4) MP tray

The multi-purpose tray can hold special sizes and types of print material, such as postcards, note cards, and envelopes. It is useful for single page printing on letterhead or colored paper. It uses 3 rollers feeding method to feed 50 sheets (371x series / 331xND) or 1 sheet (331xD) of general papers.

5) Duplex unit

It has paper transferring function, paper guide function, jam removing function.

It is designed for basic attachment, and the duplex feeding takes a side feeding method. Usable

papers are A4, letter, and legal size paper. For removing a jam occurred in a front part, it is designed to open a cassette and a guide.It is designed to open a rear cover to remove a jam in a rear part. If a face up tray is open, the duplex option cannot be used.

6) SCF (Second Cassette Feeder)

It is the same method with the main cassette, and the capacity is 520 sheets.

It has a separate driving mechanism. It is designed for a common use with a main cassette.

Service Manual	2-16	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2.2.4.2 Imaging unit

1) Printing process overview

LSU

Toner Cartridge

OPC Drum

Transfer Roller

This mono printing system includes the LSU with a laser beams, a toner cartridge and transfer roller.

This machine uses single toner cartridge and dual laser beams for mono printing. The toner cartridge consists of Drum unit and Development unit. The Drum unit has an OPC drum, cleaning blade.

The OPC drum is charged with a negative voltage by the scorotron and is exposed by the light from the LSU (Laser Scanning unit). The light produced by a laser creates a latent image by discharging on the surface

of the OPC drum. The negatively charged toners are attracted to the latent image due to and electric filed. The toners(real image) on the OPC drum are moved to the transfer media by the positive bias applied to the transfer roller.

1.Charging the OPC drum: The scorotron gives the drum negative charges.

2.Laser exposure: Light produced by a laser diode irradiates the charged OPC through the lens and mirrors.

3.Development: This machine uses a dual-component development system . The magnetic roller carries negatively

charged toner to the latent image on the drum surface.

4.Transfer: The transfer rollers opposite the OPC drums transfer toner from the drums to the transfer media (e.g. paper, OHP film, etc).

5.Cleaning for OPC drum: The cleaning blade removes remaining toners on the drum surface after image transfer

to the paper.

Service Manual	2-17	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2) Toner cartridge

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

•Operation condition : Temp 10~30 , Humidity 20~85% RH

•Developing Method : Non magnetic 1 element contacting method

•Toner : Non magnetic 1 element shatter type toner

•The life span of toner (ISO 19752 pattern / A4 standard) → Initial toner : 2K (331x series) / 5K (337x series)

→ Sales toner : 2K / 5K / 10K(only 337x series)

•Toner Residual Sensor : Dot count with CRUM(CRU Monitor)

•OPC Cleaning : Collect the toner by using cleaning blade

•Handling of wasted toner : Collect the wasted toner in the cleaning frame by using cleaning blade

•OPC Drum Protecting Shutter : None

•Classifying device for toner cartridge: ID is classified by CRUM.

	Charge Roller		Supply Roller
	Drum OPC		Charge Cleaning Roller
	Cleaning Blade		Agitator 1
	Doctor Blade		Agitator 2

Developer Roller

Service Manual	2-18	Samsung Electronics

ML-331x/371x series

2. Product specifications and descriptions

2.2.4.3 Fuser unit

It is consisted of a halogen lamp, heat roller, pressure roller, thermistor and thermostat. It sticks the toner on a paper by heat and pressure to complete the printing job.

1) Thermostat

When a heat lamp is overheated, a Thermostat cuts off the main power to prevent overheating.

-Thermostat Type : NonContact type THERMOSTAT

-Control Temperature : 170 ± 5

2) Thermistor

It is a temperatrue detecting sensor.

- Temperature Resistance : 7 (180 )

3) Heat roller

The heat roller transfers the heat from the lamp to apply a heat on the paper.

The surface of a heat roller is coated with Teflon, so toner does not stick to the surface.

4) Pressure roller

A pressure roller mounted under a heat roller is made of a silicon resin, and the surface also is coated with Teflon. When a paper passes between a heat roller and a pressure roller, toner adheres to the surface of a paper permanently.

5) Halogen Lamp

-Voltage 120 V : 115 ± 5 % 220 V : 230 ± 5 %

-Capacity : 850 Watt ± 25 W

Service Manual	2-19	Samsung Electronics

ML-331x/371x series

2.Product specifications and descriptions

2.2.4.4LSU (Laser Scanning Unit)

It is the core part of the LBP which switches from the video data received to the controller to the electrostatic latent image on the OPC drum by controlling laser beam, exposing OPC drum, and turning principle of polygon mirror. The OPC drum is turned with the paper feeding speed. The /HSYNC signal is created when the laser beam from LSU reaches the end of the polygon mirror, and the signal is sent to the controller.

The controller detects the /HSYNC signal to adjust the vertical line of the image on paper. In other words, after the /HSYNC signal is detected, the image data is sent to the LSU to adjust the left margin on paper. The one side of the polygon mirror is one line for scanning.

OPC Drum

Photo Diode

Polygon Mirror

Polygon Motor

LD Driver circit

Motor Driver

LD(Laser Diode)

Protector panel

Service Manual	2-20	Samsung Electronics

ML-331x/371x series