Samsung ML-4550 Series User manual

DIGITAL LASER PRINT CONTENTS
[The keynote of Product]
- Series Model: ML-4550 / 4551N / 4551ND
- High speed Laser Printer:
Up to 43 ppm in 4 (45 ppm in Letter),
Duplex: 29 ipm ( 4); 30 ipm (Letter)
- Resolution: Up to 1200 x 1200 dpi
- Marvell 500Mhz
- Memory: 128 MB (Max. 512 MB)
128, or 256 MB optional memory available.
Use only the Samsung-approved DIMM.
128 MB: ML-MEM150, 256 MB: ML-MEM160
- Option:
ML-4550:500-sheet trays, ethernet 10/100 Base
TX wired L N, ethernet 10/100 Base
hard disk, duplex unit, DIMM
- Toner cartridge:
Starter: 10K or 20K pages
Consumable: 10K or 20K pages
- Duty cycle: Monthly Up to 150,000 pages
Manual
SERVICE
DIGITAL LASER PRINT
ML-4550 Series
ML-4550/XEU
Basic Model :ML-4550

ELECTRONICS
Samsung Electronics Co.,Ltd. Mar. 2006
Printed in Korea.
VERSION NO. : 1.00 CODE : JC-0168F
* This service manual is a property of Samsung Electronics Co., Ltd.
Any unauthorized use of Manual can e punished under applica le
international and/or domestic law.

Contents
1 Precautions
1.1 Safety Warning 1-1
1.2 Caution for safety 1-2
1.3 ESD Precautions 1-5
2 Product Specifications
2.1 Product Overview 2-1
2.2 Specifications 2-1
2.3 Model Comparison Table 2-6
3 Summary of Product
3.1 Printer Components 3-1
3.2 System Layout 3-7
3.3 Engine H/W Specifications 3-11
4 Alignment and Adjustments
4.1 How to use EDC (Engine Diagnostic Control) Mode 4-1
4.2 Paper Path 4-10
4.3 Sample Pattern 4-17
4.4 Periodic Defective Image 4-18
4.5 Error Messages 4-19

Continue
5 Disassembly and Reassembly
5.1 General Precautions on Disassembly 5-1
5.2 Transfer Roller 5-2
5.3 MPF ss’y 5-3
5.4 Holder Pad ss'y 5-4
5.5 Retard ss'y 5-5
5.6 Feed2 Idle Unit 5-6
5.7 Cover Right 5-7
5.8 Main PB 5-8
5.9 Main Drive ss'y 5-9
5.10 DEVE Drive ss'y 5-10
5.11 Connector PB 5-11
5.12 Solenoid 5-12
5.13 Rear Cover 5-13
5.14 Cover Left 5-14
5.15 Top Cover 5-15
5.16 Open Cover 5-16
5.17 Inner Cover 5-17
5.18 Fuser ss'y 5-18
5.19 Duplex Solenoid ss'y 5-20
5.20 Exit Roller 5-21
5.21 LSU 5-22
5.22 DC Fan 5-23
5.23 Toner Sensor PB 5-24
5.24 REGI ss'y 5-25
5.25 MP Pick Up ss'y 5-26
5.26 Pick Up & Feed2 ssy 5-28
5.27 Engine Shield 5-31

Continue
6 Troubleshooting
6.1 The cause and solution of Bad image 6-1
6.2 The cause and solution of the bad discharge 6-8
6.3 The cause and solution of the malfunction 6-13
6.4 Maintaining the toner cartridge 6-17
6.5 The cause and solutions of bad environment of the software 6-22
7 Exploded Views & Parts List
7.1 Main ssembly 7-2
7.2 Cover ssembly 7-3
7.3 Frame ssembly 7-4
7.4 Fuser Unit 7-6
7.5 REGI ssembly 7-7
7.6 Main Motor ssembly 7-8
7.7 Deve Motor ssembly 7-9
7.8 Exit Sorenoid ssembly 7-10
7.9 Cassette ssembly 7-11
7.10 Duplex Unit 7-12
7.11 SCF Unit 7-13
8 Block diagram
8.1 System Block Diagram 8-1
9 Connection Diagram
9.1 Connection Diagram 9-1

Continue
10 Schematic Diagram
10.1 Main Board 10-1
10.2 DIMM board 10-17
10.3 CRUM board 10-19
10.4 EMPTY board 10-20
10.5 HVPS 10-21
10.6 Panel 10-25
10.7 SCF 10-26
10.8 Toner sensor 10-29
10.9 HDD.eps 10-30
11 Reference Information
11.1 Troubleshooting Tools 11-1
11.2 cronyms and bbreviations 11-2
11.3 Select a location for the printer 11-4
11.4 Sample Tests Patterns 11-5

Exploded Views & Parts List
Service Manual
7-1
Samsung Electronics
7.1 Main Assembly p.7-2
7.2 Cover Assembly p.7-3
7.3 Frame Assembly p.7-4
7.4 Fuser Unit p.7-6
7.5 REGI Assembly p.7-7
7.6 Main Motor Assembly p.7-8
7.7 Deve Motor Assembly p.7-9
7.8 Exit Sorenoid Assembly p.7-10
7.9 Cassette Assembly p.7-11
7.10 Duplex Unit p.7-12
7.11 SCF Unit p.7-13
7. Exploded Views and Parts List (ML-4550/XEU)
Contents

Service Manual
Exploded Views & Parts List
7-2
Samsung Electronics
7.1 Main Assembly
0
2
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4
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3-1
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SCF
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Exploded Views & Parts List
Service Manual
7-3
Samsung Electronics
7.2 Cover Assembly
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Service Manual
Exploded Views & Parts List
7-4
Samsung Electronics
7.3 Frame Assembly(1/2)
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1
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