DIGITAL LASER PRINT CONTENTS
[The keynote of Product]
- Series Model: ML-4550 / 4551N / 4551ND
- High speed Laser Printer:
Up to 43 ppm in A4 (45 ppm in Letter),
Duplex: 29 ipm (A4); 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 LAN, 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
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 be punished under applicable
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 T able 2-6
3. Summary of Product
3.1 Printer Components 3-1
3.2 System Layout 3-7
3.3 Engine H/W Specifications 3-1 1
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 Ass’y 5-3
5.4 Holder Pad Ass'y 5-4
5.5 Retard Ass'y 5-5
5.6 Feed2 Idle Unit 5-6
5.7 Cover Right 5-7
5.8 Main PBA 5-8
5.9 Main Drive Ass'y 5-9
5.10 DEVE Drive Ass'y 5-10
5.1 1 Connector PBA 5-11
5.12 Solenoid 5-12
5.13 Rear Cover 5-13
5.14 Cover Left 5-14
5.15 T op Cover 5-15
5.16 Open Cover 5-16
5.17 Inner Cover 5-17
5.18 Fuser Ass'y 5-18
5.19 Duplex Solenoid Ass'y 5-20
5.20 Exit Roller 5-21
5.21 LSU 5-22
5.22 DC Fan 5-23
5.23 T oner Sensor PBA 5-24
5.24 REGI Ass'y 5-25
5.25 MP Pick Up Ass'y 5-26
5.26 Pick Up & Feed2 Assy 5-28
5.27 Engine Shield 5-31
Continue...
6. T roubleshooting
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 Assembly 7-2
7.2 Cover Assembly 7-3
7.3 Frame Assembly 7-4
7.4 Fuser Unit 7-6
7.5 REGI Assembly 7-7
7.6 Main Motor Assembly 7-8
7.7 Deve Motor Assembly 7-9
7.8 Exit Sorenoid Assembly 7-10
7.9 Cassette Assembly 7-1 1
7.10 Duplex Unit 7-12
7.1 1 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 T oner sensor 10-29
10.9 HDD.eps 10-30
11. Reference Information
1 1.1 Troubleshooting Tools 1 1-1
1 1.2 Acronyms and Abbreviations 1 1-2
1 1.3 Select a location for the printer 1 1-4
1 1.4 Sample T ests Patterns 1 1-5
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
1
4
3
3-1
3-2
3-3
3-5
3-4
3-6
4-1
4-2
7
8
8-1
8-2
8-3
8-4
9
9-1
9-2
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20
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29
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31
30
30
32
34
35
SCF
37
39-2
39-1
39(Network only)
24
5
6
Exploded Views & Parts List
Service Manual
7-3
Samsung Electronics
7.2 Cover Assembly
0
1
2
4
5
6
6-1
6-10
6-2
6-3
6-5
6-4
6-6
6-7
6-8
6-9
6-9
7 (N/A : ML-4551ND)
7-2
7-1
1-12
1-13
1-10
1-11
1-9
1-17
1-5
1-2
1-3
1-8
1-7
1-6
1-4
1-16
1-14
1-1
1-15
1-18
3-3
3-1
3
3-2
Service Manual
Exploded Views & Parts List
7-4
Samsung Electronics
7.3 Frame Assembly(1/2)
43
1
2
2-1
2-2
2-2
2-4
2-3
2-4-1
2-4-2
2-4-3
3
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-7
3-7
4
4-1
4-2
4-3
4-4
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4-6
4-7
4-8
5
5-1
5-2
5-3
5-4
6
8
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11
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39
45
0
43
Exploded Views & Parts List
Service Manual
7-5
Samsung Electronics
Frame Assembly(2/2)
0
47
48
49
50
50
41
49
48-2
48-1
48-3
48-4
48-5
48-6
48-7
48-8
48-9
50-1
50-2
50-3
50-4
50-9
50-5
50-6
50-7
50-6
51
52
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54
59-9
59-6
58
59-10
59-11
59-8
59
60
59-4
59-5-1
59-5-2
59-5
59-7
55
56
59-1
59-2-1
59-2-2
59-2-3
59-2
59-3
57
60-1
60-2
60-5
60-3
61
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100
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99
49-1
49-2
49-3
49-4
49-5
60-4
49-7
49-8
49-9
49-9
49-13
49-10
49-10
49-11
49-12
60-4
49-7
47-1
47-2
47-3
47-5
47-4
60-4
60-6
60-6-1
60-6-3
60-6-2