HP LaserJet Pro 200 color M251 Troubleshooting Manual

LASERJET PRO 200 COLOR

Troubleshooting Manual

M251n

M251nw

HP LaserJet Pro 200 color M251 Series Printer

Troubleshooting Manual

Copyright and License

© 2012 Copyright Hewlett-Packard

Development Company, L.P.

Reproduction, adaptation, or translation without prior written permission is prohibited, except as allowed under the copyright laws.

The information contained herein is subject to change without notice.

The only warranties for HP products and services are set forth in the express warranty statements accompanying such products and services. Nothing herein should be construed as constituting an additional warranty. HP shall not be liable for technical or editorial errors or omissions contained herein.

Part number: CF146-90968

Edition 1, 9/2012

Trademark Credits

Microsoft®, Windows®, Windows® XP, and Windows Vista® are U.S. registered trademarks of Microsoft Corporation.

ENERGY STAR and the ENERGY STAR mark are registered U.S. marks.

Conventions used in this guide

TIP: Tips provide helpful hints or shortcuts.

NOTE: Notes provide important information to explain a concept or to complete a task.

CAUTION: Cautions indicate procedures that you should follow to avoid losing data or damaging the product.

WARNING! Warnings alert you to specific procedures that you should follow to avoid personal injury, catastrophic loss of data, or extensive damage to the product.

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Table of contents

1 Theory of operation ..........................................................................................................	1
Basic operation ........................................................................................................................	2
Major product systems ...............................................................................................	2
Product components ..................................................................................................	3
Sequence of operation ...............................................................................................	4
Engine control system ...............................................................................................................	5
DC controller ............................................................................................................	6
Low-voltage power supply ..........................................................................................	7
High-voltage power supply .........................................................................................	8
Laser/scanner system ...............................................................................................................	9
Laser failure detection ................................................................................................	9
Image-formation system ...........................................................................................................	10
Image-formation process ..........................................................................................	10
Latent-image formation stage ....................................................................................	11
Step 1: primary charging ..........................................................................	12
Step 2: laser-beam exposure .....................................................................	12
Developing stage ....................................................................................................	12
Step 3: development .................................................................................	13
Transfer stage .........................................................................................................	14
Step 4: primary transfer ............................................................................	14
Step 5: secondary transfer .........................................................................	14
Step 6: separation from the ITB ..................................................................	15
Fusing stage ...........................................................................................................	15
Step 7: fusing ..........................................................................................	15
ITB cleaning stage ...................................................................................................	16
Step 8: ITB cleaning .................................................................................	16
Drum cleaning stage ................................................................................................	17
Step 9: drum cleaning ..............................................................................	17
Pickup-and-feed system ...........................................................................................................	18
Jam detection .........................................................................................................	19
USB flash drive ......................................................................................................................	20

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2 Solve problems ...............................................................................................................	21
Solve problems checklist .........................................................................................................	22
Menu map ............................................................................................................................	24
Print a menu map (LCD control panel) ........................................................................	24
Print a menu map (touchscreen control panel) .............................................................	24
Troubleshooting process ..........................................................................................................	25
Pre-troubleshooting checklist .....................................................................................	25
Power-on checks .....................................................................................................	27
Tools for troubleshooting .........................................................................................................	28
Component diagnostics ............................................................................................	28
LED diagnostics ........................................................................................	28
Network LEDs ...........................................................................	28
Control panel LEDs ....................................................................	29
Control-panel diagnostics ..........................................................................	30
Engine diagnostics ...................................................................................	30
Engine test ................................................................................	30
Diagrams ...............................................................................................................	31
Plug/jack locations ...................................................................................	31
DC controller PCA ....................................................................................	32
Locations of major components ..................................................................	34
General timing chart .................................................................................	36
General circuit diagram ............................................................................	37
Internal print-quality test pages ..................................................................................	38
Interpret the Print Quality Page ...................................................................	38
Print a cleaning page ...............................................................................	38
Print a cleaning page (LCD control panel) ....................................	39
Print a cleaning page (touchscreen control panel) ..........................	39
Configuration page ..................................................................................	39
Print a configuration page (LCD control panel) ..............................	39
Print a configuration page (touchscreen control panel) ...................	40
Print-quality troubleshooting tools ..............................................................................	41
Repetitive image defects ............................................................................	41
Calibrate the product to align the colors ......................................................	41
Control-panel menus ................................................................................................	42
Setup Menu .............................................................................................	42
HP Web Services ......................................................................	42
Reports menu ............................................................................	43
Self Diagnostics menu ................................................................	44
System Setup menu ....................................................................	45
Service menu ............................................................................	48
Network Setup menu .................................................................	50

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Quick Forms menu ....................................................................	51
Function specific menus .............................................................................	52
Apps .......................................................................................	52
USB Flash Drive ........................................................................	52
Interpret control panel messages ...............................................................................	53
Control panel message types .....................................................................	53
Control panel messages ............................................................................	53
10.X00Y Supply Error ................................................................	53
49 Error, Turn off then on ...........................................................	54
50.x Fuser Error ........................................................................	54
51.XX Error ..............................................................................	54
54.XX Error ..............................................................................	54
55.X Error ................................................................................	55
57 Fan Error, Turn off then on .....................................................	55
59.X Error ................................................................................	55
79 Error Turn off then on ............................................................	56
Black Cartridge Low ..................................................................	56
Black in wrong position ..............................................................	56
Black Very Low .........................................................................	56
Cleaning ..................................................................................	57
Cyan Cartridge Low ..................................................................	57
Cyan in wrong position ..............................................................	57
Cyan Very Low .........................................................................	57
Device error, press OK ..............................................................	58
Door open ................................................................................	58
Genuine HP supply installed .......................................................	58
Incompatible <color> .................................................................	58
Incorrect supplies ......................................................................	58
Install <color> cartridge .............................................................	59
Invalid driver Press [OK] ............................................................	59
Jam in Tray 1, Clear jam and then press OK ................................	59
Load tray 1 Press [OK] for available media ..................................	59
Load Tray 1 <TYPE> <SIZE>, Press OK to use available media .......	59
Load Tray 1, <PLAIN> <SIZE> / Cleaning mode, OK to start .........	59
Magenta Cartridge Low .............................................................	60
Magenta in wrong position ........................................................	60
Magenta Very Low ....................................................................	60
Manual Duplex Load Tray 1, Press OK ........................................	60
Memory is low. Press OK. ..........................................................	61
Misprint, Press OK .....................................................................	61
Print failure, press OK. If error repeats, turn off then on. .................	61

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Rear door open .........................................................................	61
Remove shipping lock from <color> cartridge ...............................	62
Remove shipping locks from cartridges ........................................	62
Replace <color> .......................................................................	62
Supplies low .............................................................................	62
Unexpected size in tray 1 Load <size> Press [OK] ........................	62
Unsupported <color> Press [OK] to continue ..............................	0
Used <color> in use ...............................................................	0
Used <color> installed, to accept press OK ...............................	0
Used supplies in use ...............................................................	0
Yellow Cartridge Low .............................................................	0
Yellow in wrong position .........................................................	0
Yellow Very Low ....................................................................	0
Event-log messages ...............................................................................................	0
Clear jams .........................................................................................................................	0
Jam locations .......................................................................................................	0
Clear jams in the paper input tray ..........................................................................	0
Clear jams from the output bin ...............................................................................	0
Clear jams from the rear door ................................................................................	0
Solve paper-handling problems .............................................................................................	0
The product picks up multiple sheets of paper ..........................................................	0
The product does not pick up paper .......................................................................	0
Solve image quality problems ...............................................................................................	0
Use the correct paper type setting in the printer driver ..............................................	0
Change the paper type setting for Windows .............................................	0
Change the paper type setting for Mac ....................................................	0
Adjust color settings in the printer driver ..................................................................	0
Change the color theme for a print job ....................................................	0
Change the color options .......................................................................	0
Use paper that meets HP specifications ...................................................................	0
Print a cleaning page ...........................................................................................	0
Print a cleaning page (LCD control panel) ................................................	0
Print a cleaning page (touchscreen control panel) ......................................	0
Calibrate the product to align the colors ..................................................................	0
Check the toner cartridges .....................................................................................	0
Print the Supplies Status page .................................................................	0
Inspect the print cartridge for damage .....................................................	0
Repeating defects ..................................................................................	0
Use the printer driver that best meets your printing needs ..........................................	0
Solve performance problems ................................................................................................	0
Factors affecting print performance ........................................................................	0

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Print speeds .............................................................................................	84
The product does not print or it prints slowly ...............................................................	85
The product does not print .........................................................................	85
The product prints slowly ...........................................................................	86
Solve product connectivity problems .........................................................................................	87
Solve direct-connect problems ...................................................................................	87
Solve network problems ...........................................................................................	87
Poor physical connection ...........................................................................	87
The computer is using the incorrect IP address for the product ........................	87
The computer is unable to communicate with the product ..............................	88
The product is using incorrect link and duplex settings for the network ............	88
New software programs might be causing compatibility problems ..................	88
The computer or workstation might be set up incorrectly ................................	88
The product is disabled, or other network settings are incorrect ......................	88
Solve wireless network problems ...............................................................................	89
Wireless connectivity checklist ...................................................................	89
The control panel displays the message: The wireless feature on this product
has been turned off ..................................................................................	90
The product does not print after the wireless configuration completes ..............	90
The product does not print, and the computer has a third-party firewall
installed ..................................................................................................	90
The wireless connection does not work after moving the wireless router or
product ...................................................................................................	90
Cannot connect more computers to the wireless product ................................	91
The wireless product loses communication when connected to a VPN .............	91
The network does not appear in the wireless networks list .............................	91
The wireless network is not functioning ........................................................	92
Service mode functions ...........................................................................................................	93
Service menu ..........................................................................................................	93
Service menu settings ................................................................................	93
Restore the factory-set defaults ...................................................................	93
Restore the factory-set defaults (LCD control panel) .........................	94
Restore the factory-set defaults (touchscreen control panel) ..............	94
Secondary service menu ..........................................................................................	94
Open the secondary service menu (LCD control panel) ..................................	94
Open the secondary service menu (touchscreen control panel) .......................	94
Secondary service menu structure ...............................................................	95
Engine resets ..........................................................................................................	96
Engine test page ......................................................................................	96
Cold reset ...............................................................................................	96
NVRAM initialization ................................................................................	96

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Product updates .....................................................................................................................	97
Appendix A Service and support .......................................................................................	99
Hewlett-Packard limited warranty statement .............................................................................	100
HP's Premium Protection Warranty: LaserJet print cartridge limited warranty statement ..................	102
Data stored on the print cartridge ...........................................................................................	103
End User License Agreement ..................................................................................................	104
OpenSSL .............................................................................................................................	106
Customer support .................................................................................................................	107
Repack the product ..............................................................................................................	108
Appendix B Product specifications ...................................................................................	109
Physical specifications ..........................................................................................................	110
Power consumption, electrical specifications, and acoustic emissions ..........................................	110
Environmental specifications ..................................................................................................	110
Appendix C Regulatory information .................................................................................	111
FCC regulations ...................................................................................................................	112
Environmental product stewardship program ...........................................................................	113
Protecting the environment ......................................................................................	113
Ozone production .................................................................................................	113
Power consumption ...............................................................................................	113
Paper use .............................................................................................................	113
Plastics .................................................................................................................	113
HP LaserJet print supplies .......................................................................................	113
Return and recycling instructions .............................................................................	114
United States and Puerto Rico ..................................................................	114
Multiple returns (more than one cartridge) ..................................	114
Single returns ..........................................................................	114
Shipping ................................................................................	114
Non-U.S. returns ....................................................................................	115
Paper ..................................................................................................................	115
Material restrictions ...............................................................................................	115
Disposal of waste equipment by users in private households in the European Union ......	115
Chemical substances .............................................................................................	115
Material Safety Data Sheet (MSDS) .........................................................................	116
For more information .............................................................................................	117
Declaration of conformity ......................................................................................................	118
Declaration of conformity (wireless model) ..............................................................................	120
Certificate of Volatility ..........................................................................................................	122

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Safety statements .................................................................................................................	123
Laser safety ..........................................................................................................	123
Canadian DOC regulations ....................................................................................	123
VCCI statement (Japan) ..........................................................................................	123
Power cord instructions ..........................................................................................	123
Power cord statement (Japan) .................................................................................	123
EMC statement (Korea) ..........................................................................................	124
Laser statement for Finland .....................................................................................	125
GS statement (Germany) ........................................................................................	125
Substances Table (China) .......................................................................................	126
Restriction on Hazardous Substances statement (Turkey) .............................................	126
Additional statements for wireless products ..............................................................................	127
FCC compliance statement—United States ................................................................	127
Australia statement ................................................................................................	127
Brazil ANATEL statement ........................................................................................	127
Canadian statements .............................................................................................	127
European Union regulatory notice ...........................................................................	127
Notice for use in France .........................................................................................	128
Notice for use in Russia .........................................................................................	128
Korean statement ..................................................................................................	128
Taiwan statement ..................................................................................................	129
Index ...............................................................................................................................	131

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List of tables

Table 1-1 Sequence of operation ............................................................................................................	4
Table 2-1 DC controller connectors .......................................................................................................	32
Table 2-2 Major components ...............................................................................................................	34
Table 2-3 Repetitive image defects ........................................................................................................	41
Table 2-4 Event-log messages ...............................................................................................................	64
Table 2-5 Secondary Service menu .......................................................................................................	95
Table B-1 Physical specifications .........................................................................................................	110
Table B-2 Environmental specifications ................................................................................................	110

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List of figures

Figure 1-1 Product systems .....................................................................................................................	2
Figure 1-2 Product components ...............................................................................................................	3
Figure 1-3 Engine control system components ...........................................................................................	5
Figure 1-4 DC controller circuit diagram ..................................................................................................	6
Figure 1-5 Low-voltage power supply ......................................................................................................	7
Figure 1-6 High-voltage power supply .....................................................................................................	8
Figure 1-7 Laser/scanner system .............................................................................................................	9
Figure 1-8 Image-formation system ........................................................................................................	10
Figure 1-9 Image-formation process ......................................................................................................	11
Figure 1-10 Primary charging ...............................................................................................................	12
Figure 1-11 Laser-beam exposure .........................................................................................................	12
Figure 1-12 Development .....................................................................................................................	13
Figure 1-13 Primary transfer .................................................................................................................	14
Figure 1-14 Secondary transfer ............................................................................................................	14
Figure 1-15 Separation from the ITB ......................................................................................................	15
Figure 1-16 Fusing ..............................................................................................................................	15
Figure 1-17 ITB cleaning ......................................................................................................................	16
Figure 1-18 Drum cleaning ..................................................................................................................	17
Figure 1-19 Pickup-and-feed system .......................................................................................................	18
Figure 2-1 DC controller connectors ......................................................................................................	32
Figure 2-2 Major components ..............................................................................................................	34
Figure 2-3 Timing diagram ...................................................................................................................	36
Figure 2-4 Circuit diagram ...................................................................................................................	37

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1 Theory of operation

This chapter presents an overview of the major components of the printer and includes a detailed discussion of the image-formation system.

●Basic operation

●Engine control system

●Laser/scanner system

●Image-formation system

●Pickup-and-feed system

●USB flash drive

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1

Basic operation

Major product systems

The product includes the following systems:

●Engine control system

●Laser/scanner system

●Image-formation system

●Pickup-and-feed system

Figure 1-1 Product systems

ENGINE CONTROL

SYSTEM

LASER/SCANNER SYSTEM

IMAGE-FORMATION SYSTEM

PICKUP-AND-FEED SYSTEM

2

Chapter 1 Theory of operation

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Product components
Figure 1-2		Product components
1	2	3	4	5

14	13	12	11	10	9	8	7	6
Item			Description			Item		Description
1			Fuser unit			8		Cassette
2			Delivery roller			9		Pickup roller
3			ITB drive roller			10		Separation roller
4			Photosensitive drum			11		Registration roller
5			Laser scanner assembly			12		Secondary transfer roller
6			Transfer pad			13		Fusing film
7			Intermediate transfer belt (ITB)			14		Pressure roller

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Basic operation

3

Sequence of operation

Table 1-1 Sequence of operation

Period	Duration	Purpose	Remarks
WAIT	From the time the power is	Clears the potential from the	Detects the cartridge
	turned on or the door is	drum surface, adjusts the	presence and environment;
	closed, until the printer is	drum phase, and cleans the	completes any required
	ready for a print operation	ITB	calibration (color registration
			control and image stability)
STBY (Standby period)	From end of the WAIT or	Maintains the printer in	The printer enters sleep mode
	LSTR period until either the	readiness for a print	when the formatter sends a
	print command is received	command	sleep command, and
	from the formatter or the		performs color registration
	power is turned off		and the image stability
			control when the formatter
			sends those commands
INTR (Initial rotation)	From the time the print	Prepares the photosensitive
	command is received until the	drum for printing
	media is picked up
PRINT	From the end of INTR period	Forms the images on the	Performs image stabilization
	until the fuser paper sensor	photosensitive drum and	at a specified print interval or
	detects the trailing edge of	transfers the toner image to	at specified times
	paper	the print media
LSTR (Last rotation)	From the end of the PRINT	Moves the printed sheet out	The printer enters the INTR
	period until the delivery motor	of the printer	period as soon as the
	stops rotating		formatter sends another print
			command

4

Chapter 1 Theory of operation

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Engine control system

The engine control system coordinates all printer functions and drives the other three systems.

The engine control system contains the DC controller, high-voltage power-supply PCA, low-voltage power-supply unit, and fuser control.

Figure 1-3 Engine control system components

Engine-control system

Laser scanner system

DC controller

Low-voltage power supply

Formatter

Image-formation system

High-voltage power supply

Fuser control

Pickup, feed and delivery system

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Engine control system

5

DC controller

Figure 1-4 DC controller circuit diagram

Driver

Low-voltage power supply

AC input

Fuser power supply

Fuser

DC controller

High-voltage

power supply

T2 roller

Cartridge

NOTE: USB block for touchscreen-equipped models only.

Motor

Fan

Solenoid

Photointerrupter

Switch

ITB assembly

Laser scanner assembly

USB (NOTE)

Formatter

Control panel

6

Chapter 1 Theory of operation

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Low-voltage power supply

Figure 1-5 Low-voltage power supply

AC input

DC controller

Fuse

FU901

Fuser control circuit

Fuse

FU801

Fuser power supply

Rectifying

circuit

	PWSV	Power switch
		SW801

+24V	+24VR	+24V	REM24V
			+24VA
generation		control circuit
circuit
		+3.3V	+3.3VA	+3.3VA
		generation
		circuit	VCTRLOFF	+3.3VB
Protection		+3.3V
circuit		control circuit

+24VA Power switch

control circuit

Low-voltage power supply	+3.3VC	Formatter

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Engine control system

7

High-voltage power supply

Figure 1-6 High-voltage power supply

Primary charging bias circuit					Developing bias circuit

Cartridge

Photosensitive drum

T1 pad

ITB cleaning	ITB
ass’y
	T2 roller

ITB cleaning brush

ITB cleaning roller

T2 bias circui

T1 bias circuit

bias circuit

bias circuit

High-voltage power supply

DC controller

8

Chapter 1 Theory of operation

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Laser/scanner system

The formatter sends video signals to the DC controller, which controls the laser/scanner. When the laser/scanner system receives those signals, it converts them to latent images on the photosensitive drum.

Figure 1-7 Laser/scanner system

Laser assembly

Scanner mirror

Scanner motor assembly

BD sensor

Photosensitive drum

(Y)

Photosensitive drum

(M)

Photosensitive drum

(C)

Photosensitive drum

(K)

DC controller

Laser failure detection

The optical unit failure detection sensor manages the laser/scanner unit failure-detection functions. The DC controller identifies the laser/scanner unit failure and notifies the formatter if the laser/scanner unit encounters the following conditions:

●Scanner motor failure

●BD failure

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Laser/scanner system

9

Image-formation system

The image-formation system forms a toner image on media. The product includes four toner cartridges that contain the toner. Toner is applied in the following order, using only the colors necessary for a specific image: yellow (Y), magenta (M), cyan (C), and black (K).

Figure 1-8 Image-formation system

DC controller

High-voltage power supply

Fuser

Laser scanner assembly

Cartridge

Y

M

C

K

ITB

T1 pad	Photosensitive drum
T2 roller

Image-formation process

Laser printing requires the interaction of several different technologies including electronics, optics, and electrographics to provide a printed page. Each process functions independently and must be coordinated with the other processes. Image formation consists of the following processes:

●Latent-image formation

●Development

●Transfer

10 Chapter 1 Theory of operation

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●Fuser

●ITB cleaning

●Drum cleaning

These processes are divided into nine steps, which are shown in Figure 1-9 Image-formation process on page 11 and described in the following sections.

Figure 1-9	Image-formation process
			: Media path
			: Direction of drum rotation
	Delivery		: Block
			: Step
		Latent image formation
7. Fusing		2. Laser beam exposure
Fuser
		1. Primary charging
	3. Development
	Development	Photosensitive drum cleaning
	Transfer	9. Drum cleaning
6. Separation
		4. Primary transfer
5. Secondary transfer
		8. ITB cleaning
Registration		ITB cleaning

Pickup

Latent-image formation stage

During the two steps that comprise this stage, a latent image is formed by applying a negative charge to the photosensitive drum. You cannot see this image on the drum.

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Step 1: primary charging

A high-voltage DC bias is applied to the primary charging roller, which is made of conductive rubber and is in contact with the drum surface. As the roller moves across the drum, it applies the negative charge to that surface.

Figure 1-10 Primary charging

Primary charging roller

DC bias

Photosensitive drum

Step 2: laser-beam exposure

The laser beam scans the photosensitive drum to neutralize the negative charge on portions of the drum surface. An electrostatic latent image is formed where the negative charge was neutralized.

Figure 1-11 Laser-beam exposure

Laser beam

Unexposed area

Exposed area

Developing stage

The developer roller comes in contact with the photosensitive drum and deposits toner on the electrostatic latent image.

12 Chapter 1 Theory of operation

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Step 3: development

Toner acquires a negative charge as a result of the friction from the developer roller rotating against the developer blade. When the negatively charged toner comes in contact with the drum, it adheres to the electrostatic latent image. When the toner is on the drum, the image becomes visible.

Figure 1-12 Development

Developer blade

	Developer roller
	DC negative bias
Exposed area	Unexposed area
Unexposed area	Exposed area

Photosensitive drum

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Transfer stage

Step 4: primary transfer

The toner image on the photosensitive drum is transferred to the ITB. The DC positive bias is applied to the primary transfer pad. The negatively charged toner transfers to the ITB from the drum surface.

Figure 1-13 Primary transfer

Photosensitive

drum

ITB

T1 pad

T1 bias

Step 5: secondary transfer

The toner image on the ITB is transferred to the print media. The DC positive bias is applied to the secondary transfer roller. As the media passes between the secondary transfer roller and the ITB, the toner image is transferred to the media.

Figure 1-14 Secondary transfer

Media

ITB

ITB drive roller

Secondary transfer roller

DC bias

14 Chapter 1 Theory of operation

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Step 6: separation from the ITB

The elasticity of the print media and the curvature of the ITB drive roller cause the media to separate from the ITB.

Figure 1-15 Separation from the ITB

Media

ITB

ITB drive roller

Secondary transfer roller

Fusing stage

Until the fusing stage is complete, the image is not permanently affixed to the print media. The toner can be easily smudged until the heat and pressure of the fusing process fix the image to the sheet.

Step 7: fusing

The product uses an on-demand fixing method to fix the toner image onto the media. The toner image is permanently affixed to the print media by heat and pressure.

Figure 1-16 Fusing

Fuser film

Fuser heater

Toner

Paper

Pressure roller

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ITB cleaning stage

Step 8: ITB cleaning

The ITB cleaning roller and the cleaning brush are applied with the DC positive bias to charge the residual toner positive. Because the primary transfer pad is also applied with the DC positive bias, the positively charged residual toner is reverse-transferred to the photosensitive drum from the ITB surface.

Figure 1-17 ITB cleaning

Positive potential waste toner

Cartridge

Negative potential waste toner

Partition sheet

ITB cleaning brush

Sweeper strip

Photosensitive drum ITB cleaning roller

IT B

DC bias

DC bias

16 Chapter 1 Theory of operation

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Drum cleaning stage

Not all of the toner is removed from the photosensitive drum during the transfer stage. During the cleaning stage, the residual, or waste, toner is cleared from the drum surface to prepare the surface for the next latent-image formation.

Step 9: drum cleaning

The cleaning blade scrapes the residual toner off the surface of the photosensitive drum and deposits it in the waste-toner container. The drum is now clear and is ready for the next image-formation process.

Figure 1-18 Drum cleaning

Cleaning blade

Blowout seal

Photosensitive

drum

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