HP LaserJet Pro MFP M225, LaserJet Pro MFP M226, LaserJet Pro M201, LaserJet ProM202 Troubleshooting Manual
Troubleshooting Manual
LaserJet Pro M201, M202
M201dw
M202dw
M201n
M202n
www.hp.com/support/ljM201
www.hp.com/support/ljM202
www.hp.com/support/ljMFPM225
www.hp.com/support/ljMFPM226
M225dn
M225rdn
M226dn
M225dw
M226dw
LaserJet Pro MFP M225, M226
HP LaserJet Pro MFP M225/M226 and HP
LaserJet Pro M201/M202 Printer series
Troubleshooting Manual
Copyright and License
Trademark Credits
© 2014 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.
Edition 1, 10/2014
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.
ENWW iii
Table of contents
1 Theory of operation ....................................................................................................................................... 1
Basic operation ...................................................................................................................................................... 2
Major product systems ........................................................................................................................ 2
Product block diagram ........................................................................................................................ 2
Sequence of operation ........................................................................................................................ 3
Normal sequence of operation ......................................................................................... 3
Formatter-control system ..................................................................................................................................... 4
Sleep mode .......................................................................................................................................... 4
Input/output ........................................................................................................................................ 4
CPU ....................................................................................................................................................... 4
Memory ................................................................................................................................................ 4
Firmware ........................................................................................................................... 4
Memory use ....................................................................................................................... 5
PJL overview ........................................................................................................................................ 5
PML ...................................................................................................................................................... 5
LEDM overview .................................................................................................................................... 5
ACL overview ....................................................................................................................................... 6
Control panel ....................................................................................................................................... 6
USB flash drive .................................................................................................................................... 6
Engine-control system .......................................................................................................................................... 7
DC controller operations ..................................................................................................................... 8
Motors, fans, clutches, solenoids, switches, and sensors ............................................................... 10
Fuser-control circuit .......................................................................................................................... 14
Fuser failure detection ................................................................................................... 15
Fuser temperature control ............................................................................................. 16
Fuser heater protective function .................................................................................... 17
Pressure roller cleaning .................................................................................................. 17
Low-voltage power supply ............................................................................................................... 18
Overcurrent/overvoltage protection .............................................................................. 20
High-voltage power supply ............................................................................................................... 21
Laser/scanner system ......................................................................................................................................... 22
Laser failure detection ...................................................................................................................... 22
ENWW v
Image-formation system .................................................................................................................................... 24
Electrophotographic process ............................................................................................................ 24
Image formation process .................................................................................................................. 26
Latent-image formation stage ....................................................................................... 27
Primary charging .......................................................................................... 27
Laser beam exposure ................................................................................... 27
Developing stage ............................................................................................................ 28
Print cartridge ............................................................................................... 28
Transfer stage ................................................................................................................. 29
Fusing stage ................................................................................................. 29
Cleaning stage .............................................................................................. 30
Pickup, feed, and delivery system ...................................................................................................................... 31
Photo sensors and switches ............................................................................................................. 32
Multiple-feed prevention .................................................................................................................. 34
Jam detection .................................................................................................................................... 34
Scanning and image capture system .................................................................................................................. 36
Scanner power-on sequence of events ............................................................................................ 36
Copy or scan sequence of events ...................................................................................................... 37
Scanner operation ............................................................................................................................. 38
ADF operation ...................................................................................................................................................... 39
ADF paper path and ADF sensors ...................................................................................................... 39
ADF jam detection ............................................................................................................................. 40
Fax functions and operation ............................................................................................................................... 42
Computer and network security features ........................................................................................ 42
PSTN operation ................................................................................................................................. 42
Receive faxes when you hear fax tones ........................................................................................... 42
Distinctive ring function .................................................................................................................... 43
Fax by using Voice over IP services ................................................................................................... 43
The fax subsystem ............................................................................................................................ 44
Fax card in the fax subsystem .......................................................................................................... 44
Safety isolation ............................................................................................................... 44
Safety-protection circuitry ............................................................................................. 44
Data path ......................................................................................................................... 44
Hook state ....................................................................................................................... 45
Downstream current detection ...................................................................................... 45
Hook switch control ........................................................................................................ 45
Ring detect ...................................................................................................................... 45
Line current control ........................................................................................................ 45
Billing- (metering-) tone filters ...................................................................................... 46
Fax page storage in flash memory ................................................................................................... 46
Stored fax pages ............................................................................................................. 46
vi ENWW
Advantages of flash memory storage ............................................................................ 46
USB flash drive ..................................................................................................................................................... 47
2 Solve problems ........................................................................................................................................... 49
Troubleshooting process .................................................................................................................................... 50
Pre-troubleshooting checklist .......................................................................................................... 50
Determine the problem source ......................................................................................................... 51
Troubleshooting flowchart ............................................................................................. 51
Power subsystem .............................................................................................................................. 52
Power-on checks ............................................................................................................ 52
Control-panel checks ........................................................................................................................ 52
Tools for troubleshooting ................................................................................................................................... 54
Individual component diagnostics .................................................................................................... 54
Engine diagnostics .......................................................................................................... 54
Engine-test button ....................................................................................... 54
Components tests ........................................................................................................... 55
Drum rotation functional check .................................................................. 55
Half self-test functional check ..................................................................... 55
Diagrams ........................................................................................................................................... 55
Location of connectors ................................................................................................... 56
Plug/jack locations ......................................................................................................... 58
Locations of major components ..................................................................................... 60
General timing charts ..................................................................................................... 65
General circuit diagrams ................................................................................................. 66
Advanced configuration with HP Embedded Web Server (EWS) and HP Device Toolbox
(Windows) .......................................................................................................................................... 67
Internal print-quality test pages ...................................................................................................... 70
Cleaning page .................................................................................................................. 70
Configuration page ......................................................................................................... 70
Print-quality troubleshooting tools ................................................................................................. 71
Repetitive defect ruler .................................................................................................... 71
Control panel menus ......................................................................................................................... 71
Print product reports and menu maps ........................................................................... 71
Tools for troubleshooting: Control panel menus .......................................................... 71
Setup menu .................................................................................................. 71
Function-specific menus (MFP products only) ............................................ 83
Interpret control panel messages .................................................................................................... 89
Control panel message types ......................................................................................... 89
Control panel messages ................................................................................................. 89
Event-log messages .......................................................................................................................... 99
Print the event log .......................................................................................................... 99
ENWW vii
Show an event log ........................................................................................................... 99
Event log messages ........................................................................................................ 99
Improve print quality, print-only products ....................................................................................................... 102
Improve print quality ...................................................................................................................... 102
Print from a different software program ..................................................................... 102
Check the paper-type setting for the print job ............................................................ 102
Check the paper type setting (Windows) ................................................... 102
Check the paper type setting (OS X) .......................................................... 102
Check the toner-cartridge status ................................................................................. 103
Print a cleaning page .................................................................................................... 103
Visually inspect the toner cartridge for damage ......................................................... 104
Check paper and the printing environment ................................................................. 104
Step one: Use paper that meets HP specifications .................................... 104
Step two: Check the environment .............................................................. 104
Check other print job settings ...................................................................................... 105
Check the EconoMode settings .................................................................. 105
Try a different print driver ............................................................................................ 106
Improve print quality, MFP products ................................................................................................................ 107
Improve print quality ...................................................................................................................... 107
Print from a different software program ..................................................................... 107
Set the paper-type setting for the print job ................................................................ 107
Check the paper-type setting (Windows) .................................................. 107
Check the paper type setting (OS X) .......................................................... 108
Check the toner-cartridge status ................................................................................. 108
Clean the product ......................................................................................................... 108
Print a cleaning page .................................................................................. 108
Check the scanner glass for dirt and smudges .......................................... 109
Inspect the toner cartridge for damage ....................................................................... 109
Check the paper and printing environment ................................................................. 110
Use paper that meets HP specifications .................................................... 110
Check the product environment ................................................................ 110
Check other print job settings ...................................................................................... 110
Check the EconoMode settings .................................................................. 110
Try a different print driver ............................................................................................ 112
Improve copy and scan quality ......................................................................................................................... 113
Check the scanner glass for dirt and smudges ............................................................................... 113
Check the paper settings ................................................................................................................ 113
Optimize for text or pictures .......................................................................................................... 113
Edge-to-edge copying .................................................................................................................... 114
Clean the pickup rollers and separation pad in the document feeder ........................................... 115
Improve fax image quality ................................................................................................................................ 116
viii ENWW
Check the scanner glass for dirt or smudges ................................................................................. 116
Check the send-fax resolution setting ........................................................................................... 116
Check the lightness/darkness setting ............................................................................................ 116
Check the Error Correction setting ................................................................................................. 117
Check the Fit-to-Page setting ......................................................................................................... 118
Clean the pickup rollers and separation pad in the document feeder ........................................... 118
Send to a different fax machine ..................................................................................................... 119
Check the sender's fax machine ..................................................................................................... 119
Solve Paper Jam or feed problems ................................................................................................................... 120
Product does not pick up paper or misfeeds .................................................................................. 120
The product does not pick up paper ............................................................................. 120
The product picks up multiple sheets of paper ........................................................... 120
The document feeder jams, skews, or picks up multiple sheets of paper .................. 120
Clean the pickup rollers and separation pad in the document feeder ........................ 121
Clear jams (print-only products) ..................................................................................................... 123
Jam locations ................................................................................................................ 123
Experiencing frequent or recurring paper jams? ......................................................... 123
Clear jams in the toner-cartridge area ......................................................................... 124
Clear jams in the output bin ......................................................................................... 125
Clear jams in the duplexer (dw models only) ............................................................... 127
Clear jams (MFP products) .............................................................................................................. 129
Jam locations ................................................................................................................ 129
Experiencing frequent or recurring paper jams? ......................................................... 129
Clear jams in the document feeder .............................................................................. 130
Clear jams in the toner-cartridge area ......................................................................... 124
Clear jams in the output bin ......................................................................................... 125
Clear jams in the duplexer ............................................................................................ 127
Solve performance problems ............................................................................................................................ 139
Factors affecting print performance .............................................................................................. 139
Print speeds .................................................................................................................. 139
The product does not print or it prints slowly ................................................................................ 140
The product does not print ........................................................................................... 140
The product prints slowly ............................................................................................. 141
Solve connectivity problems ............................................................................................................................. 142
Solve direct-connect problems ...................................................................................................... 142
Solve wired network problems ....................................................................................................... 142
Poor physical connection ............................................................................................. 142
The computer is using the incorrect IP address for the product ................................. 142
The computer is unable to communicate with the product ........................................ 143
The product is using incorrect link and duplex settings for the network ................... 143
New software programs might be causing compatibility problems ........................... 143
ENWW ix
The computer or workstation might be set up incorrectly .......................................... 143
The product is disabled, or other network settings are incorrect ............................... 143
Solve wireless network problems .................................................................................................. 143
Wireless connectivity checklist .................................................................................... 144
The product does not print after the wireless configuration completes .................... 144
The product does not print, and the computer has a third-party firewall installed ... 145
The wireless connection does not work after moving the wireless router or
product .......................................................................................................................... 145
Cannot connect more computers to the wireless product .......................................... 145
The wireless product loses communication when connected to a VPN ...................... 145
The network does not appear in the wireless networks list ....................................... 145
The wireless network is not functioning ...................................................................... 145
Perform a wireless network diagnostic test ................................................................ 146
Reduce interference on a wireless network ................................................................ 146
Service mode functions, print-only products ................................................................................................... 147
Restore the factory-set defaults .................................................................................................... 147
Service mode functions, MFP products ............................................................................................................. 148
Restore the factory-set defaults .................................................................................................... 148
Solve fax problems ............................................................................................................................................ 149
Check the hardware setup .............................................................................................................. 149
Faxes are sending slowly ................................................................................................................ 150
Fax quality is poor ........................................................................................................................... 151
Fax cuts off or prints on two pages ................................................................................................ 151
Product updates ................................................................................................................................................ 151
Update the firmware ....................................................................................................................... 151
Method one: Update the firmware using the control panel ........................................ 152
Method two: Update the firmware using the Firmware Update Utility ....................... 152
Appendix A Specifications ............................................................................................................................. 155
Physical specifications ...................................................................................................................................... 156
Power consumption .......................................................................................................................................... 156
Acoustic specifications ...................................................................................................................................... 156
Environmental specifications ............................................................................................................................ 157
Certificate of Volatility ...................................................................................................................................... 158
Index ........................................................................................................................................................... 161
x ENWW
List of tables
Table 1-1 Sequence of operation ......................................................................................................................................... 3
Table 1-2 DC controller controlled components .................................................................................................................. 8
Table 1-3 Motors ................................................................................................................................................................ 10
Table 1-4 Fans .................................................................................................................................................................... 11
Table 1-5 Solenoids and clutches ...................................................................................................................................... 12
Table 1-6 Switches ............................................................................................................................................................. 13
Table 1-7 Sensors ............................................................................................................................................................... 13
Table 1-8 List of DC power supply ...................................................................................................................................... 19
Table 1-9 Photo sensors, motor, and solenoid .................................................................................................................. 32
Table 2-1 Troubleshooting flowchart ................................................................................................................................ 51
Table 2-2 HP Web Services menu ....................................................................................................................................... 72
Table 2-3 Reports menu ..................................................................................................................................................... 72
Table 2-4 Self Diagnostics menu ....................................................................................................................................... 73
Table 2-5 Fax Setup menu .................................................................................................................................................. 73
Table 2-6 System Setup menu ........................................................................................................................................... 76
Table 2-7 Service menu ...................................................................................................................................................... 80
Table 2-8 Network Setup menu ......................................................................................................................................... 82
Table 2-9 Quick Forms Menu .............................................................................................................................................. 83
Table 2-10 Fax Menu .......................................................................................................................................................... 84
Table 2-11 Copy Menu ........................................................................................................................................................ 85
Table 2-12 Event-log messages ........................................................................................................................................ 99
Table 2-13 Event-log-only messages ............................................................................................................................. 100
Table 2-14 Factors affecting print performance ............................................................................................................. 139
Table A-1 Physical specifications1 ................................................................................................................................... 156
Table A-2 HP LaserJet Pro MFP M225/M226 and HP LaserJet Pro M201/M202 Printer series (average in watts)1 2 3 .. 156
Table A-3 HP LaserJet Pro MFP M225/M226 and HP LaserJet Pro M201/M202 Printer series1 ..................................... 156
Table A-4 Environmental specifications .......................................................................................................................... 157
ENWW xi
List of figures
Figure 1-1 Product block diagram ........................................................................................................................................ 2
Figure 1-2 Engine-control system ........................................................................................................................................ 7
Figure 1-3 DC controller block diagram ............................................................................................................................... 8
Figure 1-4 Motors ............................................................................................................................................................... 10
Figure 1-5 Fans ................................................................................................................................................................... 11
Figure 1-6 Solenoids and clutches ..................................................................................................................................... 12
Figure 1-7 Switches ............................................................................................................................................................ 13
Figure 1-8 Sensors .............................................................................................................................................................. 13
Figure 1-9 Fuser control circuit .......................................................................................................................................... 14
Figure 1-10 Fuser-heater control circuit ............................................................................................................................ 16
Figure 1-11 Low-voltage power supply (LVPS) ................................................................................................................. 18
Figure 1-12 High-voltage power supply ............................................................................................................................ 21
Figure 1-13 Laser/scanner system .................................................................................................................................... 22
Figure 1-14 Electrophotographic process block diagram (1 of 2) ..................................................................................... 24
Figure 1-15 Electrophotographic process block diagram (2 of 2) ..................................................................................... 25
Figure 1-16 Image formation process ............................................................................................................................... 26
Figure 1-17 Primary charging ............................................................................................................................................ 27
Figure 1-18 Laser beam exposure ..................................................................................................................................... 27
Figure 1-19 Print cartridge ................................................................................................................................................. 28
Figure 1-20 Transfer ........................................................................................................................................................... 29
Figure 1-21 Separation ....................................................................................................................................................... 29
Figure 1-22 Fusing .............................................................................................................................................................. 30
Figure 1-23 Drum cleaning ................................................................................................................................................. 30
Figure 1-24 Pickup, feed, and delivery system block diagram ......................................................................................... 31
Figure 1-25 Photo sensors, motor, and solenoid .............................................................................................................. 32
Figure 1-26 Multiple-feed prevention ................................................................................................................................ 34
Figure 1-27 Scanner mechanism ........................................................................................................................................ 38
Figure 1-28 ADF paper path ............................................................................................................................................... 40
Figure 2-1 Control-panel 2ndary Service test access buttons .......................................................................................... 53
Figure 2-2 Sample engine test page .................................................................................................................................. 54
Figure 2-3 Engine controller PCA connectors (M201, M202) ............................................................................................. 56
Figure 2-4 Engine controller PCA connectors (M225, M226) ............................................................................................. 57
ENWW xiii
Figure 2-5 Plug/jack locations (print-only products) ........................................................................................................ 58
Figure 2-6 Plug/jack locations (MFP products) .................................................................................................................. 59
Figure 2-7 Main assemblies ................................................................................................................................................ 60
Figure 2-8 Rollers, solenoids, and fan ............................................................................................................................... 61
Figure 2-9 PCA locations ..................................................................................................................................................... 62
Figure 2-10 Cross section view (M201, M202) ................................................................................................................... 63
Figure 2-11 Cross section view (M225, M226) ................................................................................................................... 64
Figure 2-12 General timing diagram .................................................................................................................................. 65
Figure 2-13 Circuit diagram (M201, M202) ........................................................................................................................ 66
Figure 2-14 Circuit diagram (M225, M226) ........................................................................................................................ 67
Figure A-1 Certificate of Volatility (1 of 2) ....................................................................................................................... 158
Figure A-2 Certificate of Volatility (2 of 2) ....................................................................................................................... 159
xiv ENWW
1 Theory of operation
●
Basic operation
●
Formatter-control system
●
Engine-control system
●
Laser/scanner system
●
Image-formation system
●
Pickup, feed, and delivery system
●
Scanning and image capture system
●
ADF operation
●
Fax functions and operation
●
USB flash drive
ENWW 1
Basic operation
PICKUP-AND-FEED SYSTEM
LASER/SCANNER SYSTEM
ENGINE CONTROL
SYSTEM
IMAGE-FORMATION SYSTEM
Major product systems
The product contains the following major systems:
●
Engine-control system
●
Laser/scanner system
●
Image-formation system
●
Pickup-and-feed system
Product block diagram
Figure 1-1 Product block diagram
2 Chapter 1 Theory of operation ENWW
Sequence of operation
The DC controller in the engine-control system controls the operational sequences of the product. The table
below describes durations and operations for each period of a print operation from when the product is
turned on until the motor stops rotating.
Normal sequence of operation
Table 1-1 Sequence of operation
Name Timing Purpose
WAIT From the time the power switch is turned on, the door is
closed or the product exits Sleep mode until the product
gets ready for a print operation.
STBY (standby) From the end of the WAIT or LSTR period until either a
print command is sent or the power switch is turned off.
INTR (initial
rotation)
PRINT From the end of the INTR period until the last sheet
LSTR (last
rotation)
From the time a print command is received until the
paper is picked up.
completes the fuser operation.
From the end of the PRINT period until the main motor
stops rotating.
Brings the product to ready state. The product
performs the following during the operations:
●
Detects the print cartridge
●
Heats the fuser film in the fuser
●
Rotates, and the stops, the main motor
Maintains the product in printable condition. The
product performs the following during the operation:
●
Enters Auto-Off mode if Auto-Off command is
received
The product performs the following during the
operations:
●
Drives the main motor
●
Activates the high-voltage power supply
●
Activates the laser/scanner
●
Warms the fuser heater
Forms the image on the photosensitive drum based on
the VIDEO signals from the formatter. Transfers and
fuses the toner image to the paper.
Moves the last printed sheet out of the product. The
product performs the following during the operations:
●
Stops the main motor
●
Deactivates the high-voltage power supply
●
Deactivates the laser/scanner
●
Deactivates the fuser heater
The product enters the INTR period as the LSTR period
is completed, if the formatter sends another print
command.
ENWW Basic operation 3
Formatter-control system
The formatter is responsible for the following procedures:
●
Controlling sleep mode
●
Receiving and processing print data from the various product interfaces
●
Monitoring control-panel functions and relaying product-status information (through the control panel
and the network or bidirectional interface)
●
Developing and coordinating data placement and timing with the DC controller PCA
●
Storing font information
●
Communicating with the host computer through the network or the bidirectional interface
The formatter receives a print job from the network or bidirectional interface and separates it into image
information and instructions that control the printing process. The DC controller PCA synchronizes the imageformation system with the paper-input and -output systems, and then signals the formatter to send the
print-image data.
Sleep mode
NOTE: This product uses an Auto-Off feature for sleep mode.
After a user-specified time, the Auto-Off feature automatically conserves electricity by substantially
reducing power consumption when the product is not printing. After a user-specified time, the product
automatically reduces its power consumption (Auto-Off). The product returns to the ready state when a
button is pressed, a print job is received, or a door is opened. When the product is in Auto-Off mode, all of the
control-panel LEDs and the power button backlight LED are off.
NOTE: Although the product lights are off in Auto-Off mode, the product functions normally when it
receives a print job.
Input/output
The product receives print data primarily from the following:
●
Hi-Speed USB 2.0 port
●
802.11b/g/n wireless networking (wireless models only)
CPU
The formatter incorporates a 750 MHz ARM processor.
Memory
The random access memory (RAM) on the formatter PCA contains the page, I/O buffers, and the font storage
area. RAM stores printing and font information received from the host system, and can also serve to
temporarily store a full page of print-image data before the data is sent to the print engine.
Firmware
●
HP LaserJet Pro MFP M225/M226 Printer series
4 Chapter 1 Theory of operation ENWW
◦
●
HP LaserJet Pro M201/M202 Printer series
◦
Memory use
●
HP LaserJet Pro MFP M225/M226 Printer series
◦
●
HP LaserJet Pro M201/M202 Printer series
◦
PJL overview
The printer job language (PJL) is an integral part of configuration, in addition to the standard printer
command language (PCL). With standard cabling, the product can use PJL to perform a variety of functions
such as these:
The product has 256 MB of Synchronous DRAM, which is used for run-time firmware imaging and
specific print job information for the print job.
The product has 128 MB of Synchronous DRAM, which is used for run-time firmware imaging and
specific print job information for the print job.
The product has a 2 KB EEPROM and 256 MB of NAND Flash Memory, which is used for product
configuration information and printer driver firmware.
The product has a 8 KB EEPROM and 64 MB of NAND Flash Memory, which is used for product
configuration information and printer driver firmware.
●
Two-way communication with the host computer through a network connection or a USB connection.
The product can inform the host about such things as the control-panel settings, and the control-panel
settings can be changed from the host.
●
Dynamic I/O switching. The product uses this switching to be configured with a host on each I/O. The
product can receive data from more than one I/O simultaneously, until the I/O buffer is full. This can
occur even when the product is offline.
●
Context-sensitive switching. The product can automatically recognize the personality (PS or PCL) of
each job and configure itself to serve that personality.
●
Isolation of print environment settings from one print job to the next. For example, if a print job is sent
to the product in landscape mode, the subsequent print jobs print in landscape mode only if they are
formatted for landscape printing.
PML
The printer management language (PML) allows remote configuration and status monitoring through the I/O
ports.
LEDM overview
NOTE: HP LaserJet Pro M201/M202 Printer series
The low-end data model (LEDM) provides one consistent data representation method and defines the
dynamic and capabilities tickets shared between clients and devices, as well as the access protocol, event,
security, and discovery methods.
ENWW Formatter-control system 5
ACL overview
The advanced control language (ACL) is a language that supports product control and firmware downloads in
printers that support both PJL/PCL and host-based printing. Each sequence of ACL commands must be
preceded by a unified exit command (UEL) and an @PJL ENTER LANGUAGE=ACL command. The ACL sequence
is always followed by a UEL. Any number of commands can be placed between the UELs. The only exception
to these rules is the download command. If a firmware download is done, the download command must be
the last command in the sequence. It will not be followed by a UEL.
The firmware searches for the UEL sequence when parsing commands. However, while downloading binary
data such as host-based code or NVRAM data the firmware suspends UEL parsing. To handle hosts that
“disappear” during binary sequences, the firmware times out all ACL command sessions. If a timeout occurs
during a non-download command sequence, it is treated as the receipt of a UEL. If a timeout occurs during
firmware download the product resets.
Control panel
The formatter sends and receives product status and command data to and from the control-panel PCA.
USB flash drive
This product features printing from a USB flash drive. This product supports printing the following types of
files from the USB flash drive.
●
PDF
●
RGB JPEG
When a USB flash drive is inserted into the front of the product, the control panel will display the USB Flash
Drive menu. The files present on the USB flash drive can be accessed from the control panel using the touch
screen. Any RGB jpeg or pdf files on the USB flash drive can be printed directly from the product control
panel. Pages also can be scanned and saved to the USB flash drive from the control panel.
6 Chapter 1 Theory of operation ENWW
Engine-control system
Formatter
Engine-control system
DC controller
Low-voltage power supply
Laser scanner system
Image-formation system
Pickup, feed and delivery
system
High-voltage power supply
Fuser control
Engine controller
The engine-control system coordinates all product functions, according to commands that the formatter
sends. The engine-control system drives the laser/scanner system, the image-formation system, and the
pickup/feed/delivery system.
The engine control system contains the following major components:
●
Engine-control unit (ECU)
◦
DC controller
◦
Low-voltage power supply
●
High-voltage power supply
●
Fuser control
Figure 1-2 Engine-control system
ENWW Engine-control system 7
DC controller operations
Fuser
Transfer roller
Cartridge
Control panel
High-voltage
power supply
DC controller
Engine controller
Low-voltage
power supply
Motor
Fan
Solenoid
Photointerrupter
Switch
Laser scanner ass’y
Formatter
AC input
The DC controller controls the operational sequences of the product systems.
Figure 1-3 DC controller block diagram
Table 1-2 DC controller controlled components
Component Designator Description
Motor M1 Main motor
M2 Scanner motor
Fan FM1 Main fan
Solenoid SL1 Pickup solenoid
Switch SW501 Cartridge-door switch
Photointerrupter PS701 Fuser delivery sensor
SL2 Duplex reverse solenoid
PS702 Media-width sensor
Duplex models only.
NOTE: Duplex models only.
8 Chapter 1 Theory of operation ENWW
Table 1-2 DC controller controlled components (continued)
Component Designator Description
PS751 Top-of-Page (TOP) sensor
PS901 Main-motor rotation-number detection sensor
ENWW Engine-control system 9
Motors, fans, clutches, solenoids, switches, and sensors
M1
M2
Figure 1-4 Motors
Table 1-3 Motors
Item Description Components driven
M1 Main motor
M2 Scanner motor
●
Pickup roller
●
Feed roller
●
Photosensitive drum
●
Developing roller
●
Pressure roller
●
Delivery roller
●
Duplex feed roller
●
Scanner mirror
10 Chapter 1 Theory of operation ENWW
Figure 1-5 Fans
FM1
Table 1-4 Fans
Item Description
FM1 Main fan
ENWW Engine-control system 11
Figure 1-6 Solenoids and clutches
SL1
SL2
Table 1-5 Solenoids and clutches
Item Description
SL1 Pickup solenoid
SL2 Duplex reverse solenoid
NOTE: Duplex models only.
12 Chapter 1 Theory of operation ENWW
Figure 1-7 Switches
PS751
PS701
PS702
Table 1-6 Switches
Item Description
SW501 Cartridge-door switch
SW502 Power switch; not shown
Figure 1-8 Sensors
Table
1-7 Sensors
Item Description
PS701 Fuser delivery sensor
ENWW Engine-control system 13
Table 1-7 Sensors (continued)
Fuser heater safety
circuit
H1
FU1
TH1
Fuser film
Pressure roller
FUSER TEMPERATURE signal
Fuser control
FUSER HEATER CONTROL signal
DC controller
Engine controller
Fuser heater control
circuit
Item Description
PS702 Media-width sensor
PS751 Top-of-Page (TOP) sensor
PS901 Main-motor rotation-number sensor; not shown
Fuser-control circuit
The fuser-control circuit monitors and controls the temperature in the fuser. The product uses on-demand
fusing. The fuser-control circuit consists of the following major components:
●
Fuser heater (H1); heats the center area of the fusing film
●
Thermal fuse (FU1): Prevents an abnormal temperature rise of fuser heater (Contact type)
●
Thermistor (TH1); detects the center temperature of the fuser heater (contact type)
Figure 1-9 Fuser control circuit
14 Chapter 1 Theory of operation ENWW
Fuser failure detection
The DC controller determines a fuser unit failure, releases the relay to interrupt power supply to the fuser
heater, and notifies the formatter of a failure state when it encounters the following conditions:
●
Start up failure
◦
If the main thermistor does not detect a specified temperature during the start up process of the
heater in the wait period.
◦
If the main thermistor does not detect a specified temperature during the heater temperature
control in the initial rotation period.
●
Abnormal low temperature
◦
If the main thermistor detects an abnormal low temperature of the fuser unit during the printing
operation.
●
Abnormal high temperature
◦
If the main thermistor detects an abnormal high temperature of the fuser unit.
●
Frequency detection circuit failure
◦
If a specified frequency of the FREQUENCY signal is not detected within a specified period after the
product is turned on.
ENWW Engine-control system 15
Fuser temperature control
AC power supply
Engine controller
DC controller
Fuser control
Fuser
Pressure roller
Fuser film ass’y
FREQSNS
FSRTH
FSRD
Frequency detection
circuit
(220-240V only)
Fuser heater
control circuit
Fuser heater
safety circuit
Relay control
circuit
RL101
H1
FU1
TH1
RLYD
The fuser temperature control maintains the temperature of the fuser heater at its targeted temperature.
The DC controller monitors the FIXING TEMPERATURE (FSRTH) signals and sends the FIXING HEATER CONTROL
(FSRD) signal according to the detected temperature. The fuser heater control circuit controls the fuser
heater depending on the signal so that the heater remains at the targeted temperature.
Figure 1-10 Fuser-heater control circuit
16 Chapter 1 Theory of operation ENWW
Fuser heater protective function
The fuser heater protective function detects an excessive temperature rise of the fuser unit and interrupts
power supply to the fuser heater.
The following three protective components prevent an abnormal temperature rise of the fuser heater:
●
DC controller
◦
The DC controller monitors the detected temperature of the thermistor. The DC controller
deactivates the FUSER HEATER CONTROL signal and releases the relay (RL101) to interrupt power
supply to the fuser heater when it detects an excessive temperature.
●
Fuser heater safety circuit
◦
The fuser heater safety circuit monitors the detected temperature of the thermistor. The fuser
heater safety circuit releases the relay (RL101) to interrupt power supply to the fuser heater when
it detects an excessive temperature.
●
Thermal fuse
◦
The thermal fuse blows to interrupt power supply to the fuser heater when the temperature of the
fuser heater is abnormally high.
Pressure roller cleaning
The pressure roller cleaning process is initiated by the formatter. The process removes toner that has
accumulated on the pressure roller by transferring it to a sheet of paper.
●
The product feeds a sheet of paper after receiving the cleaning command from the formatter.
●
Main motor rotation is stopped when the trailing edge of the paper passes through the transfer roller.
●
The main motor rotation is repeatedly started and then stopped. The fuser heater is turned on and then
off at the same interval as main motor rotation.
●
Toner adhered to the pressure roller is fused to the paper.
●
The paper is ejected from the product.
ENWW Engine-control system 17
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