Page
 Warranty
 Conventions
T e
Page
 Contents
Page
 Preventive Maintenance
 Functional Overview
 Removal and Replacement
 Troubleshooting
 Parts and Diagrams
Duplexer
 LaserJet 5/5M/5N Printer
Page
 Contents-10
 Printer Features
Product Information
 Product Family Information
Product Family Compatibility Matrix
 Identification
CodeMeaning
 Printer Identification Label for the HP LaserJet 4/4M
 Specifications
Printer Dimensions
Power Specifications
HP LaserJet 4 and 4 Plus
 Electrical Specifications
Environmental Specifications
 Related Documentation
Printer Documentation
HP LaserJet 4 Documents-Description Part Number
HP LaserJet 4 Plus Documents-Description Part Number
 U t i o n
Safety Information
Product and Laser Safety
 FCC RFI Statement
 Laser Statement Sweden/Finland
Laserturvallisuus Luokan 1 Laserlaite
 Toner Safety
Ozone Statement
 HP FIRST, Europe
Doing Business with HP
Technical Assistance HP Asap 1-800-333-1917 U.S
 HP CompuServe Forum
Customer Information Centers
Customer Support Center Assist Line
Printer Drivers
 European Customer Support Center
Other Areas
 Site Planning Requirements
Site Requirements
 Printer Space Requirements
Space Requirements
 Media Specifications for PC Tray Tray
Print Media Specifications
Media Specifications for MP Tray Tray
 LaserJet 4 Plus, 4M Plus, 5, 5M, and 5N printers
Media Specifications for Optional LC Tray Tray
Media Specifications for Duplex Assembly HP
 Adhesive Labels
Label Construction
 Overhead Transparencies
Envelopes
 Specifications for Envelopes
Specifications
Dimensions
Envelope Construction
 Site Planning and Requirements
 Configuration
Introduction
 Control Panel Keys
Using The Control Panel
See Appendix B for LaserJet 5 information
 Indicator Lights
Indicator Mode Description
 Control Panel Key Functions
Key Function
 Reset Menu
Reset Menu Functions
 Control Panel Menus
 Control Panel Map
 Printer Menu Items
Options Explanation
 PCL Menu Items
Job Menu Items
 Configuration Menu Items
 Memory Configuration Items
Parallel Menu Items
 Serial Menu Items
Test Menu Items
 Printer Features
Protection HP LaserJet 4 only
 Resource Saving HP LaserJet 4 Plus and 5 only
 Buffering HP LaserJet 4 Plus and 5 only
 Resolution Enhancement REt
EconoMode HP LaserJet 4 Plus and 5 only
 Density
 Remote Control Panel DOS
Select Use Password from the Printer Passwords box
Network Security
HP LaserJet Utility Macintosh
 HP JetAdmin Utility Novell Networks
EC %-12345X@PJL JOB PASSWORD=numeric password
Select Lock Printer Control Panel
Ascii PJL Escape Sequence
 Service Mode
Refer to Appendix B for LaserJet 5 information
 Setting the Page Count
 Setting the Cold Reset Default
 Cold Reset
 Understanding the PCL Self Test Printout
Self Test Printout Items for the HP LaserJet 4/4M
 HP LaserJet 4/4M PCL Self Test Printout
 Self Test Printout Items HP LaserJet 4 Plus/4M
Plus
 HP LaserJet 4 Plus/4M Plus PCL Self Test Printout
 Changing the Control Panel Display Language
 Test Print Button
Test Print Button Location
 Test Print Pattern
 Parallel DOS Commands
System Configuration
MS-DOS System Configuration
 Serial MS-DOS Commands
 Parallel Menu
Printer I/O Configuration
Serial Configuration
 Pacing Handshaking
 Serial Cable Pin-outs
DB-9 RS-232 Serial Connection HP LaserJet
 C2932A Cable Pinout for 9 to 9 Pin Connector
DB-25 RS-232 Serial Connection HP LaserJet 4 Plus/5
 17255D Cable Pinout for 25 to 25 Pin Connector
DB-25 Serial Connection HP LaserJet
 10 C2933A Cable Pinout for 9 to 25 Pin Connector
 RS-422A Serial Configuration LaserJet 4 only
11 RS-422A Cable Pinout
 Modular I/O Configuration
 Printer Drivers
Install Printer Drivers and Utilities
How to Obtain Printer Drivers
 DOS Utilities
 Packing Checklist
Packing the Printer
Repackaging Instructions
Canada
 Installing The Optional Lower Cassette
12 Installing the Printer on the Lower Cassette
 14 Adjust the cassette for the paper size you want to load
13 Pull the cassette tray straight out of the printer
 Configuration
 Exec
 20 Slide the cassette back into the Lower Cassette assembly
 Envelope Feeder Installation
21 Remove the Black Plastic Cover
 LaserJet 4 and 4 Plus
LaserJet
 Simm Installation
Protecting the Simm Board
 23 Identifying the Four Simm Slots
 12Minimum Memory Recommendations LaserJet 4 Only
PCL Only PostScript Only Resolution 300 dpi 600 dpi
Memory Requirements
 HP LaserJet 4+/4M+/5/5M/5N
Simm boards
HP LaserJet 4/4M
 Accessing the Simm Slots
Installing the Simm Boards
 25 Installing the Simm Board
 Running a Self Test Printout
Testing a Simm Board
Memory Simm
 Personality Simm PostScript
 Troubleshooting a Simm Board
Service / Error Messages
 Configuration
 Preventive Maintenance
 Selected Service Consumables
Life Expectancy of Consumables
 Service Checkpoints
Maintenance Checkpoints
 Cleaning Your Printer
 Toner Cartridge
 Saving Toner with EconoMode HP LaserJet 4 Plus and 5 Only
Storing the Toner Cartridge
 Installing the Toner Cartridge
Removing the Toner Cartridge Sealing Tape
 Inserting the Toner Cartridge
 Non-HP Toner Cartridges
 Clearing the Toner LOW Message
 Periodic Maintenance Procedures
Removing the MP Tray Tray 1 Pickup Roller
 Removing the MP Tray Tray 1 Separation Pad
 Removing the PC Tray 2 Pickup Roller
 Removing the Lower Cassette LC or Tray 3 Pickup Roller
Removing the Lower Cassette Pickup Roller
 Removing and Replacing the Transfer Roller
Replacing the Transfer Roller
 Removing the Transfer Roller
Replacing the Transfer Roller
 Functional Overview
 DC Controller System
 DC Controller Loads
DC Controller Loads
 Serial Data Communication
Serial Data Flow
 Solenoid Description
Solenoid Signals
Solenoids
 Photosensors
LJ 4 / 4 Plus
 Photosensor Signals
Sensor Description
 Microswitches
 Microswitch Signals
Switch Description
Switch Settings for PC Tray 2 and LC Tray
PC Tray 2 and LC Tray 3 Tray Size Sensing System
 Motors
 Motors Description
Paper Jam Detection
Motors
 Formatter System
Control
 Formatter PCA-Functional Areas
 Memory Management
Data Processing
 PJL Overview
 Image Formation System
Image Formation System
 Photosensitive Drum
Drum Sensitivity
 Cleaning Stage
Drum Cleaning Station
 Conditioning Stage
Primary Charging Roller
 Writing Stage
 11 Drum Signals
 Developing Stage
12 Image Development
 13 Developing Potentials
 Transferring Stage
14 Transfer of the Toner Image and Paper Separation
 Fusing Stage
15 Fusing the Toner to the Paper
 Paper Feed System
 16 Input Paper Feed System Diagram
 17 Paper Feed Assembly Sectional View Part Description
 Printing from the MP Tray Tray
18 MP Tray Tray 1 to Output Tray Paper Path
 Printing from the PC Tray Tray
 Power System
 20 Power System Block Diagram
 Basic Sequence of Operation
Standard Printer Operation
 Timing Diagrams
 21 MP Tray Timing Diagram-HP LaserJet 4/4M
 This a 2 panel pull-out
 Standby Period
PowerSave
Warmup Period
 Initial Rotation Period
Page
 Print Period
Page
 Last Rotation Period
 Removal and Replacement
U t i o n T e
 Required Tools
Required Tools
Hardware Review
 Printer Hardware Descriptions
Drawing Description Purpose
 LJ 4/4 Plus
Removing the Covers
Right Side Cover Removal
 Top Cover Removal
Front Top Cover Screws and Latches
 Control Panel Cable
 Left Side Cover Removal
Left Side Cover Latches
 Rear Door Removal
Releasing the Door Support
 7a Releasing the Door Hinge LaserJet 4/5
 Font Door Cover Removal LJ 5 Right Front Cover Removal
Font Door Removal LaserJet 4 shown
 Font Door Cover Latches
 Multi-Purpose MP Tray Tray 1 Door Removal
10 Removing the MP Tray Door
 Multi-Purpose MP Tray Tray 1 Removal
11 Remove the Crossmember Bracket
 12 Rotate the Tray Down to Release the Hinge from its Slots
 Power Supply Removal
Assemblies Removal
 13b Remove the Sheet Metal Plate LaserJet 4 Plus/5
 15 6-wire and 3-wire Connectors for the Power Supply
 Paper Feed Assembly Removal
16 Paper Feed Assembly Screws and Connectors
 17 MP Tray Opening Cover
 18 Paper Feed Assembly Screws numbered
 High Voltage Power Supply Hvps Removal
19 Hvps Screws 2 and Latches 2 Bottom View
 Fuser Assembly Removal
U t i o n
 Control Panel and Overlay Removal
21 Control Panel Latches
 22 Changing the Control Panel Overlay
 Removing the SIMMs Door
LaserJet
 23b Opening the SIMMs Door LaserJet 4 Plus
LaserJet 4 Plus/5
 Formatter Cage Removal
24a Formatter Cage Screws Right Side View LaserJet 4 T e
 24b Formatter Cage Screws Right Side View LaserJet 4 Plus
 Formatter PCA Removal
 LaserJet 4 Formatter PCA
25a Formatter Cover and PCA Mounting Screws LaserJet
 25b Interface Connector Support Screws LaserJet T e
 Plus
Interface Connector Support Screws LaserJet
LaserJet 4 Plus and 5 Formatter PCA
 27a DC Controller Connectors/Retaining Clips LaserJet T e
DC Controller Removal
 Removal and Replacement
 DC Controller Installation
 28 Leading Edge Registration Adjustment Dimensions
 Main Motor Assembly Removal
30 Main Motor Assembly
 Gear Assembly Removal
31 Gear Assembly Screws Located behind Main Motor
 Fan Connector
Fan Removal
 33 Exhaust Fan Removal Laser Jet 4 shown
 Output Assembly Removal
34 Output Assembly Removal
 Paper Exit Sensor PS3 Removal
Exit Sensor
 Scanner Assembly Removal
36 Scanner Assembly Removal
 Lower Cassette Assemblies
Lower Cassette Sensor PCA Removal
 Lower Cassette Pickup Motor Removal
38 Lower Cassette Upper Front Cover
 39 Lower Cassette Motor
 Replacing Fuser Assembly Parts
 Fuser Assembly Configuration
Fuser Assembly Configuration
Fuser Assembly
 Removing the Fuser Roller Heat Lamp
41 Fuser End Cap Removal LaserJet 4 only
 42 Fuser Wire Harness Cover Removal LaserJet
 42b Fuser Cover End Latches LaserJet 4 Plus
 43 Left Side Fuser Cover
 Gear Side Heat Lamp Connector
Bushing on the left side of the Fusing Roller
 Wires in the gear cover slots
Fuser Gear Cap Removal
 Fuser Assembly Thermoswitch Removal
46 Fuser Thermoswitch Connectors
 47 Thermistor Connector
Thermistor Removal
 48a Upper Fuser Frame Removal LaserJet
 48b Upper Fuser Frame Removal LaserJet 4 Plus
 Paper Control PCA Removal
49 Paper Control PCA Retaining Screws and Latches
 Sensor PCA Removal
50 Sensor PCA Removal
 PS1 and PS2 Sensor Assembly Removal
51 Removing the PS1/PS2 Sensor Assembly
 High Voltage Contact Plate Hvcp and Paper Guide Removal
 52 Guide Plate Cover Screw
 53 Paper Guide Rollers
 54 Cross Member Screws
 55 Left Toner Cartridge Guide Plate Screw
 56 High Voltage Contact and Feed Guide Assembly Latches
 57 Orientation of Hvcp and Left Guide Plate
 Interconnect PCA Removal
58 Right Side PC tray Rail Cover printer on right side
 59 Interconnect PCA latches and AC Connector Mounting Pins
 60 Correct Orientation of AC Connector Notch at Upper Left
 Removal and Replacement
 LaserJet 5 Error Map
Message on LJ 5/5M/5N Recommendations
 LaserJet 5 Error Map
 LaserJet 5 Error Map 7-C
 LaserJet 5 Error Map
 Pre-Troubleshooting Procedures
Preliminary Operating Checks
 Printer Message Troubleshooting
Message Symptoms and Recommendations
Printer Message Summary Table
Printer Messages
 Returns all printer settings to Printing Menu settings,
 This message is displayed when the MIO AUX IO card is
 For serial/Bi-Tronics parallel configuration, the computer
 Refer to the Product Family Compatibility
 Indicates a communications problem between the DC
 Printer identified an internal service error. If this error
 An error state. To clear this message, remove
 Clearable Warnings
 Clearable Warning Messages
Meaning
 Printer Message Troubleshooting Procedures
Blank Display
Blank Display
Checks Action
 MP/PC/LC Tray 1/2/3 Load Message
 MP/PC/LC Tray 1/2/3 Load Message Checks
Figures 7-14 and 7-15 for locations
 Cassette Size Switches SW603, SW604, SW605 Functional Check
PC Tray Size Sensing Microswitches Location
 Switch Logic for Cassette Size
Paper Size Sensing Lower Cassette
 PC Empty Sensor PS2 Functional Check
PS4 Check MP Tray Empty Sensor
 Printer Open Message
Printer Open Checks
 SW601 Functional Check
Location of the Top Cover Closed SW601 Actuator
 Paper JAM Message
PS1 and PS3 Paper Path Sensors & PS5 Paper End Sensor
 Paper Jam Troubleshooting Checklist
Jam Location Checks and Action Required
 PS1 Input/Registration Sensor Check
PS1 Input/Registration Sensor
 PS3 Exit Sensor Check
Pickup Motor Functional Test M2
 Lower Cassette Functional Check
 No EP Cart Message
Toner Low Message
 Callout Assembly
Toner Cartridge Components
 Error Message
 Error Checks
Error Message Recommended Action
 Service Error Fuser Malfunction
 Service Fuser Malfunction Checks
 Fuser Assembly Connector
1151 Error Beam Detect Checks
 Error Scanner Malfunction
Laser/Scanner Assembly Functional Checks
 57 or 57.1 Service Message Main Motor Failure
Main Motor Functional Checks
 58 or 57.2 Service Fan Failure
 Image Defect Summary
 Image Defect Summary
 Image Defect Summary
 Any Faint Print Condition
Black Pages
Possible Cause Action
 Faulty Registration
 Right-Hand Image Missing
Small Print Voids
Random Horizontal Black Lines
Vertical White Streaks
 Repetitive Defects
 Smeared Print/Improper Fusing
Distorted Print
 22Black Pages with Horizontal White Strips
Image Skew
 Improperly Sized Image
PS5 Check MP Tray Paper End Sensor Functional Test
 PS5 Test Sheet
 Vertical Dark Streaks
Large Print Voids
 LaserJet Family Paper Specifications
Background Scatter
 White or Blank Pages
 Image Formation Troubleshooting
Half Self-Test Functional Check
 Drum Rotation Functional Check
 High Voltage Power Supply Assembly
29High Voltage System Checks
 Test Message
Interface Troubleshooting
Communications Check
 Serial MS-DOS Commands
AUTOEXEC.BAT Standard Configurations
Parallel DOS Commands
 Communications Checks
Communications Checks
 HP LaserJet printers are not designed to work
 MIO Troubleshooting
Troubleshooting Hints
 Explanation of Self Test Printout
 10 MIO Staus Information on the Self Test Printout
 Troubleshooting Aids
Component Locations
 12 Major Assembly and Connector Locations 2 Number Part
 13 Major Assembly and Connector Locations 3 Number
 Switch Locations
 15 Optional 500 Sheet Lower Cassette Number Part
 16 DC Controller PCA Layout-LaserJet 4/4M Number Part
 17 DC Controller PCA Layout -LaserJet 4 Plus/5 Number Part
 High Voltage PCA Layout
Number Part
 Repetitive Defect Template
19 Repetitive Defect Ruler
 20 Main Wiring Diagram LJ 4+/5 only
 Voltage Test Points
Measuring the DC Voltage Levels
TB 201Voltages
Color Pin Number
 Troubleshooting
 Parts and Diagrams
How To Use the Parts Lists
 Parts Lists and Illustrations
1a Field-Replaceable Assemblies 1
 1b Field-Replaceable Assemblies 2
 Field-Replaceable Assemblies
Exchng # Description
 Field-Replaceable Assemblies
 Covers and Panels
 Covers and Panels
 3a Top Cover Assembly for LaserJet 4/4+
 Top Cover Assembly
 Cable, Display Panel
 3b Top Cover Assembly for LaserJet
 Overlay Language
 4a Internal Components 1
4aInternal Components Section
 RB1-2111-030CN Shutter, arm RB1-2114-000CN
 4b Internal Components 2
 Lnternal Components Section
 4c Internal Components 3
 Internal Components Section
 C2038-60004 LJ4+ C3919-67901
 4d Internal Components 4
 RB1-2251-000CN Block, Connecting RG5-0521-000CN
 Main Switch Assembly
 Main Switch Assembly
 6a Paper Feed Assembly 1
 6b Paper Feed Assembly 2
 Paper Feed Assembly
 MP Tray Tray 1 Assembly
MP Tray Tray 1 Assembly
 Paper Output Assembly
Paper Output Assembly
 Delivery Sensor Assembly
Delivery Sensor Assembly
 10 Fuser Assembly
 Fuser Assembly
 RS5-0232-000CN
 Accessory Parts
11 Lower Cassette Base Assembly
 Lower Cassette Base Assembly
 Lower Cassette Drive Assembly
Lower Cassette Drive Assembly
 13 Lower Cassette Assembly
13Lower Cassette Assembly
 14 Universal Cassette
 Simm Modules
Universal Cassette
Simm Memory
 Miscellaneous Parts and Accessories
Miscellaneous Parts and Accessories
 Parts List
Alphanumeric Parts List
 PCA
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 C2084C +/5
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 Parts and Diagrams
 Duplexer
 Figure A-1 Duplexer Paper Path
 Holding Tray
Switchback Assembly
Duplex Printing
 Figure A-2 Duplexer Major Components
 Figure A-3 Electrical Block Diagram
Electrical Overview
 Installing the Optional Duplexer
LJ 4 +
 Figure A-4 Duplexer Installation/Removal
 R n i n g U t i o n
Removal and Replacement
Required Tools
 Removing the Switchback Covers
Removing the Covers
 Removing the Side Cover on Power Side
Figure A-6
 Removing the Side Cover on Gear Side
Figure A-7 Side Cover on Gear Side
 Figure A-8 Latch Location on Underside of Duplexer
 Removing the Back Cover
Removing the Front Cover
 Removing Internal Duplexer Components
Removing the Fan/Motor/Solenoid/Sensor
 Removing the Switchback Paper Guide
Figure A-11 Switchback Paper Guide
 Removing the Paper Guide Assembly
Figure A-12 Wire Routing and Upper Switchback Guide Screw
 Removing the Paper Roller
Figure A-13 Solenoid Arm
 Figure A-14 Upper Paper Guide Sheet Metal
 Figure A-15 Gears on Paper Roller
 Removing the Control PCA
Figure A-16
 Figure A-17 Control PCA
 Removing the Power PCA
Figure A-18 Power PCA
 Figure A-19 Plate on Power PCA Side of Duplexer
Removing the Holding Tray Center Paper Guide
 Removing the Holding Tray Belt
Figure A-20 Holding Tray Belt Cover Plate
 Figure A-21 Holding Tray Gears and Belt
 Removing the Holding Tray Paper Sensor
Figure A-22 Holding Tray Paper Sensor
 Removing the Switchback Assembly
Figure A-23 Switchback Assembly Hinge Pins
 Parts and Diagrams for the Duplexer
 Figure A-24 Duplex External Covers
 Table A-24 Duplex External Covers Description
 Figure A-25a Duplex Feeder Assembly 1
 Figure A-25b Duplex Feeder Assembly 2
 Table A-25 Duplex Feed Assembly Description
 RF1-3817-00017
 Figure A-26a Duplex Switchback Assembly 1
 Figure A-26b Duplex Switchback Assembly 2
 Table A-26 Duplex Switchback Assembly Description
 Description
 LaserJet 5/5M/5N Printer
 Product Information
Table B-1
 HP LJ4M+ HPLJ5 HPLJ5M HPLJ5N
 Table B-2
LaserJet 4? LaserJet 4 Plus? LaserJet 5?
 LaserJet 5/5M/5N Printer B-5
 Table B-4
Table B-3Printer Dimensions
HP LaserJet 5 / 5M / 5N
 Table B-6
Table B-5
 Table B-7
HP LaserJet 5/5M/5N Part Number Documents-Description
 Laser Statement Sweden/Finland
 Control Panel Layout
Control Panel Keys
 Table B-8 Control Panel Keys Explanation
Printer back on line
 Key Explanation
Value +
 To change a control panel setting
 Figure B-3 Control Panel Menu Map
 Printing Menu
TableB-10 Printing Menu Items
 Media size
 PCL Fonts Menu
Table B-11 PCL Fonts Menu Items
 PostScript Menu
Job Menu
Table B-12 PostScript Menu Items
Table B-13 Job Menu Items
 Configuration Menu
Table B-14 Configuration Menu Items
 Auto OFF
 Memory Configuration Menu
Table B-15 Memory Configuration Menu Items
 Table B-17 Serial Menu Items
Serial Menu
Table B-16 Parallel Menu Items
 Resets Menu
Table B-18 Resets Menu Items
 Test Menu
Table B-19 Test Menu Items
 LaserJet 5/5M/5N Printer B-25
 Service Mode
 Setting the Cold Reset Default
 Big Data
Diagnostics
Skip Demo
 Programming a Flash Simm
 Changing the Control Panel Display Language
 Nvram Init
 Table B-20 Self Test Printout Items for the HP LaserJet
 Figure B-4 HP LaserJet 5 PCL Self Test Printout
 Infrared Communication
 Figure B-5 IR Data Flow
System Requirements
 To Print Using the Infrared Port
Figure B-6 IrDA Port Location
 Figure B-7 IrDa Port Ranges
 Troubleshooting IR Printing Problems
 Figure B-8 Infrared Test Tool
Page
 Table B-21 Solutions for Infrared Not Responding Situation
Infrared Port Not Responding
 Situation Solution
 Index
Index-1
 Index-2
 Index-3
 Index-4
 Index-5
 Index-6
 Index-7
 Index-8
 SN-1 Service Notes
 SN-2 Service Notes
 SN-3 Service Notes
 SN-4 Service Notes
 SN-5 Service Notes
 SN-6 Service Notes
 SN-7 Service Notes
 SN-8 Service Notes
 C3916-90984