Hp 6L User Manual

HP LaserJet 5L and 6L Printer
Service Manual

Service Manual

HP LaserJet 5L HP LaserJet 6L
(C3941A) (C3990A)

© Copyright Hewlett-Packard
Company 1997

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

Publication number
C3990-90991

First edition, May 1997

Warranty

The information contained in
this document is subject to
change without notice.

Hewlett-Packard makes no
warranty of any kind with
regard to this material,
including, but not limited to,
the implied warranties or
merchantability and fitness for
a particular purpose.

Hewlett-Packard shall not be
liable for errors contained
herein or for incidental or
consequential damaged in
connection with the furnishing,
performance, or use of this
material.

WARNING

Electrical Shock Hazard
To avoid electricalshock, use

only supplied power cords and
connect only to properly
grounded (3-hole) wall outlets.

Hewlett-Packard Company
11311 Chinden Boulevard
Boise, Idaho 83714

Conventions

This manual uses the following conventions:

Color is used to emphasize items which are important to the material under

discussion.
The names of major printer parts and assemblies are CAPITALIZED.
Bold is used for emphasis, particularly in situations where italic type would be

confusing.
Italic type is used to indicate related documents or emphasis.

Note

Caution

WARNING!

Notes contain important information set off from the text.

Caution messages alert you to the possibility of damage to equipment or loss of data.

Warning messages alert you to the possibility of personal injury.

iii

Chapter Descriptions

1 Product Information

Orientation to the printer, as well as the service and repair philosophy, is discussed.
Information on obtaining assistance and warranty is also here.

2 Site Requirements

Here are recommendations pertaining to installation requirements.

3 Operating Overview

This chapter has detailed information about the Control Panel. Sample self tests and
printer reset information are also included.

4 Maintenance

Turn to this chapter for information about printer cleaning and care.

5 Functional Overview

Here you will find the basic theory-of-operation information required to understand
the various printer systems and how they function together.

6 Removal and Replacement

This chapter contains the step-by-step procedures for replacing printer field
replaceable units (FRUs). Assemblies are grouped by location in the printer.

7 Troubleshooting

Diagnose printer problems here. A preliminary troubleshooting table is followed by
error messages, image defect samples, and diagnostic tools.

8 Parts and Diagrams

Look here to find any field replaceable unit (FRU) in the printer. Exploded view
drawings are accompanied by complete part number tables.

A Parts Index

All parts are sorted and cross-referenced here by part number and name.

B Regulatory Information

Here are required statements regarding RFI and laser safety.

C Service Notes

Service Notes for HP LaserJet 5L concerning paper jams appear here.

Subject Index

Use the subject index to quickly locate any information in the manual.

iv

List of Figures

Figure 1-1 HP LaserJet 5L Model and Serial Numbers . . . . . . . . . . . . 1-4

Figure 1-2 HP LaserJet 6L Model and Serial Numbers . . . . . . . . . . . . . 1-5

Figure 1-3 Front/Side Views of the Printer . . . . . . . . . . . . . . . . . . 1-7

Figure 1-4 Front Door Assemblies . . . . . . . . . . . . . . . . . . . . . . 1-8

Figure 1-5 Back View of the Printer . . . . . . . . . . . . . . . . . . . . . . 1-9

Figure 2-1 Printer Space Requirements . . . . . . . . . . . . . . . . . . . . 2-4

Figure 2-2 Toner Cartridge Distribution . . . . . . . . . . . . . . . . . . . . 2-6

Figure 3-1 Self-test Page for HP LaserJet 5L . . . . . . . . . . . . . . . . . 3-7

Figure 3-2 Self-test Page for HP LaserJet 6L . . . . . . . . . . . . . . . . . 3-8

Figure 3-3 Engine Test Button . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Figure 4-1 Five Percent Text Coverage . . . . . . . . . . . . . . . . . . . . 4-4

Figure 4-2 Static Eliminator Teeth . . . . . . . . . . . . . . . . . . . . . . 4-8

Figure 5-1 Printer Functional Block Diagram . . . . . . . . . . . . . . . . . 5-3

Figure 5-2 DC Controller Loads . . . . . . . . . . . . . . . . . . . . . . . . 5-4

Figure 5-3 EconoMode vs Normal Mode . . . . . . . . . . . . . . . . . . 5-10

Figure 5-4 Image Formation Block Diagram . . . . . . . . . . . . . . . . 5-12

Figure 5-5 Simplified Paper Path . . . . . . . . . . . . . . . . . . . . . . 5-16

Figure 5-6 Solenoid and Sensors . . . . . . . . . . . . . . . . . . . . . . 5-17

Figure 5-7 General Timing Diagram – HP LaserJet 5L . . . . . . . . . . . 5-20

Figure 5-8 General Timing Diagram – HP LaserJet 6L . . . . . . . . . . . 5-21

Figure 6-1 Phillips and Posidriv screwdrivers . . . . . . . . . . . . . . . . . 6-4

Figure 6-2 Back Cover Removal (1 of 2) . . . . . . . . . . . . . . . . . . . 6-6

Figure 6-3 Back Cover Removal (2 of 2) . . . . . . . . . . . . . . . . . . . 6-7

Figure 6-4 EP Door Assembly Removal . . . . . . . . . . . . . . . . . . . 6-8

Figure 6-5 Memory Door Removal . . . . . . . . . . . . . . . . . . . . . . 6-9

Figure 6-6 Main Cover and Paper Input Assembly Removal . . . . . . . . 6-10

Figure 6-7 Control Panel Removal . . . . . . . . . . . . . . . . . . . . . 6-11

Figure 6-8 Exit Roller Removal . . . . . . . . . . . . . . . . . . . . . . . 6-12

Figure 6-9 Delivery Assembly Removal (1 of 2) . . . . . . . . . . . . . . 6-13

Figure 6-10 Delivery Assembly Removal (2 of 2) . . . . . . . . . . . . . . 6-14

Figure 6-11 Fuser Pressure Plate Removal . . . . . . . . . . . . . . . . . . 6-15

Figure 6-12 Fuser Pressure Plate Replacement . . . . . . . . . . . . . . . . 6-16

Figure 6-13 Heating Element Removal (1 of 3) . . . . . . . . . . . . . . . 6-17

Figure 6-14 Heating Element Removal (2 of 3) . . . . . . . . . . . . . . . 6-18

Figure 6-15 Heating Element Removal (3 of 3) . . . . . . . . . . . . . . . 6-19

Figure 6-16 Pressure Roller Removal . . . . . . . . . . . . . . . . . . . . . 6-20

Figure 6-17 Face-Up/Face-Down Lever Replacement . . . . . . . . . . . . 6-21

Figure 6-18 Fuser Exit Roller Removal . . . . . . . . . . . . . . . . . . . 6-22

Figure 6-19 Paper Exit Sensor Flag Replacement . . . . . . . . . . . . . . 6-23

Figure 6-20 Laser/Scanner Assembly Removal . . . . . . . . . . . . . . . 6-24

Figure 6-21 Solenoid Removal (1 of 2) . . . . . . . . . . . . . . . . . . . . 6-25

Figure 6-22 Solenoid Removal (2 of 2) . . . . . . . . . . . . . . . . . . . . 6-26

Figure 6-23 Pickup Roller Assembly Removal (1 of 2) . . . . . . . . . . . 6-27

v

Figure 6-24 Pickup Roller Assembly Removal (2 of 2) . . . . . . . . . . . 6-28

Figure 6-25 Paper Pickup Roller Assembly Replacement (Inside/Front View) 6-29

Figure 6-26 Paper Feed Frame Removal (1 of 4) . . . . . . . . . . . . . . 6-30

Figure 6-27 Paper Feed Frame Removal (2 of 4) . . . . . . . . . . . . . . 6-31

Figure 6-28 Paper Feed Frame Removal (3 of 4) . . . . . . . . . . . . . . 6-32

Figure 6-29 Paper Feed Frame Removal (4 of 4) . . . . . . . . . . . . . . 6-33

Figure 6-30 Transfer Roller Guide & Transfer Roller Removal

(Inside/Back View) . . . . . . . . . . . . . . . . . . . . . . . 6-34

Figure 6-31 Kick Plate Removal . . . . . . . . . . . . . . . . . . . . . . . 6-35

Figure 6-32 Kick Plate Spring Replacement . . . . . . . . . . . . . . . . . 6-36

Figure 6-33 Separation Pad Removal . . . . . . . . . . . . . . . . . . . . 6-37

Figure 6-34 Subpad Removal . . . . . . . . . . . . . . . . . . . . . . . . . 6-38

Figure 6-35 Feed Assembly Removal (1 of 3) . . . . . . . . . . . . . . . . 6-39

Figure 6-36 Feed Assembly Removal (2 of 3) . . . . . . . . . . . . . . . . 6-40

Figure 6-37 Feed Assembly Removal (3 of 3) . . . . . . . . . . . . . . . . 6-41

Figure 6-38 Memory Door Guide Removal . . . . . . . . . . . . . . . . . 6-42

Figure 6-39 Motor Removal . . . . . . . . . . . . . . . . . . . . . . . . . 6-43

Figure 6-40 DC Controller Removal (1 of 3) . . . . . . . . . . . . . . . . 6-44

Figure 6-41 DC Controller Removal (2 of 3) . . . . . . . . . . . . . . . . 6-45

Figure 6-42 DC Controller Removal (3 of 3) . . . . . . . . . . . . . . . . 6-46

Figure 6-43 Formatter Board Removal . . . . . . . . . . . . . . . . . . . . 6-47

Figure 7-1 Paper Path and Components . . . . . . . . . . . . . . . . . . . . 7-5

Figure 7-2 DC Controller PCA Components . . . . . . . . . . . . . . . . . 7-6

Figure 7-3 Heating Element Resistance Check . . . . . . . . . . . . . . . 7-11

Figure 7-4 Engine Test . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-21

Figure 7-5 Toner Cartridge High Voltage Connection Points (1 of 2) . . . 7-24
Figure 7-6 Toner Cartridge High Voltage Connection Points (2 of 2) . . . 7-25

Figure 7-7 Overriding PS204 and SW101 . . . . . . . . . . . . . . . . . 7-27

Figure 7-8 Repetitive Image Defect Ruler . . . . . . . . . . . . . . . . . 7-28

Figure 7-9 Repetitive Image Defect Ruler . . . . . . . . . . . . . . . . . 7-29

Figure 8-1 Major Assembly Locations . . . . . . . . . . . . . . . . . . . . 8-7

Figure 8-2 Covers and Doors . . . . . . . . . . . . . . . . . . . . . . . . . 8-8

Figure 8-3 Internal Components (1 of 3) . . . . . . . . . . . . . . . . . . 8-10

Figure 8-4 Internal Components (2 of 3) . . . . . . . . . . . . . . . . . . 8-12

Figure 8-5 Internal Components (3 of 3) . . . . . . . . . . . . . . . . . . 8-14

Figure 8-6 DC Controller/Formatter and Cables . . . . . . . . . . . . . . 8-16

Figure 8-7 Pickup Roller Assembly . . . . . . . . . . . . . . . . . . . . . 8-18

Figure 8-8 Feed Assembly . . . . . . . . . . . . . . . . . . . . . . . . . 8-20

Figure 8-9 Separation Guide Assembly . . . . . . . . . . . . . . . . . . . 8-22

Figure 8-10 Delivery Assembly . . . . . . . . . . . . . . . . . . . . . . . 8-24

Figure B-1 VCCI Statement (Japan) . . . . . . . . . . . . . . . . . . . . . B-4

vi

List of T a bles

Table 1-1 Printer Features . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Table 1-2 Paper Capacities and Sizes . . . . . . . . . . . . . . . . . . . . 1-3

Table 1-3 Performance Specifications . . . . . . . . . . . . . . . . . . . . 1-6

Table 1-4 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . 1-6

Table 1-5 Acoustic Emissions . . . . . . . . . . . . . . . . . . . . . . . . 1-6

Table 1-6 Related Documentation . . . . . . . . . . . . . . . . . . . . . 1-11

Table 2-1 Environmental Requirements . . . . . . . . . . . . . . . . . . . 2-3

Table 2-2 Printer Dimensions . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Table 3-1 Indicator Lights (1 of 2) . . . . . . . . . . . . . . . . . . . . . . 3-4

Table 3-1 Indicator Lights (Continued 2 of 2) . . . . . . . . . . . . . . . . 3-5

Table 3-2 Front Panel Button Usage . . . . . . . . . . . . . . . . . . . . . 3-6

Table 4-1 Life Expectancy of Consumables . . . . . . . . . . . . . . . . . 4-3

Table 4-2 Cleaning Printer Components . . . . . . . . . . . . . . . . . . . 4-7

Table 5-1 Solenoid and Photosensors . . . . . . . . . . . . . . . . . . . 5-17

Table 5-2 Printer Timing . . . . . . . . . . . . . . . . . . . . . . . . . . 5-19

Table 7-1 Printer Status Messages (1 of 2) . . . . . . . . . . . . . . . . . . 7-8

Table 7-2 Printer Status Messages (Continued 2 of 2) . . . . . . . . . . . . 7-9

Table 7-3 Unclearable Error . . . . . . . . . . . . . . . . . . . . . . . . . 7-9

Table 7-4 Service and Error Messages (1 of 3) . . . . . . . . . . . . . . 7-10

Table 7-4 Service and Error Messages (Continued 2 of 3 ) . . . . . . . . 7-11

Table 7-4 Service and Error Messages (Continued 3 of 3) . . . . . . . . . 7-12

Table 7-5 High-Voltage Power Supply Check . . . . . . . . . . . . . . . 7-24

Table 7-6 Paper Curl Troubleshooting . . . . . . . . . . . . . . . . . . . 7-26

Table 7-7 Cable Pinouts . . . . . . . . . . . . . . . . . . . . . . . . . . 7-30

Table 7-8 Cable Pinouts . . . . . . . . . . . . . . . . . . . . . . . . . . 7-31

Table 8-1 Accessories and Supplies . . . . . . . . . . . . . . . . . . . . . 8-5

Table 8-2 Common Fasteners Used in the Printer . . . . . . . . . . . . . . 8-6

Table 8-3 Covers and Doors . . . . . . . . . . . . . . . . . . . . . . . . . 8-9

Table 8-4 Internal Components (1 of 3) . . . . . . . . . . . . . . . . . . 8-11

Table 8-5 Internal Components (2 of 3) . . . . . . . . . . . . . . . . . . 8-13

Table 8-5 Internal Components (3 of 3) . . . . . . . . . . . . . . . . . . 8-15

Table 8-6 ECU Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-17

Table A-1 Alphabetical Parts List . . . . . . . . . . . . . . . . . . . . . . A-2

Table A-2 Numerical Parts Index . . . . . . . . . . . . . . . . . . . . . . A-6

vii

viii

Product Information

Contents

Printer Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Paper Capacities and Sizes . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

Model and Serial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

Product Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

Front/Side Views of the Printer . . . . . . . . . . . . . . . . . . . . . . . . 1-7

Front Door Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8

Back View of the Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9

Service Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

Parts Exchange Program . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

Ordering Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

Ordering Consumables . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

Ordering Related Documentation . . . . . . . . . . . . . . . . . . . . . 1-10

Technical Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12

Worldwide Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13

North American Response Center . . . . . . . . . . . . . . . . . . . . . 1-13

Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

Warranty Exclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

Warranty Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

Voltage Conversions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

1

Product Information 1-1

1-2 Product Information

Printer Features

Table 1-1 Printer Features

Features Descriptions

Print Speed 4 ppm (HP LaserJet 5L); 6 ppm (HP LaserJet 6L)
Text & Graphics Resolution 300 or 600 dpi
Printer Language Enhanced PCL 5
Monthly Usage (pages) 4,000 pages (HP LaserJet 5L); 6,000 pages (HP LaserJet 6L)

1

Information

Product

Memory:

Standard

Maximum Memory

Capacity
Internal Typefaces 26 Scalable Typefaces
Standard Interfaces Parallel(Bi-tronics)
PowerControl SleepMode
Control Panel 3 LEDs

EconoMode (toner saving) Yes

1 Printermemory is optimized with Memory Enhancement technology (MEt).
2

JEDIA (Japanese Electronic Device Industry Association) is a group of DRAM suppliers who have

standardized DRAM and other CMOS products.

1

1 Mbyte RAM
9 Mbyte total (available in increments of 1, 2, 4, and 8 Mbytes)
5 V JEDIA card

1 Front Panel Button

Paper Capacities and Sizes

Table 1-2 Paper Capacities and Sizes

Features Descriptions

Paper Input Bin Capacity Holds up to 100 sheets of regular weight paper or up to

Paper Output Bin Capacity Holds up to 100 sheets
Single Sheet Input Bin 1
Minimum PaperSize 3x5 in.(76 mm x 127 mm)
Maximum PaperSize 8.5x14 in.(216 mm x 356 mm)

(70nsec)

2

10 envelopes

Product Information 1-3

Figure 1-1

Identification

Model and Serial

The model number and serial numbers are listed on identification labels located on
the bottom of the printer. The model number is alphanumeric, such as C3941A for
the HP LaserJet 5L printer, and C3990A for the HP LaserJet 6L printer.

The serial number contains information about the Country of Origin, the Revision
Level, the Production Code, and production number of the printer.

The labels also contain power rating and regulatory information.

HP LaserJet 5L Model and Serial Numbers

1-4 Product Information

Figure 1-2

1

Information

Product

HP LaserJet 6L Model and Serial Numbers

Product Information 1-5

Specifications

Table 1-3 Performance Specifications

Category Specification

Print Speed*: HP LaserJet 5L
Print Speed*: HP LaserJet 6L

Monthly Usage (Duty Cycle): HP LaserJet 5L
Monthly Usage (Duty Cycle): HP LaserJet 6L

Life Expectancy of Toner Cartridge (pages)** 2,500 pages @ 5% coverage
First Print A4 <23 seconds

* Actual speed depends on data complexity and software handling efficiency.
** Toner cartridge life can be extended by using EconoMode.

Table 1-4 Electrical Specifications

Volts Freq Amps Watts (typical)

120 Vac ± 10%
100 Vac ±10%

220 Vac ± 10%
240 Vac ± 10%

*Minimum recommended circuit capacity for product.

50/60 Hz ± 2Hz
50/60 Hz ± 2Hz

50 Hz ± 2Hz
50 Hz ± 2Hz

4 ppm
6 ppm

4,000 pages
6,000 pages

Letter <23 seconds

3.5 @ 120v* printing = 100 (5L) 150 (6L)
SleepMode = 6 (5L) 4 (6L)

1.8 @ 230v printing = 100 (5L) 150 (6L)
SleepMode = 6 (5L) 4 (6L)

Table 1-5 Acoustic Emissions

During Printing 5.6 Bels Sound Power Level( per ISO 9296)
During Standby & SleepMode

1-6 Product Information

Silent

Figure 1-3

Product Overview

1

Information

Product

Front/Side Views of the Printer

1.Paper Input Support 7.Front Panel Button 13.Front Output Slot (face-up)

2.Paper Output Support 8.Paper Output Bin

3.Paper Guides 9.Paper Path Lever

4.Error (top) Light 10.Serial and Model Number (under printer)

5.Data (middle) Light 11. Paper Input Bin

6.Ready (bottom) Light 12.Single Sheet Input Slot

Product Information 1-7

Figure 1-4

Front Door Assemblies

14. Paper Release Lever 16.Transfer Roller (do not touch)

15.Toner Cartridge Compartment 17. EP Door

1-8 Product Information

Figure 1-5 I

1

Information

Product

Back View of the Printer

18.Power Cable Connector 20. Memory Expansion Cover

19.Parallel Cable Connector

Product Information 1-9

Service Approach

Repair of the printer normally begins with the use of the printer’s internal
diagnostics in conjunction with the troubleshooting procedures in Chapter 7. Once a
faulty part is located, repair is generally accomplished by assembly level
replacement of Field Replaceable Units (FRUs). Some mechanical assemblies may
be repaired at the subassembly level. PCA component replacement is not supported
by Hewlett-Packard. Part numbers for all FRUs are located in Chapter 8 of this
manual.

Parts Exchange Program

HP offers remanufactured assemblies for some selected parts. These are identified
in Chapter 8 and can be ordered through HP’s Parts Direct Ordering (PDO), or Parts
Center Europe (PCE).

Ordering Parts

Field replaceable part numbers are found in Chapter 8 of this manual. Replacement
parts may be ordered through HP’s Parts Direct Ordering (PDO), or Parts Center
Europe (PCE).

Ordering Consumables

The printer has no consumables other than the toner cartridge, which may be
ordered directly from Hewlett-Packard. Refer to Chapter 8 for ordering information.

Ordering Related Documentation

Table 1-6 on the following page lists part numbers and where to order related
documentation. Phone numbers for the various sources are:

• Parts Direct Ordering (PDO)

1-800-227-8164 (U.S. only)

• Parts Center Europe (PCE)

(49 7031) 14-2253

• HP’s Distribution Center (HPD)

970-339-7009 (U.S. only)

• URL for HP Access: http://www.hp.com

• URL for Software and Support: http://www.hp.com/cposupport/cpoindex.html

1-10 Product Information

Table 1-6 Related Documentation

Description Part Number PDO PCE HPD

HP LaserJet Family Quick Reference
Service Guide

HP LaserJet 5L Printer
User’s Manual

HP LaserJet 6L Printer
User’s Manual

HP PCL5 Printer Language Technical
Reference Information Package

HP LaserJet Printer FamilyPaper
Specifications Guide

LaserJet Basic Hardware Training Course 5961-0880 X X
HPLJ 5L and 6L Hardware Training Kit C3990+49A-60001

HP LaserJet 6L Printer Service Manual Bundle
includes: Service Manual C3990-90991

Paper Specifications Guide 5021-0368
Quick Ref. Pocket Guide5021-0369

HP LaserJet 6L Printer NTSC Kit
includes: Box 9211-6385

6L Video Kit Label C3990-00010
6L Combined TestKit C3990-67902
6L Video Tape C3990-99002

HP LaserJet 6L Printer PAL Kit
includes: Cardboard Sleeve 5002-0556

VHS-PAL Tape 5010-6306
6L Spine Label C3990-00012
6L Face Label C3990-00013
6L Pal Kit Label C3990-00014

HP LaserJet 6L Combined Test Kit
includes: Return Envelopes 5002-0562

Final Exam 5960-6642
6L TestKit Label C3990-00011
6L TestBooks (5 total) C3990-90992

Note: the five Test Books are labeled “A” through “E.”
Specific Application Drivers X

5021-0369 X X

C3941-90901 X

C3990-90901 X

5010-3994 X X

5021-0368 X X X

(NTSC)

C3990+49A-60002

(PAL)

C3990-99001 X X

C3990-67901 X X

C3990-67903 X X

C3990-67902 X X

X
XX

1

Information

Product

Product Information 1-11

TechnicalAssistance

Online Services: for
24-hour access to
information overyour
modem, we suggest these
services.

Obtaining Software
Utilities and Electronic
Information:U.S. and
Canada

Asia-Pacific Countries

Australia/NewZealand
HP Direct Ordering for

Accessories and Supplies
HP Support Assistant

CD-ROM

HP Service Information To locate HP-authorized dealers, call [phone] (U.S.);[phone] (Canada).
HP Service Agreements Call [phone] (U.S.); [phone] (Canada).

HP FIRST: HP FIRST Fax will deliver detailed troubleshooting information on common software applications and troubleshooting tips

for your HP product. Call from any touch-tone phone and request up to three documents per call. These documents will be sent to the
fax of your choice.

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English outside of UK
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Indonesia
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WorldWideWeb URL—Printer drivers, updated HP printer software, and product and support
information maybe obtained from http://www.hp.com, or in Europe from http://www2.hp.com.In Japan
printer drivers may be obtained from ftp://www.jpn.hp.com/drivers/.Korea:www.hp.co.kr.Taiwan:
www.hp.com.tw,with a local driver website of www.dds.com.tw.

HP Bulletin Board Service—Our electronic download service providesconvenient access to HP
printer drivers, updated HP printer software, product information, and troubleshooting hints. Dial (208)
344-1691 (U.S. and Canada) and set your communication software to N,8,1.European Bulletin Board
Service numbers are listed at http://www2.hp.com.Taiwan: (886-2) 923-3233.Korea: HITEL or
CHOLIAN (Go HPK).Australia:(613) 9890 0276. New Zealand: [phone].

America OnLine—(America OnLine/Bertelsmann available in France,Germany, and UK)—Printer
drivers, updated HP printer software, and support documentation are available to help you answer
your HP product questions. Use Keyword HP to start your tour.

CompuServe—Printer drivers,updated HP printer software, and interactive sharing of technical
information withother members are available on CompuServe’s HP User’sforums (GO HP), or call
[phone] and ask for representative #51. (CompuServe is also available in the UK, France,
Belgium, Switzerland, Germany, and Austria.)

Phone: [phone] Mail: Hewlett-Packard
Fax: [phone] P.O.Box 1754

Fulfill Plus (65) 740-4477 (Singapore, Malaysia, Indonesia, Hong Kong).
Call [phone].

Call [phone] (U.S.) or [phone] (Canada).

This support tool offers a comprehensive online information system designedto provide technical and
product information onHP products. To subscribe to this quarterly service in the U.S.or Canada, call
[phone].Fulfill Plus, (65) 740-4477 (Singapore, Malaysia, Indonesia, Hong Kong).

[phone]
0660-8128
0800-1-1906
0800-1-7043
[phone]
(86 10) 6505 5280
800-10453
(31 20) 681-5792
9800-13134
05-905900
0130-810061
(852) 2506-2422
[phone]
(21) 352-2044
1678-59020
(813) 3335-8622

Korea
Malaysia
Netherlands
New Zealand
Norway
Philippines
Singapore
Spain
Sweden
Switzerland (German)
Switzerland (French)
Taiwan
Thailand
United Kingdom
United States

Greeley, CO 80632 USA

[phone]
[phone]
0800-22-2420
[phone]
800-11319
(65) 291-7951
(65) 275-7251
900-993123
020-795743
0800 55-1527
0800 55-1526
02-719-5589
[phone]
0800-960271
[phone]

1-12 Product Information

Worldwide Support

U.S.and Canada:
Customer Support &

Product Repair Assistance
(Please refer to the

warranty chapter of this
manual for additional
product repair
information.)

HP provides a free telephone support service during the warranty period.By calling a telephone number listed below, you will be
connected to a responsive team waiting to help you. If you require support after your warranty has expired, you can receive support
for a fee through the same telephone number.The fee is charged on a per-incident basis.When calling HP please have the following
information ready:

• Product name and serial number Date of purchase Description of the problem

Dutch Belgium: 02626 8806
English Ireland: 01 662 5525

French France: 04 50 43 9853

German Germany: 0180 5 25 81 43

Africa/Middle East
Argentina
Australia
Brazil
Canada
China

Czech Republic
Greece
Hong Kong
Hungary
India
Indonesia
Japan
Korea

Netherlands: 020 606 8751
UK: 0171 512 5202

International: 44 171 512 52 02
Belgium: 02 626 8807

Switzerland: 084 880 1111

Austria: 0660 6386

Call [phone] Mon-Fri 6 amto 10 pm and Saturday 9 am to 4 pm (Mountain Time) free of
charge during the Warranty Period; however, your standard long-distance phone charges still apply.
Please have yourserial number ready when calling.

Post-warrantytelephone assistance is available to answer your product questions. Call (900)
555-1500 ($2.50* per minute, U.S.only), or call [phone] ($25* per call, Visa or MasterCard,
U.S.and Canada) Mon-Fri 7 am to 6 pm and Saturday from 9 am to 3 pm (Mountain Time).Charges
begin only when you connect with a support technician.

*Prices subject to change.

European Customer Support Center Language and In-Country Options Available

(41 22) 780-7111
(54 1) 781-4059/69
[phone]
(55 11) 709-1444
[phone]
(8610) 6261-4174; 6261-4175;
6261-4176;6262-5666
(42 2) 471 7321
(30 1) 689 64 11
800-7729
(36 1) 252 4505
[phone]
(21) 350-3408
(31 20) 581-3318
(82 2) 3270-0700;outside Seoul, call
080-999-0700

Open Monday-Friday 8:30-18:00 CET

Norwegian Norway: 22 11 6299

Danish Denmark: 3929 4099
Finnish Finland: 0203 47288
Swedish Sweden: 08 619 2170
Italian Italy: 02 26410350
Spanish Spain: 902 321 123
Portuguese Portugal: 01 441 7199

In-Country Support Numbers

Malaysia
Mexico D.F.
Mexico Guadalajara
Mexico Monterey
New Zealand
Philippines
Poland
Portugal
Russia
Singapore
Switzerla nd
Taiwan
Thailand
Turkey

[phone]
(52 5) 326-4600
(52 3) 669 95 00
(52 83) 378 42 40
(64 9) 356-6640
(63 2) 894-1451
(48 22) 37-5065
(351 1) 301 7330
(7 095) 923-5001
(65) 272-5300
(41 1) 753 7111
[phone]
[phone];661-4012
(90 1) 224-5925

1

Information

Product

North American Response Center

The North American Response Center (NARC) is available for technical support to
assist service technicians. The NARC can be reached at 1-800-544-9976. To access
this service, HP resellers must have a valid CZ number.

Product Information 1-13

Warranty

This warranty gives you specific legal rights. You may also have other rights, which
may vary from area to area.

Hewlett-Packard warrants the 5L and 6L LaserJet printers against defects in
materials and workmanship for a period of one year from the date of purchase by
the end user and is not transferable.

During the warranty period, Hewlett-Packard will, at its option, either repair or
replace hardware products that prove to be defective.

Should Hewlett-Packard be unable to repair or replace the product within a
reasonable amount of time, a refund of the purchase price may be made upon return
of the product. To have your printer serviced by Hewlett-Packard, you must make
arrangements to have it serviced in the country of purchase.

Warranty Exclusions

The warranty on your HP LaserJet printer shall not apply to defects or damage
resulting from:

• Improper or inadequate maintenance by customer.

• Customer-supplied software or interfacing.

• Unauthorized modification or misuse.

• Operation outside of the environmental specifications for the product.

• Operation of nonsupported printing media.

• Duty cycle abuse (see later explanation).

• Operating the printer from a mechanical switchbox without a designated surge

protector.

• Improper site preparation and maintenance.

• Use of non-HP toner cartridges (see explanation) or DRAM (JEDIA) memory

cards.

The use of non-Hewlett-Packard toner cartridges does not affect either the warranty
or any maintenance contract purchased from Hewlett-Packard. However, if an HP
LaserJet printer failure or printer damage is found to be directly attributable to the
use of any non-HP product, the repair will not be covered under the warranty or HP
maintenance contract. Hewlett-Packard cannot recommend use of non-HP toner
cartridges, either new or remanufactured, because they are not HP products and
Hewlett-Packard cannot influence or control their quality.

Operation of the printer beyond the limit of its duty cycle (printing more than the
equivalent of 4,000 single-sided pages per month on the HP LaserJet 5L or more
than the equivalent of 6,000 single-sided pages per month on the HP LaserJet 6L)
shall be deemed printer abuse and all repairs thereafter will be billed on a time and
materials basis.

1-14 Product Information

If you are using a mechanical switchbox, ensure that it is equipped with a surge
protector. Damage to your printer could occur from the use of unprotected
mechanical switchboxes.

The warranty period begins either on the date of delivery or, where the purchase
price includes installation by Hewlett-Packard, on the date of installation.

Warranty Limitations

The warranty set forth above is exclusive and no other warranty, whether written or
oral, is expressed or implied. Hewlett-Packard specifically disclaims the implied
warranties of merchantability and fitness for a particular purpose.

Some areas do not allow limitations on how long an implied warranty lasts, so the
preceding limitation or exclusion may not apply to you. However, any implied
warranty of merchantability or fitness is limited to the one-year duration of this
written warranty.

In no event will Hewlett-Packard or its suppliers be liable to you for any
consequential or incidental damages, including any lost profits or lost savings, or
for any claim by any party, even if a representative of HP or its suppliers has been
advised of the possibility of such damages.

Some areas, states, or provinces do not allow the exclusion or limitation of
incidental or consequential damages, so the preceding limitation or exclusion may
not apply to you.

1

Information

Product

Note

Voltage Conversions

HP LaserJet printers are manufactured to different specifications for different
countries. Because of these differences, HP does not recommend transporting
products sold within one country to another country.

In addition to the 115-220 voltage environment concerns, the country of final
destination may have different import and export restrictions, power frequencies,
and regulatory requirements.

The HP LaserJet family printers must be serviced by an authorized repair depot or
reseller within the country where the printer was originally purchased.

Because of the different specifications and warranty coverage limitations,
Hewlett-Packard does not offer a conversion, or support the conversion, of HP
LaserJet family printers. We advise those customers planning to transport
equipment to different countries to purchase the products in the country of final
destination.

Product Information 1-15

1-16 Product Information

Site Requirements

Contents

Site Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Operating Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Printer Space Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

The HP C3906A/F Toner Cartridge . . . . . . . . . . . . . . . . . . . . . . . 2-5

Storage Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Storing Opened Toner Cartridges . . . . . . . . . . . . . . . . . . . . . . 2-5

Toner Cartridge Handling Suggestions . . . . . . . . . . . . . . . . . . . . 2-6

2

Site Requirements 2 -1

2 -2 Site Requirements

Site Requirements

Operating Environment

The environmental requirements listed in the table below must be maintained to
ensure the proper operation of this printer.

Table 2-1 Environmental Requirements

LaserJet 5L/6L & Cartridge Operating Storage

Temperature 50 to 90.5° F (10 to 32.5° C) 32 to 104° F (0 to 40° C)

Humidity 20 to 80% RH

(with no condensation)

Consider the following points before installing the printer:

10 to 80% RH
(with no condensation)

• Install in a well-ventilated, dust-free area.

• Install on a hard, flat and continuous surface, with all four printer feet level. Do

not install on carpet or other soft surfaces.

• Ensure adequate power is supplied. Printer power requirements are listed under

“Specifications,” in Chapter 1. Uninterruptible power supplies (UPS) should not be
used with this printer.

• Install away from direct sunlight, open flames, or ammonia fumes. If the printer

is placed near a window, make sure the window has a curtain or blind to block any
direct sunlight.

• Install with enough space around the printer for proper access and ventilation.

(See Figure 2-1.)

2

Site

Requirements

• Install printer away from the direct flow of exhaust from air ventilation systems.

Site Requirements 2 -3

Figure 2-1

Printer Space Requirements

Printer Space Requirements

Table 2-2 Printer Dimensions

Width 13.2 in.(335.5 mm)
Depth 12.3 in.(311.2 mm)
Height (storage)

(operational)
Weight (with toner cartridge) 15.9 lbs.(7.2 kg)
Toner cartridge weight** 1.5 lbs.(.7 kg)

* With letter input assembly extended.
** Some quantity of toner will reside in the waste toner area of a toner cartridge when the toner

supply is exhausted. Therefore, using toner cartridge weight may be an unreliable indication of
remaining toner supply.

2 -4 Site Requirements

Description Dimension

8.9 in.(227.5 mm)

14.6 in.(372.7 mm)*

The HP C3906A/F Toner Cartridge

Toner cartridges contain components that are sensitive to light, temperature, and
humidity. Follow the recommendations in this section to ensure the highest quality
and longest life of HP toner cartridges.

Keep the printer within the following environmental conditions for optimum
performance.

Storage Conditions

The toner cartridge is affected by its environment. Packaging protects the toner
cartridge from light and increases its storage life. It is important to store the
cartridge in its original packaging until the cartridge is ready to be installed in the
printer.

When storing the toner cartridge in a warehouse or work area, make sure the storage
place meets the conditions specified in Table 2-1.

Storing Opened Toner Cartridges

Because the cartridge does not have a shutter to cover the laser beam access slot, it
should be kept inside the printer until empty. Toner cartridges which have had the
toner sealing tape removed are also more vulnerable to environmental extremes
(such as high humidity).

If the toner cartridge must be removed from the printer, always store the cartridge:

• Inside the protective bag in which it was originally packaged.

• In a dark cabinet, away from direct sunlight.

• Correct side up and in a horizontal position (not standing on end).

• At a temperature between 32° to 104° F (0° and 40° C).

• Away from ammonia or other organic solvent fumes.

2

Site

Requirements

Caution

Note The C3906F toner cartridge is designed specifically for use in the environmental

Never ship the printer with a toner cartridge installed. Excessive vibration during
shipping can cause toner to leak, contaminating the printer. Never expose the toner
cartridge to direct sunlight or to room light for more than a few minutes. Bright
light and direct sunlight can permanently damage a toner cartridge.

conditions of the Asia Pacific region and is only available in that region.

Site Requirements 2 -5

Figure 2-2

Toner Cartridge Handling Suggestions

• Before installing a cartridge, distribute the toner evenly by rotating the cartridge

back and forth five to six times. (See Figure 2-2.) Repeat this action when toner
begins to run low.

TonerCartridge C3906A

Toner Cartridge Distribution

• Do not touch the surface of the photosensitive drum in the cartridge. Protect the

drum from light and contamination.

• Do not expose the cartridge to unnecessary vibrations or shock.

• Do not expose the photosensitive drum to strong light. Blurred areas on the page

may indicate that the drum has been exposed to light for too long. This causes
permanent damage to the photosensitive drum. Replace the cartridge.

• Never manually rotate the drum, especially in the reverse directions; internal

damage and toner spills may result.

• Do not install the toner cartridge in the printer for shipping.

2 -6 Site Requirements

Operating Overview

Contents

Using the Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

Control Panel Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

LED Lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

The Front Panel Button . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Printing a Self-Test Page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Continuous Self Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

Printing an Engine Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Resetting the Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11

To Reset the Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11

3

Operating Overview 3-1

3-2 Operating Overview

Using the Control Panel

Control Panel Layout

The Control Panel consists of three status lights and a Front Panel Button located at
the front of the printer.

The Control Panel consists of one button and
three status lights.

ERROR (Yellow)
DA T A (Green)
READY (Green)

These lights can be in only one of the
following states:

OFF ON Blinking

+

+

3

Installation and

Configuration

Operating Overview 3-3

LED Lights

The LED lights provide a quick way to check the printer’s status.

Table 3-1 Indicator Lights (1 of 2)

When this Indicator: Looks like

this:

On
Blinking

On Form Feed There is unprinted

Blinking Manual Feed The printer is in

On Error (light continuously on)

It means this: Do this:

Ready Ready to print.

Print job in progress. Let job finish printing.

data in the buffer.

manual feed mode.

Printer is out of paper.
Printer’sEP door is open.
Toner cartridge is either missing

or not installed correctly.

Briefly press the FrontPanel Button to print the
remaining data.

Make sure youhave the correct paper in the
Single Sheet Input Bin, and briefly press and
release the Front Panel Button to print.

Add paper.
Close the door.
Install a cartridge, being careful to position it

correctly.

3-4 Operating Overview

There is paper jammed in the
printer.

Clear the jam and resume printing.

If the Error light remains lit after checking for
these problems, and there’s no paper jam,
disconnect the power for 10 seconds, then
reconnect to the power source. If, after taking
these actions, the light remains on, refer to
Chapter 7, “Troubleshooting."

Table 3-1 Indicator Lights (Continued 2 of 2)

When this indicator: Looks like

this:

Blinking Error (light blinking) Page Too

All off Sleep Mode Either the printer is

All on Hardware Error There is an

It means this: Dothis:

Complex
The page may be too complex

for the printer’s memory capacity
or the printer may not be able to
create the image fast enough to
keep pace with the engine
printing process.

in SleepMode or the power
source has been disabled.

internal problem that won’t allow
printing.

Briefly press and release the Front Panel Button
to continue printing. There may be some data
loss on the page.

Hint: To avoid this in the future:

1.See your printer driver help for more
suggestions regarding printer memory usage.

2.Reduce resolution to 300 dpi with your
software.

3.Install additional printer memory.(See chapter
6 for information on installing additional memory.)

No action is necessary. When you press the
Front Panel Button, send data to the printer, or
open the printer door, the status light comes on.

1.If you have added an additional memory card,
try removing it.

2.Disconnect the power for 10 seconds, then
reconnect it.

3.If all of the lights come on steadily again, try
disconnecting the power for 15 minutes.

3

Configuration

Installation and

All Blinking Memory Error An incompatible

memory card has been installed.

If this error remains after completing the tasks
above, see Chapter 7,“Troubleshooting."

For memory card specifications, seethe

HP LaserJet 5L User’s Manual,

or the

HP LaserJet 6L User’s Manual,

The memory card must be a 70 nsec or faster
card.

appendix D,

page 1-10.

Operating Overview 3-5

The Front Panel Button

Depending on what state the printer is in, pressing the Front Panel Button allows
you to control printing tasks by either starting or resuming a printer function. Use
the Front Panel Button to accomplish the following tasks:

Table 3-2 Front Panel Button Usage

Function Lights Action Result

Wake Up All lights are off while

SelfTest Ready (bottom) light is on

Printer Reset The Ready (bottom) Light

Resume (from

Manual Feed)
Continue (from

memory error)
Form Feed The Data (middle) Light and

plugged into power source.

and the other lights are off.

will remain lit, if there are no
printer errors.

The Data (middle) Light
blinks.

Error (top) light blinks. Briefly push and release the

the Ready (bottom) Light
both remain on.

Briefly push and release the
button.

Briefly push and release the
button.

Press and hold the button
until the three Front Panel
Lights blink quickly in
succession.

Briefly push and release the
button.

button.
Briefly push and release the

button.

The printer will wake up to a
ready state.

Prints a self-test page.

The reset will return the printer to
the factory default settings.This
clears all data from memory,
including any downloaded fonts
and macros.

Override manual feed to print
from paper cassette.

Allows the printer to recover and
continue printing the job.

The remaining data in printer
memory will print.

3-6 Operating Overview

Figure 3-1

Printing a Self-Test Page

A self-test page can be useful in troubleshooting printer problems and determining
which fonts have been downloaded to the printer.

3

Configuration

Installation and

Self-test Page for HP LaserJet 5L

Operating Overview 3-7

Figure 3-2

1 Make sure the Ready (bottom) Light is on, and all other lights are off. Wake up the

2 Briefly press and release the Front Panel Button. The Data (middle) Light comes

3-8 Operating Overview

Self-test Page for HP LaserJet 6L

The self-test page lists the current printer configuration. (If any fonts have been
downloaded to the printer a second page will print.)

To print a self-test page:

printer if necessary by pressing the Front Panel Button.

on, the Ready (bottom) Light blinks. Wait for a self-test page to print.

Continuous Self Test

A continuous self test can be useful for troubleshooting paper path and other
problems. To print a continuous self test:

1 Disconnect the printer from the power source.
2 Press and hold down the Front Panel Button while connecting power.
3 Continue holding the button for about five seconds.

All lights will illuminate at once, then each will light in sequence.

4 Release the button. The printer conducts its internal diagnostics routine, then prints

the self-test page continuously until stopped.

5 To stop the continuous self test (and reset the printer), press and hold the Front

Panel Button for a few seconds until all lights begin lighting in sequence once again.

Note The self test does not print at the printer’s rated speed of four pages per minute

(HP LaserJet 5L) or six pages per minute (HP LaserJet 6L). The engine test prints at
the printer’s rated speed.

3

Configuration

Installation and

Operating Overview 3-9

Printing an Engine Test

The engine test print can be used to verify that the print engine is functioning
correctly. The Formatter PCA is completely bypassed during an engine test.
Consequently, this test is useful for isolating engine printer problems. The engine
test prints a full page of vertical lines down the entire printable area. This page is
useful for checking and adjusting registration.

Note

Figure 3-3

Perform the engine test with the printer covers in place, as shown in Figure 3-6.
Refer to “Engine Test” in Chapter 7 for the engine test procedure.

Engine Test Button

3-10 Operating Overview

Resetting the Printer

Resetting the printer accomplishes the following:

• Clears all data from the printer’s memory (including unprinted data, downloaded

fonts, and macros).

• Stops any printing that is taking place and ejects the page.

• Removes some error conditions.

• Resets the printer to its factory default settings.

To Reset the Printer

Press and hold the Front Panel Button until the three control panel lights blink
quickly in succession (about 5 seconds), then let go of the button. After resetting,
the Ready (bottom) Light will remain lit if there are no printer errors. (Make sure
there is paper in the printer or the error light will remain on.)

3

Configuration

Installation and

Operating Overview 3-11

3-12 Operating Overview

Printer Maintenance

Contents

Life Expectancy of Consumables . . . . . . . . . . . . . . . . . . . . . . . . 4-3

Toner Cartridge Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Saving Toner with EconoMode . . . . . . . . . . . . . . . . . . . . . . . 4-4

Refilled Toner Cartridges . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

Recycling Toner Cartridges . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

Cleaning the Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

Cleaning Printer Components . . . . . . . . . . . . . . . . . . . . . . . . 4-7

Cleaning Spilled Toner . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8

4

Printer Maintenance 4-1

4-2 Printer Maintenance

Life Expectancy of Consumables

Always inspect the components listed in Table 4-1 for wear when servicing the
printer. Replace these components as needed, based on printer failures or wear, not
strictly on usage.

Table 4-1 Life Expectancy of Consumables

Description HP LaserJet 5L

Toner Cartridge
(user replaceable)

Transfer Roller RF5-1534-000CN RF5-1534-000CN 50,000 May affect print quality

Paper Pickup
Assembly

Separation Pad &
Sub pads

Heating Element

100-120 V,50/60 Hz
220-240 V,50 Hz

Pressure Roller

*

The estimated toner cartridge life is based on Letter or A4 size paper with an average of 5% toner
coverage and a medium density setting. Toner cartridge life can be extended further by conserving
toner using the printer’s EconoMode feature.

Part Number

C3906A C3906A 2,500* When print becomes

RG5-1940-000CN RG5-3486-000CN 50,000 Look for glazing and/or

RY7-5008-000CN RY7-5008-000CN 50,000 May affect paper

RG5-1964-000CN

RG5-1965-000CN
RF5-1516-000CN

HP LaserJet 6L

Part Number

RG5-3459-000CN

RG5-3463-000CN
RF5-2362-000CN

Est Life

(pgs)

50,000 Mayaffect print quality

Remarks

faint, shakecartridge to
distribute remaining
toner.

and/or paper movement.

cracks.

movement.

and/or paper movement.
Look for marks on
pressure roller or upper
Teflon sleeve.

4

Maintenance

Printer Maintenance 4-3

Figure 4-1

Toner Cartridge Life

The toner cartridge has been designed to simplify the replacement of the printer’s
major “consumable” parts. The toner cartridge contains the printing mechanism and
a supply of toner. When using a typical word-processing application, a toner
cartridge will print approximately 2500 pages where the text covers about 5% of the
page.

Five Percent Text Coverage

When regularly printing pages with less coverage, such as short memos, a toner
cartridge should print over 2500 pages. However, if routinely printing very dense
print, the cartridge will not print a full 2500 pages.

Note

For best results, always use a toner cartridge before the expiration date stamped on
the toner cartridge box.

Saving Toner with EconoMode

Toner cartridge life can be extended dramatically by using the EconoMode printing
feature of the printer. EconoMode uses approximately 50% less toner than normal
printing. The printed page is much lighter and is adequate for printing drafts or

4-4 Printer Maintenance

proofs. EconoMode can be set through your printer driver. See Chapter 3 for
information.

Notes

Some software applications may refer to this as “draft mode."

Refilled Toner Cartridges

While Hewlett-Packard does not prohibit the use of refilled toner cartridges during
the warranty period or while under a maintenance contract, we do not recommend
their use. The reasons for this are:

• Hewlett-Packard has no control or process to ensure that a refilled toner cartridge

functions at the high level of reliability of a new HP LaserJet toner cartridge.

• Hewlett-Packard also cannot predict what the long-term reliability effect on the

printer is from using different toner formulations found in refilled cartridges.

• Hewlett-Packard has no control over the actual print quality of a refilled toner

cartridge. The print quality of HP LaserJet toner cartridges influences the
customer’s perception of the printer.

Repairs resulting from the use of refilled toner cartridges are not covered under the
HP warranty or maintenance contract.

Recycling Toner Cartridges

In order to reduce waste, Hewlett-Packard has adopted a recycling program for used
toner cartridges. Plastics and other material are recycled. Cartridge components that
do not wear out are reused. HP pays the shipping costs from the user to the
recycling plant. For each cartridge returned, HP donates one U.S. dollar to be
shared by the Nature Conservancy and the National Wildlife Federation. To join this
recycling effort, follow the instructions inside the toner cartridge box.

4

Maintenance

Printer Maintenance 4-5

Cleaning the Printer

To maintain the print quality, thoroughly clean the printer:

• Every time you change the toner cartridge.

• After printing approximately 2,500 pages.

• Whenever print quality problems occur.

Clean the outside of the printer with a lightly water-dampened cloth. Clean the
inside with only a dry, lint-free cloth. Observe the warnings and cautions below.

WARNING!

Before you begin these steps, unplug the printer to avoid shock hazard.
When cleaning around the front door area, avoid touching the heating element. It

may be HOT. (For heating element location, see Figure 6-14.)

4-6 Printer Maintenance

Cleaning Printer Components

CAUTION

To avoid permanent damage to the toner cartridge, do not use ammonia-based
cleaners on or around the printer. Do not touch the transfer roller with your fingers.
Contaminants on the roller can cause print quality problems.

Table 4-2 Cleaning Printer Components

COMPONENT CLEANING METHOD/NOTES

Outside Covers Use a water-dampened cloth. Do not use solvents or

Inside General Use a dry, lint freecloth. Remove all dust, spilled toner, and

Exit Roller Use a water-dampened lint-free cloth. (For location, see

Fuser Exit Roller Use a water-dampened lint-free cloth. (For location, see

Pickup Roller Use a lint-free cloth dampened with isopropyl alcohol. (For

Pressure Roller Use a dry lint-free cloth. (For location, see Figure 6-16.)
Transfer Roller Use a dry, lint-free cloth. DO NOT TOUCH with your fingers.

Separation Pad Use a dry lint-free cloth. (For location, see Figure 6-31.)
Delivery Assembly Use a water-dampened lint-free cloth. (For location, see

Static Eliminator Teeth Use compressed air.(See Figure 4-2 on the following page

ammonia-based cleaners.

paper particles.

Figure 6-8.)

Figure 6-18.)

location, see Figure 6-25.)

(For location, see Figure 6-30.)

Figure 6-10.)

for static eliminator teeth location.)

Printer Maintenance 4-7

4

Maintenance

Figure 4-2

Static Eliminator Teeth (located in front of the transfer roller)

Note

Cleaning Spilled Toner

Defective toner cartridges can develop leaks. In addition, after a paper jam has
occurred, there may be some toner remaining on the rollers and guides inside the
printer. The pages that print immediately after the jam may pick up this toner.

Clean spilled toner with a cloth slightly dampened in cold water. Do not touch the
Transfer Roller with the damp cloth or with your fingers. Do not use a vacuum
cleaner unless it is equipped with a micro-fine particle filter.

If toner gets on your clothing, use cold water to remove it. Hot water sets toner
stains into fabric.

4-8 Printer Maintenance

Functional Overview

Contents

Basic Printer Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

DC Controller/Power System . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4

Print Engine Control System . . . . . . . . . . . . . . . . . . . . . . . . . 5-5

Power System (on DC Controller PCA) . . . . . . . . . . . . . . . . . . . 5-6

Formatter System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8

CPU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8

Read Only Memory (ROM) . . . . . . . . . . . . . . . . . . . . . . . . . 5-8

Random Access Memory (RAM) . . . . . . . . . . . . . . . . . . . . . . 5-8

Parallel Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8

Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9

Resolution Enhancement (REt) . . . . . . . . . . . . . . . . . . . . . . . . 5-9

EconoMode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10

Memory Enhancement technology (MEt) . . . . . . . . . . . . . . . . . 5-10

Enhanced I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11

Page Protect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11

PJL Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11

Image Formation System . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12

Toner Cartridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-13

Step 1: Drum Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-13

Step 2: Drum Conditioning . . . . . . . . . . . . . . . . . . . . . . . . . 5-13

Step 3: Image Writing . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-13

Step 4: Image Developing . . . . . . . . . . . . . . . . . . . . . . . . . 5-14

Step 5: Image Transferring . . . . . . . . . . . . . . . . . . . . . . . . . 5-14

Step 6: Image Fusing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14

Paper Feed System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-15

Paper Jam Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18

Basic Sequence of Operation . . . . . . . . . . . . . . . . . . . . . . . . . 5-19

5

Functional Overview 5 - 1

5 - 2 Functional Overview

Figure 5-1

Basic Printer Functions

This chapter presents a generalized functional overview of the printer and the
printing processes. The following printer systems are discussed:

• DC Controller System/ Power System

• Formatter System

• Image Formation System

• Paper Feed System

• Laser/Scanner System

Figure 5-1 is a generalized block diagram of the printer:

Printer Functional Block Diagram

Functional Overview 5 - 3

5

Functional

Overview

Figure 5-2

DC Controller/Power System

The DC Controller PCA coordinates all print engine activities, drives the laser, and
coordinates print data from the Formatter PCA with the image formation process.
The DC Controller also includes both AC and DC power supply and distribution
circuitry. The DC Controller controls the following systems and functions:

• Print Engine Control

• Laser and Scanner Drive

• Paper Motion Photosensors (Paper Out, Paper Registration, and Paper Exit

Sensors)

• Motor

• Power System

• AC Power Distribution

• DC Power Distribution

• Overcurrent/Undervoltage Protection

• SleepMode

• High Voltage Power Distribution

Figure 5-2 shows the various DC controller loads.

DC Controller Loads

5 - 4 Functional Overview

AC Driver

Low-Voltage

Supply

+5V
+12V

Print Engine Control System

Laser and Scanner Drive

Based on information received from the Formatter, the DC Controller sends signals
to the Laser/Scanner Assembly to modulate the laser diode ON and OFF and to
drive the Laser/Scanner motor. Refer to “Image Formation System,” later in this
chapter for more information.

Paper Motion Monitoring and Control

The DC Controller PCA controls paper motion by continuously monitoring the
various paper sensors and coordinating the timing with the other print processes.

For a detailed explanation of paper movement, and the interaction of photosensors
and solenoid with the paper movement process, refer to the section “Paper Feed
System,” later in this chapter.

+12 V Shutoff Switch

The 12 volt DC power shutoff switch, Switch 101, located on the top of the printer,
is activated by the printer door. The front door must be closed before the printer can
resume printing.

Engine Test Switch

The Test Print, Switch 201, located on the DC Controller, is activated manually
through an access hole at the front of the printer. This switch causes the print engine
to perform a self-test diagnostic which bypasses the Formatter PCA and prints a full
page of black vertical lines. This test is useful for troubleshooting printer problems
because it isolates the print engine from the Formatter PCA. (See Chapter 7,
“Troubleshooting,” to learn more about how to perform an engine test.)

Motor

The Motor is controlled by the DC Controller PCA. The Motor provides all of the
printer’s paper movement.

Functional Overview 5 - 5

5

Functional

Overview

Power System (on DC Controller PCA)

The AC, DC, and high voltage power supply circuits are all contained within the DC
Controller PCA.

AC Power Distribution

The AC power circuitry supplies AC voltage whenever the power cord is connected
to the AC power source. AC voltage is distributed to the DC power supply circuitry
and to the AC driver circuitry, which controls AC voltage to the fusing assembly’s
heating element.

DC Power Distribution

The DC power distribution circuitry, located on the DC Controller PCA, distributes
+5 V DC and +12 V DC as follows:

+5VDC: Formatter PCA

Photosensors
DC Controller Circuitry

Laser/Beam Detect Circuitry

+12 V DC: Motor

Scanner Motor
Solenoid

+12VA DC: High Voltage Power Supply

Overcurrent/Overvoltage Protection

There are two overvoltage /overcurrent devices in this printer:

• Fuse F101 provides overcurrent protection for the fusing system circuitry. To

check or replace the fuse requires the removal of the DC Controller. Fuse 102
(found only on 110V units) provides overcurrent protection to the printer DC power
supply circuitry.

• In addition, the +12V DC and +5V DC power circuitry contains an overcurrent

protection circuit which automatically shuts off the output voltage when an
overcurrent condition occurs due to a short or abnormal voltage on the load side.

SleepMode

Instead of a power switch, the printer has a SleepMode function. After the printer
has been idle for 15 minutes, it turns itself off by shifting to SleepMode. The front
panel lights remain off, and the printer retains all printer settings and downloaded
fonts and macros while in SleepMode.

5 - 6 Functional Overview

The printer exits SleepMode and all of the lights power on when any of the
following occur:

• A job is received.

• The Front Panel Button is pressed.

• The printer front door is opened.

Note

The printer will not enter SleepMode if there is a printer error.

High Voltage Power Distribution

The High Voltage Power Supply PCA applies an overlap of DC and AC voltage to
the primary charging roller and the developing roller. This circuit also applies a
positive or negative DC voltage to the transfer charging roller according to the
instructions from the CPU on the DC Controller PCA.

This circuit also controls the image density by changing the primary AC voltage and
the developing AC bias according to the setting of the print density dial.

High voltage is disabled when the printer’s EP Door is open (i.e., switch SW101 is
open).

Functional Overview 5 - 7

5

Functional

Overview

Formatter System

The Formatter PCA is responsible for the following:

• Receiving and processing print data from the printer interface.

• Monitoring Front Panel Button and relaying printer status information.

• Developing and coordinating data placement and timing with the print engine.

• Storing font information.

• Communicating with the host computer through the Bi-Directional Interface.

The Formatter PCA receives print data from the Bi-Tronics Interface and converts it
into a dot image. The DC Controller synchronizes the Image Formation System
with the Paper Feed System and signals the Formatter to send the print image data.
The Formatter sends the print image data (dots) in the form of a VIDEO signal and
the printing process begins.

The Formatter PCA also provides mounting locations for additional memory.

CPU

The Formatter PCA incorporates a Motorola 68030 custom-built microprocessor
operating at 24 MHz.

Read Only Memory (ROM)

Besides storing microprocessor control programs, the ROM stores dot patterns of
internal character sets (fonts).

Random Access Memory (RAM)

The RAM stores printing and downloaded font information received from the host
system and temporarily stores a full page of print image data before the data is sent
to the print engine. (See “Page Protect” later in this chapter.) Memory capacity can
be increased by adding a DRAM memory card to the Formatter PCA. Note that
adding memory may also increase print speed when printing complex graphics.

Parallel Interface

The Formatter PCA receives incoming data through its Bi-Tronics interface. The
Bi-Tronics I/O provides high speed and two-way communication between the
printer and the host, allowing the user to change printer settings and monitor printer
status from the host computer. This interface is IEEE-1284 compliant.

5 - 8 Functional Overview

Control Panel

Status LED Lights

The Formatter uses three LEDs mounted under the printer cover to communicate
printer status to the user. Refer to “Using the Control Panel” in Chapter 3 and
“Printer Error Troubleshooting” in Chapter 7 for more information on the lights.

Front Panel Button

The Formatter PCA is connected to a microswitch located on the control panel
PCA. The single button is used for such functions as self test, reset, and to display
error codes. Refer to “Using the Control Panel” in Chapter 3 for more information
on the Front Panel Button.

Resolution Enhancement (REt)

The Formatter PCA contains circuitry for Resolution Enhancement technology
(REt), which modifies the standard video dot data on its way to the DC Controller
to produce “smoothed” black-to-white boundaries. REt is user-adjustable from
some software applications. Available settings are On or Off.

Functional Overview 5 - 9

5

Functional

Overview

Figure 5-3

EconoMode

The EconoMode setting uses approximately 50% less toner than standard mode
printing by reducing the dot density. However, EconoMode does not extend toner
cartridge component life. EconoMode, which can also be thought of as “draft
mode,” is user-selectable through some software applications. The default setting is
Off.

EconoMode vs Normal Mode

Note

EconoMode does not affect print speed or memory usage.

Memory Enhancement technology (MEt)

The Hewlett-Packard Memory Enhancement technology (Met) effectively doubles
the standard memory through a variety of font and data compression methods. MEt
is only available in PCL mode and is not customer selectable. When using the
host-based driver, your PC handles memory management.

5 - 10 Functional Overview

Enhanced I/O

The Enhanced I/O feature allows printer memory to be used for storing data
received from the host computer. When Enhanced I/O is enabled, you can send
more data to your printer in shorter amounts of time, which allows you to return to
your application sooner. Enhanced I/O has the following options:

• Auto—allows the printer to use Enhanced I/O memory allocation to increase the

speed of data transfer from the host computer to the printer, if necessary.

• Off—uses the minimum amount of printer memory for storing data sent from the

host computer.
Enhanced I/O is only available in PCL mode. When using the host-based driver,

your PC handles memory management.

Page Protect

Page complexity (rules, complex graphics, or dense text) may exceed the printer’s
ability to create the page image fast enough to keep pace with the Image Formation
process. If Page Protect is disabled and a page is too complex, the page may print in
parts (for example, the top half on one page and the bottom half on the next page).
Some print data loss is likely in these instances, and the printer will display an error
message.

Page Protect allows the Formatter to create the entire page image in page buffer
memory before physically moving the paper through the printer. This process
ensures that the entire page will be printed. Page Protect applies only to PCL
printing. The default setting is Auto.

PJL Overview

Printer Job Language (PJL) is an integral part of configuration, in addition to the
standard Printer Command Language (PCL). With standard Centronics cabling, PJL
allows the printer to perform functions such as:

• Two-way communication with the host computer through a Bi-directional Parallel

connection. The printer can tell the host such things as the control panel status.

• Isolation of print environment settings from one print job to the next. For

example, if a print job is sent to the printer in landscape mode, the subsequent print
jobs print in landscape only if they are formatted for landscape printing.

Functional Overview 5 - 11

5

Functional

Overview

Figure 5-4

Image Formation System

Laser printing requires the interaction of several different technologies (such as
electronics, optics, and electrophotographics) to provide a printed page. Each
process functions independently and must be coordinated with the other printer
processes. Image formation consists of six processes:

• Step 1. Drum Cleaning

• Step 2. Drum Conditioning

• Step 3. Image Writing

• Step 4. Image Developing

• Step 5. Image Transferring

• Step 6. Image Fusing

Electrostatic Latent Image Formation Block

2. Scanning Exposure

1. Primary Charging

Drum Cleaning

Block

Paper Delivery

7. Drum Cleaning

Fuser Block

5. Separation

6. Fusing

Image Formation Block Diagram

4. Transfer

Transfer Block

3. Developing

Registration

Flow Of Paper
Direction Of Drum Rotation

Developing

Block

Multi-Purpose Tray

Manual Feeding Slot

5 - 12 Functional Overview

Toner Cartridge

As the “heart” of the Image Formation System, the toner cartridge houses the
cleaning, conditioning, and developing steps of the process. The toner cartridge
contains the photosensitive drum, primary charging roller, developing station, toner
cavity, and cleaning station. Including these components, which wear, degrade, or
are consumed in the replaceable toner cartridge, eliminates the need for a service
call when replacement is required. The special photosensitive properties of the drum
allow an image to be formed on the drum surface and then transferred to paper.

CAUTION The printer’s toner cartridge does not include a light-blocking shutter. Be careful to

avoid exposing the drum to light, which can permanently damage the drum. Protect
the cartridge whenever removing it from the printer.

Step 1: Drum Cleaning

The cleaning blade is in contact with the surface of the drum at all times. As the
drum rotates during printing, excess toner wiped off and stored in the waste toner
receptacle.

Step 2: Drum Conditioning

After the drum is physically cleaned, it must be conditioned. This process consists
of applying a uniform negative charge on the surface of the drum with the primary
charging roller, located in the toner cartridge. The primary charging roller is coated
with conductive rubber. An AC bias is applied to the roller to erase any residual
charges from any previous image. In addition, a negative DC bias is applied by the
charging roller to create a uniform negative potential on the drum surface. The
amount of DC voltage is modified by the print density setting.

Step 3: Image Writing

During the writing process, a modulated laser diode projects the beam onto a
rotating scanning mirror. As the mirror rotates, the beam reflects off the mirror, first
through a set of focusing lenses, off a mirror, and finally through a slot in the top of
the toner cartridge, and onto the photosensitive drum. The beam sweeps the drum
from left to right, discharging the negative potential wherever the beam strikes the
surface. This creates a latent electrostatic image, which later is developed into a
visible image.

Because the beam is sweeping the entire length of the drum and the drum is
rotating, the entire surface area of the drum can be covered. At the end of each
sweep, the beam strikes the beam detect lens, generating the Beam Detect Signal
(BD). The BD signal is sent to the DC Controller, where it is converted to an
electrical signal used to synchronize the output of the next scan line of data.

Functional Overview 5 - 13

5

Functional

Overview

Step 4: Image Developing

At this stage of the process, the latent electrostatic image is present on the drum.
The toner particles obtain a negative surface charge by rubbing against the
developing cylinder which is connected to a negative DC supply. The negatively
charged toner is attracted to the discharged (exposed, grounded) areas of the drum,
and repelled from the negatively charged (non-exposed) areas.

Step 5: Image Transferring

During the transferring process, the toner image on the drum surface is transferred
to the paper. A positive charge applied to the back of the paper by the transfer roller
causes the negatively charged toner on the drum surface to be attracted to the paper.
After separation, the drum is cleaned and conditioned for the next image.

Step 6: Image Fusing

During the fusing process, the toner is fused into the paper by heat and pressure to
produce a permanent image. The paper passes between a heated fusing element and
a soft pressure roller. This melts the toner and presses it into the paper.

5 - 14 Functional Overview

Paper Feed System

Both the Paper Input Bin and the Single Sheet Input Slot merge into one, main input
area. Paper placed in either of these areas enables the Paper Out Sensor (sensor

202), which informs the DC Controller that paper is present.
When the printer receives a print job and is ready to print, the DC Controller

enables the Laser/Scanner Assembly and the Motor. Paper motion begins when the
DC Controller energizes solenoid SL1. This causes the paper pick up roller to rotate
once. Two actions occur as a result of this rotation. First, the paper kick plate pushes
the paper against the pick-up roller. Second, the pick-up roller grabs the top sheet
and advances it to the Feed Assembly drive rollers. To ensure that only one sheet is
fed, a main separation pad, along with two subpads, hold the remainder of the stack
in place.

The feed assembly drive rollers advance the paper to the Paper Registration
photosensor (PS203). This sensor informs the DC Controller of the exact location of
the paper’s leading edge, so that the image being written on the photosensitive drum
can be precisely positioned on the page. The feed assembly drive rollers then
advance the paper to the transfer area where the toner image on the photosensitive
drum is transferred to paper.

After the image is transferred, the paper enters the fusing assembly where heat from
the fuser and pressure from the Pressure Roller permanently bond the toner image
to paper. The Paper Exit Sensor (PS201) determines that paper has successfully
moved out of the fusing area. The fusing assembly exit rollers deliver paper to
either the Output Paper Bin or the Front Output slot, depending upon the position of
the Face-up/Face-down lever.

Functional Overview 5 - 15

5

Functional

Overview

Figure 5-5

Figure 5-5 shows a simplified paper path and the locations of the photosensors and
rollers.

Simplified Paper Path

5 - 16 Functional Overview

Figure 5-6

Figure 5-6 shows the locations of the photosensors, switches, solenoid, and other
important printer elements. Table 5-1 describes the function of each photosensor
and the solenoid.

Solenoid and Sensors

Table 5-1 Solenoid and Photosensors

No. Name Description

SL1 Paper Pick-up Solenoid Enables the Paper Pickup Roller.
PS201 Paper Exit Sensor Senses when paper has successfully moved out of the

PS202 Paper Out Sensor Senses no paper in either the Paper Input Bin or Manual

PS203 Paper Registration Sensor Detectsthe leading and trailing edges of the paper.

PS204 Door Open/Cartridge Sensor (HP LaserJet 5L only)

In the HP LaserJet 6L, SW101 performs the
functions of 5L’s PS204.

fusing area and the next sheet of paper can be fed.

Input Slot.If this sensor does not sense paper in the Input
Paper Bin or the Single-Sheet Input Slot, the formatter
displays the paper-out indication on the front panel. Paper
must be reloaded before printing can resume.

Synchronizes the photosensitive drum and the top of the
paper.

Detects whether printer door is open and cartridge is in
place.If the door is open or the cartridge is not in place, the
control panel LEDs will display an error message.Printing
cannot continue until the door is closed and the cartridge is
in proper position.

Functional Overview 5 - 17

5

Functional

Overview

Paper Jam Detection

The Paper Out Sensor (PS202), Paper Registration Sensor (PS203), and the Paper
Exit Sensor (PS201) detect when paper is moving through the printer. (See Figure
5-5 for roller and sensor locations.) If a paper jam is detected, the DC Controller
immediately stops the printing process and causes a paper jam indication on the
front panel.

A paper jam can be detected under any of the following conditions:

• Power-On Jams. Paper is present under either PS201 or PS203 at power-on.

• Pickup Jams. Paper does not reach and clear photosensor PS203 within a specified

period of time. The time period begins when the Paper Pickup Solenoid (SL1) is
energized.

• Delay Jams. Paper does not reach or clear a specific photosensor within a specified

period of time.

5 - 18 Functional Overview

Basic Sequence of Operation

The Formatter PCA and the DC Controller PCA share information during printer
operation. The DC Controller-to-Formatter Connector (J201) forms a link which
operates as a serial data bus. This allows printer status, command information, and
dot-image data to be passed between the two PCAs. Figure 5-7 shows the general
timing of the printer events. The following events take place during normal printer
operation:

Table 5-2

Period Timing Purpose

WAIT From when the paper is inserted to the end of Main

STBY (standby) Fromthe end of the WAIT or the LSTR period until

INTR (initial
rotation)

PRNT From the end of initial rotation until the Scanner

LSTR (last
rotation)

Motor initial rotation.

the input of the PRNT signal from the Formatter.Or
from the end of the LSTR period until power OFF.

From the input of the PRNT signal from the
Formatter until the laser diode intensity has been
stabilized.

Motor stops.

From the primary voltage (DC) OFF until the Main
Motor stops.

If another PRNT signal is sent from the Formatter,
the printer returns to the INTR period. If not, it
returns to the STBY period.

Printer Timing

Clear the drum surface potential and clean the
Transfer Roller.

Maintain the printer in ready state.

Stabilize the photosensitive drum sensitivity in
preparation for printing. Also clean the Transfer
Roller.

Form images on the photosensitive drum based on
the /VDO signal from the Formatter and transfer the
image to paper.

Deliver the last sheet of paper.Also clean the
Transfer Roller.

Refer to Timing Diagram on the next page

Functional Overview 5 - 19

5

Functional

Overview

Figure 5-7

General Timing Diagram - HP LaserJet 5L

5 - 20 Functional Overview

Figure 5-8

General Timing Diagram - HP LaserJet 6L

Functional Overview 5 - 21

5

Functional

Overview

5 - 22 Functional Overview

Removal and Replacement

Contents

Removal and Replacement Strategy . . . . . . . . . . . . . . . . . . . . . . . 6-3

Required Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4

Installing Memory Cards (DRAM) . . . . . . . . . . . . . . . . . . . . . . . 6-5

Covers and Doors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6

Back Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6

EP Door Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8

Memory Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9

Main Cover and Paper Input Assembly . . . . . . . . . . . . . . . . . . 6-10

Internal Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11

Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11

Exit Roller Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-12

DeliveryAssembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13

Fuser Pressure Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-15

Heating Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17

Pressure Roller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-20

Face-Up/Face-Down Lever . . . . . . . . . . . . . . . . . . . . . . . . . 6-21

Fuser Exit Roller Assembly . . . . . . . . . . . . . . . . . . . . . . . . 6-22

Paper Exit Sensor Flag . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-23

Top Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24

Laser/Scanner Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24

Solenoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-25

Pickup Roller Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 6-27

Paper Feed Frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-30

Transfer Roller Guide & Transfer Roller . . . . . . . . . . . . . . . . . . 6-34

Kick Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-35

Separation Pad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-37

Subpads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-38

Feed Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-39

Bottom Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-42

Memory Door Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-42

Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-43

DC Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-44

Formatter Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47

6

Removal and Replacement 6 - 1

6 - 2 Removal and Replacement

Removal and Replacement Strategy

This chapter documents removal and replacement of Field Replaceable Units
(FRUs) only. Exchange assemblies should be sent to SMO for repair.

Replacement is generally the reverse of removal. Occasionally, notes are included to
provide direction for difficult or critical replacement procedures.

6

Removal and

Replacement

WARNING!

Caution

Note

Unplug the power cord from the power outlet before attempting to service the
printer. If this warning is not followed, severe injury may result.

Never operate or service the printer with the protective cover removed from the
Laser/Scanner Assembly. The reflected beam, although invisible, can damage your
eyes.

The sheet metal edges of this printer can be sharp! Exercise caution when working
with the printer.

The printer contains parts that are electrostatic discharge (ESD) sensitive. Always
service printers at an ESD-protected workstation.

To install a self-tapping screw, first turn it counter-clockwise to align it with the
existing thread pattern, then carefully turn clockwise to tighten. Do not overtighten.
If a self-tapping screw-hole becomes stripped, repair the screw-hole or replace the
affected assembly.

Always remove the toner cartridge before removing or replacing parts.

Removal and Replacement 6 - 3

Required Tools

• #2 Phillips screwdriver with a magnetic tip

• 5.5 mm hexhead nutdriver

• small flathead screwdriver

• needlenose pliers

Caution

Figure 6-1

A Posidriv screwdriver will damage the printer’s screw heads. Use Phillips only.

Figure 6-1 shows the difference between a Phillips and a Posidriv screwdriver. Note
that a Phillips tip has more beveled surfaces.

Phillips and Posidriv screwdrivers

6 - 4 Removal and Replacement

Installing Memory Cards (DRAM)

1 Unplug the power cord from the printer. You

should not install a memory card while the
printer is in SleepMode.

2 Open the Printer Door, remove the toner

cartridge, and close the Printer Door. Protect
the toner cartridge from light while you are
working on the printer.

3 Remove any paper in the paper tray. Gently

tip the printer onto its side so that the memory
cover is on top as shown in Figure 3.

4 Remove the Memory Expansion Cover by

carefully pulling the tab out and away from
the printer in a gentle rocking motion.

5 Align the memory card with the corner notch

so it is positioned as in Figure 4. Push it firmly
into the printer.

Replace the Memory Expansion Cover, set the
printer upright, reinstall the toner cartridge,
reinsert paper, and reconnect to the power source.

6

Removal and

Replacement

Print a self-test page (see Chapter 3) to check that
the printer recognizes the additional memory you
have added. Your Total Memory in the “Printer
Information” section will show the new MB total.

1 MByte card 2 MByte total
2 MByte card 3 MByte total
4 MByte card 5 MByte total
8 MByte card 9 MByte total

Removal and Replacement 6 - 5

Covers and Doors

Back Cover

1 Unplug the power cord and remove the parallel cable from the back of the printer.
2 Remove the toner cartridge.
3 Lift the Input Extender assembly.

Caution You must lift the Input Extender when the covers are removed or it will break. After

you have removed the covers, leave the Input Extender in this lifted position for
ease of replacement.

4 Remove the (3) screws (Figure 6-2, callout 1).

Figure 6-2

Back Cover Removal (1 of 2)

6 - 6 Removal and Replacement

Figure 6-3

5 Separate the rear panel from the main cover, pulling the lower corners away from

the printer first. Then, insert the small flathead screwdriver into the openings at the
top to pop the upper corners (Figure 6-3, callout 1).

6 Remove the cover by grabbing it on both sides and pulling it straight back with a

firm pull (Figure 6-3, callout 2).

6

Removal and

Replacement

Back Cover Removal (2 of 2)

To reinstall

Make certain the Input Extender is up.

Removal and Replacement 6 - 7

Figure 6-4

EP Door Assembly

1 Unplug the power cord and remove the parallel cable from the back of the printer.
2 Open the EP door.
3 Remove the toner cartridge.
4 Along the door hinge, there is a flex point. Firmly press the left tab inward to

release it. The right tab will fall out easily (Figure 6-4).

EP Door Assembly Removal

6 - 8 Removal and Replacement

Figure 6-5

Memory Door

1 Unplug the power cord and remove the parallel cable from the back of the printer.
2 Remove the toner cartridge.
3 Gently tip the printer onto its side so that the Control Panel is on top.
4 Carefully pull the door tab out (Figure 6-5, callout 1) and away from the printer in a

gentle rocking motion (Figure 6-5, callout 2).

6

Removal and

Replacement

Memory Door Removal

Removal and Replacement 6 - 9

Main Cover and Paper Input Assembly

1 Remove the toner cartridge.
2 Remove memory door.

Caution

Figure 6-6

Remove the memory door first. The door will break if you remove the Main Cover
without removing the memory door.

3 Remove the EP Door Assembly.
4 Remove the Back Cover.
5 Remove the (2) screws from the top of the printer (Figure 6-6, callout 1).
6 Grasp the two lower, front corners of the printer and pull gently outward to release

the front of the Main Cover.

7 Lift the cover straight off.
8 Remove the Paper Input Assembly (Figure 6-6, callout 2) by rotating it forward and

lifting it out with firm pressure.

Main Cover and Paper Input Assembly Removal

Note

When replacing the Paper Input Assembly, make certain that the mylar sheet is
positioned between the Input Feed Roller and Separation Pad and that the sheet is
not folded or bent.

6 - 10 Removal and Replacement

Figure 6-7

InternalAssemblies

Control Panel

1 Remove the Printer Covers.
2 Use the needlenose pliers to release the Control Panel connector (Figure 6-7,

callout 1).

3 Press the tab on the top of the Control Panel downward (Figure 6-7, callout 2).

The Control Panel will pop out of the printer chassis.

4 Lift the Control Panel out.

6

Removal and

Replacement

Control Panel Removal

Removal and Replacement 6 - 11

Figure 6-8

Exit Roller Assembly

1 Remove Printer Covers.
2 Grasp both tabs at the lower ends of the Exit Roller bushings and pull inward. This

will release the tabs from the printer chassis (Figure 6-8, callout 1).

3 Rotate the tabs 90 degrees, clear of the printer chassis (Figure 6-8, callout 2).
4 Lift the roller out.

Exit Roller Removal

To reinstall

The end of the Exit Roller that has a gear attached must fit into the gear train. It is
possible to reinstall the Exit Roller so that the gear end is on the opposite side of the
printer; this placement would cause paper path problems.

6 - 12 Removal and Replacement

DeliveryAssembly

1 Remove the Printer Covers and Exit Roller Assembly.
2 Remove the EP Right-Hand assembly by pressing the tab in (Figure 6-9, callout 1)

and sliding the assembly toward the front of the printer (Figure 6-9, callout 2).

6

Removal and

Replacement

Note

Figure 6-9

The EP Right-Hand assembly must be removed to access any fuser components.

Delivery Assembly Removal (1 of 2)

Removal and Replacement 6 - 13

Figure 6-10

3 Use the magnetic screwdriver to remove the (2) screws (Figure 6-10, callout 1).

Once the screws have been removed, rotate the rear of the Delivery Assembly up
and forward and lift it out of the printer.

Note

Delivery Assembly Removal (2 of 2)

Upon reinstallation, the tabs on the front end of the Delivery Assembly must fit
under the sheet metal fuser plate below to correctly reseat the Delivery Assembly.

6 - 14 Removal and Replacement

Figure 6-11

Fuser Pressure Plate

1 Remove Printer Covers and Delivery Assembly (Figures 6-9 and 6-10).
2 Remove the (2) screws (Figure 6-11, callout 1).
3 Press the Fuser Plate retainer clips out to release the Pressure Plate (Figure 6-11,

callout 2).

4 Rotate the plate around and toward the back and lift up to remove it (Figure 6-11,

callout 3).

6

Removal and

Replacement

Fuser Pressure Plate Removal

Removal and Replacement 6 - 15

Figure 6-12

To reinstall:

The Fuser Pressure Plate is kept in place by four locking mechanisms in each
corner. Place the rear slits in the plate over the rear brackets that hold the Fusing
Assembly (Figure 6-12, callout 1). Lower the plate over the retaining clips, pressing
on both sides of the Fuser Pressure Plate (Figure 6-12, callout, 2). It is important
that the spring is placed over the positioning pin (callout 3) because inadequate
pressure will cause fusing problems. Replace the screws.

Fuser Pressure Plate Replacement

6 - 16 Removal and Replacement

Figure 6-13

Heating Element

1 Remove Printer Covers, Delivery Assembly (Figures 6-9 and 6-10), and Fuser

Pressure Plate (Figure 6-11).

2 Remove the wire cover (on the right side of the printer) for the Heating Element

wires by pressing in on the tab and pulling outward (Figure 6-13, callout 1).

6

Removal and

Replacement

Heating Element Removal (1 of 3)

Removal and Replacement 6 - 17

Figure 6-14

3 Disconnect the AC voltage to the Heating Element by releasing the connector

located on the DC Controller. Press down on the connector release with a small,
flathead screwdriver (Figure 6-14, callout 1). (Since this is a small space, it is much
easier to reach the connector with a screwdriver.) Pull straight out (Figure 6-14,
callout 2).

Heating Element Removal (2 of 3)

6 - 18 Removal and Replacement

Figure 6-15

4 Remove the wire from the wire guides along the right-side of the printer.
5 Disconnect the thermistor feedback connector in the left front side of the Fusing

Assembly (Figure 6-15).

Heating Element Removal (3 of 3)

6

Removal and

Replacement

6 Lift the Heating Element out.

To reinstall

Make sure the connectors are properly reattached.

Removal and Replacement 6 - 19

Figure 6-16

Pressure Roller

1 Remove Printer Covers, Delivery Assembly (Figures 6-9 and 6-10), Fuser Pressure

Plate (Figure 6-11), and Heating Element (Figures 6-13 through 6-15).

2 Remove the Pressure Roller guide by lifting the edge (Figure 6-16, callout 1) and

then rolling it gently backward (Figure 6-16, callout 2).

Pressure Roller Guide Removal

3 Lift the right end of the Pressure Roller up and out of the printer chassis.

Note

Note

The right end of the Pressure Roller is greased.

4 The left side will follow easily with the Pressure Roller gear still attached.

When reinstalling the Pressure Roller, apply a drop of grease to the grounding plate
on the right side of the shaft. (Refer to Chapter 8 for a part number.)

6 - 20 Removal and Replacement

Face-Up/Face-Down Lever

1 Remove Printer Covers, Delivery Assembly (Figures 6-9 and 6-10), Fuser Pressure

Plate (Figure 6-11), and Heating Element (Figures 6-13 through 6-15), and Pressure
Roller (Figure 6-16).

2 Rotate the lever forward 90 degrees (past the spring) and pull it straight out the front

of the printer.

To reinstall

1 Make sure the lever arm is on the left and is initially pointing downward.
2 Pull the spring forward using needlenose pliers.
3 Slide the short, round tabs into the grooves on the Separation Guide Assembly. The

machined ridges on the lever will face you.

4 Release the spring so it falls in place in front of the square tab (Figure 6-17).

6

Removal and

Replacement

Note

Figure 6-17

While the shape of the lever was changed for the HP LaserJet 6L (a stiffening rod
was also added), these procedures for Face-Up/Face-Down Lever removal remain
unchanged. Figure 6-17 shows the lever from an HP LaserJet 5L.

Face-Up/Face-Down Lever Replacement

Note

You can tell when the lever is in place because there are two plastic grooves that fit
precisely in front of the Exit Rollers, and you should be able to feel the spring’s
release mechanism.

Removal and Replacement 6 - 21

Fuser Exit Roller Assembly

1 Remove Printer Covers, Delivery Assembly (Figures 6-9 and 6-10), Fuser Pressure

Plate (Figure 6-11), and Heating Element (Figures 6-13 through 6-15), Pressure
Roller (Figure 6-16), and Face-Up/Face-Down Lever (Figure 6-17).

2 Remove the gear from the left end of the roller shaft by pressing down on the

catching mechanism with the small flathead screwdriver and pulling the gear away.

3 Remove the Exit Roller Assembly by pressing the small, white tab upward (Figure

6-18, callout 1) and rotating it around (Figure 6-18, callout 2).

Note While the shape of the white tab was changed for the HP LaserJet 6L, these

procedures for Fuser Exit Roller Assembly removal remain unchanged. Figure 6-18
shows the white tab from an HP LaserJet 5L.

4 Slide the Exit Roller Assembly forward and out to the right of the printer.

Figure 6-18

Fuser Exit Roller Removal

6 - 22 Removal and Replacement

Paper Exit Sensor Flag

1 Remove the Printer Covers, Delivery Assembly (Figures 6-9 and 6-10), and Fuser

Pressure Plate (Figure 6-11).

6

Removal and

Replacement

Caution

Note

Figure 6-19

Before proceeding to Step 2, examine the Paper Exit Sensor flag. It is important to
note the position of the spring mechanism on the flag. The spring must be
reinstalled to exactly this position.

2 Remove the Paper Exit Sensor flag by pressing down on the left side and pulling up

on the right side.

To reinstall

It is important that you reinstall the flag correctly, because installing it incorrectly
will cause the Control Panel to display an error with the Paper Exit Sensor (PS201).

Place the left side of the flag in the correct position first, then slide the right side
into place, making certain the spring is on top of the flag (Figure 6-19). If the spring
exerts no pressure on the flag, it may require “respringing” by giving the spring an
extra turn before reinstalling. The flag should fit snugly in place.

Paper Exit Sensor Flag Replacement

Removal and Replacement 6 - 23

TopAssemblies

Laser/Scanner Assembly

1 Remove the Printer Covers.
2 Remove both Laser/Scanner connectors (Figure 6-20, callout 1).
3 Remove all (4) screws and lift the assembly straight off (Figure 6-20, callout 2).

Note

Figure 6-20

One of the four screws is longer than the other three. Upon reinstallation, the longer
screw must be replaced in its original location.

Laser/Scanner Assembly Removal

6 - 24 Removal and Replacement

Figure 6-21

Solenoid

1 Remove the Printer Covers.
2 On the left side of the printer, remove the paper pickup gear (Figure 6-21, callout 1)

by pressing the tabs in the center of the gear outward and pulling the gear off
(Figure 6-21).

6

Removal and

Replacement

Solenoid Removal (1 of 2)

Removal and Replacement 6 - 25

Figure 6-22

3 Remove the Solenoid connector (J204) from the DC Controller (Figure 6-22,

callout 1).

4 Remove the self-tapping screw that holds the Solenoid in place (Figure 6-22, callout

2).

5 Unthread the wires from the printer chassis.
6 Lift the Solenoid off.

Solenoid Removal (2 of 2)

Note

When reinstalling this part, the Paper Pickup Gear is keyed to go on the shaft in
only one way.

6 - 26 Removal and Replacement

Pickup Roller Assembly

1 Remove the Printer Covers.
2 Remove the paper pickup gear (Figure 6-21).

6

Removal and

Replacement

Note

Figure 6-23

This gear is keyed to go on the shaft in only one way.

3 Remove the pickup roller grounding clip on the right of the printer by lifting each

end of the clip up and over the two metal guides and sliding the clip off. Figure 6-23
depicts the clip from an HP LaserJet 5L. The clip from an HP LaserJet 6L (and
some HP LaserJet 5Ls) is shaped differently.

Pickup Roller Assembly Removal (1 of 2)

Removal and Replacement 6 - 27