HP LaserJet 5L and 6L Printer (C3941/C3990) Service Manual
Hewlett Packard Co.
Printed in USA 9/97
HP LaserJet 5L and 6L Printer
HP LaserJet 5L
HP LaserJet 6L
© Copyright Hewlett-Packard
Company 1997All Rights Reserved.
Reproduction, adaptation, or
translation without prior
written permission is
prohibited, except as allowed
under the copyright laws.
First edition, May 1997
11311 Chinden Boulevard
Boise, Idaho 83714
The information contained in
this document is subject to
change without notice.
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
Electrical Shock HazardTo avoid electrical shock, use
only supplied power cords and
connect only to properly
grounded (3-hole) wall outlets.
This manual uses the following conventions:
Color is used to emphasize items which are important to the material under
The names of major printer parts and assemblies are CAPITALIZED.
Bold is used for emphasis, particularly in situations whereitalic type would be
Italic type is used to indicate related documents or emphasis.
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.
1 Product InformationOrientation 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.
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
Allparts 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.
Use the subject index to quickly locate any information in the manual.
List of Figures