Canon LBP-CX Series User manual

SERVICE
MANUAL
REVISION 2
Canon
JULY 1985 RYB-8301-020
COPYRIGHT BY CANON INC. CANON LBP-CX SERIES REV.2 JULY 1985 PRINTED IN JAPAN (IMPRIME AU JAPONJ

Copyright © by Canon Inc.
1985
Printedin Japan
lmprime au Jap_on
Use of this manual should be
strictly supervised
to avoid dis-
closure
of confidential infor-
mation.
Prepared by
REPROGRAPHIC PRODUCTS QUALITY ASSURANCE DIVISION
CANON INC.
7-1 Nishi-Shinjuku 2-chome, Shinjuku-ku, Tokyo 160, Japan
COPYRIGHT © BY CANON INC. CANON LBP-CX SERIES REY.2 JULY 1985 PRINTED IN JAPAN (IMPHIME AU JAPONJ

INTRODUCTION
This service manual contains basic information required for after-sale service of laser beam printers (240
raster lines/inch and 300 raster lines/inch models). This information is vital to the serviceman in maintaining high
printing quality and performance
of the printer. The content of this manual may be revised as a result of product
modification. There revisions are detailed in Service Information Bulletins.
Chapter
1: General Description
Features, specifications, operation, and parts
of the printer
Chapter
2: Operation and Timing
A brief description
of the different systems in the printer and their roles in producing a print
Chapter 3: The Electrical System
Printer timing and signals, explanation of selected circuit
Chapter 4: The Mechanical System
Explanation
of mechanical operation, disassembly, reassembly, and adjustment
Chapter 5: Installation
Requirements for a suitable location and installation procedures
Chapter 6: Maintenance and Servicing
Parts replacement schedule, expected service lives of printer parts, and details of periodic servicing
Chapter 7: Troubleshooting
What
to do if the printer malfunctions
Chapter 8: Appendix
COPYRIGHT © BY CANON INC. CANON LBP-CX SERIES REY.2 JULY 1985 PRINTED IN JAPAN (IMPRIME AU JAPON)
III

TABLE OF CONTENTS
CHAPTER 1 GENERAL DESCRIPTION
I. FEATURES .................. 1- 1 IV. PARTS OF THE PRINTER
..... 1- 4
II. SPECIFICATIONS
............. 1- 2
V. OPERATION ................. 1- 6
III. SAFETY INFORMATION
...... 1- 3
CHAPTER 2 OPERATION AND TIMING
I. BASIC OPERATION ........... 2- 1 III. PRINT UNIT ................. 2- 6
II. LASER/SCANNER
............ 2- 4 IV. SYSTEM INTERFACE ......... 2-17
CHAPTER 3 THE ELECTRICAL SYSTEM
I. OUTLINE OF THE ELECTRICAL
SYSTEM .................... 3- 1
II. REFERENCE LISTS
........... 3- 2
Ill. PRINT PROCESS ............. 3-14
IV. LASER/SCANNER ............ 3-21
V. CIRCUIT DIAGRAMS
BY FUNCTION ............... 3-24
VI.
POWER SUPPLIES ............ 3-51
VII. TIMING CHART FOR
DC
CONTROLLER INPUTS/
OUTPUTS
................... 3-54
CHAPTER 4 THE MECHANICAL SYSTEM
I. EXTERNALS ................. 4- 1
II. DRIVE SYSTEM
.............. 4- 6
III. PAPER TRANSPORT
SYSTEM .................... 4- 7
IV. EXPOSURE SYSTEM .......... 4-15
V. ELECTROSTATIC IMAGE/
DEVELOPING/CLEANING
SYSTEM .................... 4-17
VI. FIXING
SYSTEM ............. 4-20
VII. ELECTRICAL COMPONENTS
... 4-25
CHAPTER 5 INSTALLATION
I. INSTALLATION III. STORING
AND HANDLING EP
SUGGESTIONS ............... 5- 1 CARTRIDGES
................ 5- 7
II. UNPACKING
AND
INSTALLATION .............. 5- 2
CHAPTER 6 MAINTENANCE AND SERVICING
I. EXPECTED SERVICE LIFE OF IV. SERVICE CHECKPOINTS ...... 6- 5
CONSUMABLES ... , .......... 6- 1
V. CUSTOMER MAINTENANCE ... 6- 7
II.
UST OF TOOLS ............. 6- 2
III. LIST OF LUBRICANTS,
CLEANERS
.................. 6- 4
COPYRIGHT © BY CAllOll INC. CAllON LBP-CX SERIES REY.2 JULY 1985 PRINTED Ill JAPAN (IMPRIME AU JAPOll)
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CHAPTER 7 TROUBLESHOOTING
I. INTRODUCTION
A. Initial Check .................. 7- 1
B. Basic Procedure ............... 7- 1
H. CHECK/ADJUSTMENT
A. Printer Driver and Laser Driver
Checker Operation ............. 7- 2
B. Image Adjustment
1. Basic image adjustment
......... 7- 3
2. Adjusting the height of the transfer
corona wire
.................. 7- 3
C. Mechanical Adjustment
1. Adjusting the cassette spring
lifting force
.................. 7- 3
2. Adjusting the fixing rollers
(nip width)
................... 7- 3
D. Electrical Adjustment
1. LEDs and VR settings
.......... 7- 5
2. Checking the DC controller and AC
driver (AC controller and the fixing
roller heater safety circuits)
...... 7- 5
3. Adjusting laser power ........... 7- 7
lli. IMAGE DEFECTS
A. Examples oflmage Defects ...... 7-13
B. How to Read the Troubleshooting
Tables
....................... 7-14
C. Troubleshooting Image Defects
I-1. Light image
................ 7-15
I-2. Dark image
................. 7-16
I-3. Blank
print ....•............ 7-17
1-4. Black image ................ 7-18
I-5. Stained separation strip
....... 7-18
I-6. Stains
on back of paper ....... 7-19
I- 7. Dark vertical lines
(paper feed direction)
......... 7-19
I-8. Sharp horizontal black lines (cross
feed direction)
.............. 7-20
I-9. Vertical fogged stripes
(paper feed direction)
......... 7-20
I-10. Horizontal fogged stripes
(cross feed direction)
......... 7-20
I-11. White horizontal lines or other
shapes on a black print
........ 7-21
I-12. Thin vertical white lines
or stripes
(paper feed direction)
......... 7-21
1-13. Faulty registration ........... 7-22
I-14. Poor fixing
................. 7-22
I-15. Distortion
.................. 7-23
I-16. Waviness
................... 7-23
IV. TROUBLESHOOTING
MALFUNCTIONS
M-1. There is no power ............ 7-24
M-2. The main
motor does not
rotate ..................... 7-27
M-3. The high-voltage power supply does
not provide power ........... 7-27
M-4. The fixing roller heater does
not
operate .................... 7-28
M-5. Cannot feed paper manually
.... 7-29
M-6. Paper
is not fed from
the cassette
................. 7-30
M-7. Jam are detected when there are
no jams
.................... 7-31
M-8. Jams are
not detected ......... 7-31
M-9. The PAPER OUT indicator lights
when there
is still paper ....... 7-32
M-10. The PAPER OUT indicator does
not light when there is no
paper
..................... 7-32
M-11. The preconditioning exposure lamps
do
not light ................ 7-34
M-12. Laser, scanner malfunction
..... 7-34
M-13. Heater malfunction
.......... 7-35
M-14. All LEDs on the display panel
do
not light ................ 7-36
M-15. The READY/WAIT indicator does
not stop flashing ............. 7-37
M-16. The READY/WAIT indicator does
not light ................... 7-37
M-17. Printing does
not start when a TRUE
print command (PRNT)
is input .... ' ................ 7-37
V. PAPER TRANSPORT PROBLEMS
(A jam occurs every time paper is fed.)
A. Paper Jams
T-1. Manual feed unit
..... ~ ...... 7-39
T-2. Cassette pickup assembly ...... 7-39
T-3. Separation/feeder
unit ........ 7-39
T-4. Fixing/delivery area
.......... 7-40
B. Incomplete Feed
T-1. Sheets stuck together
......... 7-40
T-2. Wrinkles ................... 7-40
VI
COPYRIGHT © BY CANON INC. CANON LBP·CX SERIES REV.2 JULY 1985 PRINTED IN JAPAN (IMPRIME AU JAPONI

APPENDIX
l LOCATIONS OF ASSEMBLIES,
UNITS ...................... A-1
II. GENERAL CIRCUIT
DIAGRAM . . . . . . . . . . . . . . . . . . . A-3
HI. WIRING DIAGRAM . . . . . . . . . . . A-5
IV. DC CONTROLLER
A. DC Controller Circuit Diagram . . . . A- 7
B. DC ControllerPCB: Connector
Locations and Signals ........... A-10
V. HIGH-VOLTAGE POWER SUPPLY
CIRCUIT DIAGRAM
........... A-11
VI. DC POWER SUPPLY AND MAIN
MOTOR DRIVER CIRCUIT
DIAGRAM ................... A-12
VII. AC DRIVERCIRCUIT DIAGRAM
(AC CONTROLLER AND
FIXING
ROLLER HEATER SAFETY
CIRCUIT) ................... A-12
VIII. VARISTOR AND PRECONDITIONING
EXPOSURE LAMPS AND PRINT
COUNTER CIRCUIT
. DIAGRAMS .................. A-13
IX. EXPANSION RAM CIRCUIT
DIAGRAM ................... A-14
X. DCCONTROLLERPCB
LAYOUT .................... A-15
XI. DC POWER SUPPLY & MAIN
MOTOR DRIVER PCB
LAYOUT
.................... A-16
XII.
AC DRIVER PCB LAYOUT
(AC CONTROLLER PCB,
FIXING ROLLER HEATER
SAFETY PCB) ................ A-17
xm. VARISTOR PCB LAYOUTS ..... A-18
XIV. PRECONDITIONING EXPOSURE
LAMPS AND PRINT COUNTER
PCB LAYOUT ................ A-18
XV. EXPANSION
RAM PCB
LAYOUT .................... A-19
XVI.LABELS
..................... A-23
COPYRIGHT © BY CANON INC. CANON LBP-CX SERIES REY.2 JULY 1985 PRINTED IN JAPAN (IMPRIME AU JAPOHJ
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