Tektronix Phaser 840 User manual

Warning
The following servicing instructions are for
use by qualified service personnel only. To
avoid personal injury, do not perform any
servicing other than that contained in
operating instructions unless you are qualified
to do so.
This printing: May 1998
071-0388-00
PHASER® 840
COLOR LASER PRINTER
Service Quick Reference Guide

Copyright © 1998 by Tektronix, Inc., Wilsonville, Oregon. Printed in the United
States of America. All rights reserved. Contents of this publication may not be
reproduced in any form without permission of Tektronix, Inc.
Tektronix
®
, Phaser
®
, and Made for Each Other
®
are registered trademarks of
Tektronix, Inc. TekColor™, PhaserShare™, PhaserMatch™, PhaserLink™,
Finepoint™ and PhaserPrint™ are trademarks of Tektronix, Inc.
RealSUPPORT
SM
and TekColor Care
SM
are service marks of Tektronix, Inc.
Other marks are trademarks or registered trademarks of the companies with
which they are associated.
November 1998. First printing
December 1998. Changed pages: 41, 60, 76, 84, 85, 108, 126, 133
May 1999. Changed pages: 5, 61, 62, 68, 74, 112, 118, 124, 126, 127, 147, 149
TE/mq/mm

User safety summary
Terms in manual
CAUTION Conditions that can result in damage to the product.
WARNING Conditions that can result in personal injury or loss of life.
Power source: For 110 VAC printers, Do not apply more than 130 volts RMS
between the supply conductors or between either supply conductor and ground.
Use only the specified power cord and connector. For 220 VAC printers, do not
apply more than 250 volts RMS between the supply conductors or between either
supply conductor and ground. Use only the specified power cord and connector.
Refer to a qualified service technician for changes to the cord or connector.
Operation of product: Avoid electric shock by contacting a qualified service
technician to replace fuses inside the product. Do not operate without the covers
and panels properly installed. Do not operate in an atmosphere of explosive
gases.
WARNING Turning the power off using the On/Off switch does not de-
energize the printer. You must remove the power cord to
disconnect the printer from the mains. Keep the power cord
accessible for removal in case of an emergency.
Safety instructions: Read all installation instructions carefully before you plug the
product into a power source.
Terms on product
CAUTION A personal injury hazard exists that may not be apparent.
For example, a panel may cover the hazardous area. Also
applies to a hazard to property including the product itself.
DANGER A personal injury hazard exists in the area where you see the
sign.
Care of product: Disconnect the power plug by pulling the plug, not the cord.
Disconnect the power plug if the power cord or plug is frayed or otherwise
damaged, if you spill anything into the case, if product is exposed to any excess
moisture, if product is dropped or damaged, if you suspect that the product needs
servicing or repair, and whenever you clean the product.
Ground the product: Plug the three-wire power cord (with grounding prong) into
grounded AC outlets only. If necessary, contact a licensed electrician to install a
properly grounded outlet.

Symbols as marked on product:
DANGER high voltage:
Protective ground (earth) terminal:
Use caution. Refer to the manual(s) for information:
WARNING: If the product loses the ground connection, usage of knobs and
controls (and other conductive parts) can cause an electrical shock. Electrical
product may be hazardous if misused.
Service safety summary
For qualified service personnel only: Refer also to the preceding Users Safety
Summary.
Do not service alone: Do not perform internal service or adjustment of this product
unless another person capable of rendering first aid or resuscitation is present.
Use care when servicing with power on: Dangerous voltages may exist at several
points in this product. To avoid personal injury, do not touch exposed
connections and components while power is on.
Disconnect power before removing the power supply shield, soldering, or
replacing components.
Do not wear jewelry: Remove jewelry prior to servicing. Rings, necklaces, and
other metallic objects could come into contact with dangerous voltages and
currents.
Power source: This product is intended to operate from a power source that will
not apply more than 250 volts rms between the supply conductors or between
either supply conductor and ground. A protective ground connection by way of
the grounding conductor in the power cord is essential for safe operation.
!

Service Guide v
Contents
General Information 1
Phaser 840 printer overview 2
Solid inks 3
About RAM upgrades 3
Memory considerations 4
Print engine assemblies 6
The main board 14
Combination sensors and their meanings 15
Media tray type sensing 15
Front panel 16
Rear panel 18
Regulatory specifications 24
Error Codes and Messages 25
Rear panel LEDs error codes 25
Error messages 28
Troubleshooting 37
System power-up sequence 37
Verifying main board CPU operation 39
Verifying print engine operation by printing its startup page 39
Verifying power supply operation 39
Measuring power supply voltages 40
Inspecting the power supply fuses 40
Testing for shorted drivers 41
Testing for a shorted motor 42
Testing motor and solenoid resistances 42
Media jams and the paper path 43
Media-based problems 43
Paper-pick errors 43
Print transfer jams 44
Checking the process motor and drive train 45
Media skews passing through the paper path 45
Printing and print quality problems 46
Streaks or lines across the print 46
Streaks or lines down the print 46
Missing ink or light colored ink band running length of print 47
Scratches parallel to the long axis of printing, particularly with film 48
White portion of print is colored 48
Color is uneven 49
Not printing 49

vi Phaser 840 Color Printer
Printing too light or too dark 49
Fuzzy text 50
Poor primary color fills 50
Poor small text resolution 51
Ghosting 51
Variation of density on second side of print 52
Ghost of first side image on second side of print 52
Vertical line appear wavy 52
Oil streaks on print 53
Poor ink adhesion, poor image durability 53
Incomplete image transfer to paper 54
Ink smears of first side of duplex print 55
Repeating print defects on print 55
Banding parallel to long edge of print 56
Wrinkling 56
Image is offset or cut off 57
Oil streaks on top of print 57
Macintosh printing problems 57
Image never prints 57
Image prints in black-and-white 58
Image is rotated 90 degrees 58
Printer isn’t in the Chooser 58
Windows printing problems 58
Image never prints 58
Adjustments 59
Bypass mode (manufacturing mode) 59
Cool down mode 59
Hidden service menu 60
Bypassing a “short menu” 60
Printing service test prints 61
Printing the Configuration Page 61
Selecting Duplex Oil Chase 61
Adjustments 62
Process belt tension adjustment 62
Exit roller drive belt tension adjustment 63
Y-axis belts tension adjustment 64
Printhead-to-drum spacing adjustment 66
Cap/wipe/purge assembly belt adjustments 68
Drum position encoder gap 70
Transfix roller pressure spring adjustment 72
X-axis scale adjustment 74
Vacuum check 75

Service Guide vii
Cleaning and Maintenance 77
Cleaning 78
Cleaning Page 79
Vacuum 79
Drum temperature sensor 79
Maintenance 80
Maintenance roller 80
Waste tray 80
Lubrication 81
Inspection 82
Resetting NVRAM 83
Resetting NVRAM 83
Key FRU Removal and Replacement 87
Main board 88
Power supply 89
Power control board 90
Paper/drum heater 91
Upper feed roller assembly 92
Drum/transfix assembly 94
Drum position sensor assembly 99
Printhead 101
X-axis motor and drive assembly 104
Y-axis belt drive assembly 105
Cap/wipe/purge assembly 106
Locking the printhead 108
FRU List 109
High-capacity Paper Tray Assembly 126
Service tools 128
Supplies and accessories 128
Test Prints 133
Wiring Diagrams 145

viii Phaser 840 Color Printer
Figures
The Phaser 840 printer (shown with optional
High-capacity Paper Tray Assembly) 1
Internal features of the print engine 6
Circuit boards of the print engine (right front view) 7
Circuit boards of the print engine (left-rear view) 8
The printer’s I
2
C bus 9
Printhead maintenance system of the print engine 10
Sensors and switches on the right side of the print engine 11
Sensors and switches on the left side of the printer 12
Solenoids and clutches on the print engine 13
Features of the main board 14
Printer front panel 17
Printer rear panel 19
Attaching the service load connector to J250 41
Setting process belt tension 62
Setting exit roller drive belt tension 63
Setting the Y-axis belt tension 65
Attaching the digital gap indicator 66
Spacing the printhead to the drum 67
Aligning (timing) the cap/wipe/purge assembly drive belts 69
Setting the drum position encoder gap 71
Adjusting the transfix roller pressure springs 73
Adjusting the x-axis scale adjustment 74
Connecting the vacuum gauge to the printer 75
Resetting print engine NVRAM menu item 84
Clearing PostScript NVRAM menu item 85
Removing the main board 88
Removing the power supply 89
Removing the power control board 90
Removing the paper/drum heater 91
Remove the upper feed roller assembly (left side) 92
Removing the upper feed roller assembly (front) 93
Removing the drum transfix assembly (left side) 95
Removing the drum/transfix assembly (right side) 97
Marking the drum home flag sensor alignment 99
Removing the drum position sensor assembly 100
Plugging the reservoir holes 101
Removing the printhead 103
Removing the x-axis motor and drive assembly 104

Service Guide ix
Removing the Y-axis belt drive assembly 105
Removing the cap/wipe/purge assembly 107
Cabinet FRUs 111
Imaging FRUs 113
Paper path FRUs 115
Motors and fans FRUs 117
Circuit boards FRUs 119
Solenoids and clutches FRUs 121
Gears and belts FRUs 123
Sensors and flags FRUs 125
High-capacity Paper Tray 127
Print engine wiring diagram 145
Wire routing on the right side of the printer near right I/O board 146
Wire dressing above the x-axis drive 147
Vacuum hose dressing 148
Routing wiring on the left side of the printer 149
Wire dressing behind the printhead 150

x Phaser 840 Color Printer
Tables
Installed RAM and printer capabilities 4
Tray switch sensor combinations 15
Rear panel DIP switch settings 19
Physical dimensions 20
Printer installation clearances 20
Functional specifications 21
Electrical specifications 22
Environmental specifications 23
Main board power-up self-test error codes 25
Front panel and fault history log error codes and messages 28
Motor and solenoid resistances 42
Hidden Service Menu 60
Cabinet FRUs 110
Imaging FRUs 112
Paper path FRUs 114
Motors and fans FRUs 116
Circuit board FRUs 118
Solenoid and clutches FRUs 120
Gears and belts FRUs 122
Sensors and flags FRUs 124
High-capacity Paper tray FRUs 126
Service tools 128
Supplies and accessories 128