Tektronix Phaser 780 Service Manual

PHASER® 780 COLOR LASER PRINTER

Service Quick Reference Guide

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: September 1999 063-3041-01

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

and TekColor CareSM are service marks of Tektronix, Inc.

Other marks are trademarks or registered trademarks of the companies with which they are associated.

October 1998: First Printing

December 1998: Changed pages; 2, 3, 15, 72, 78, 92, 93, 105, 108, 109, 111, 113, 114, 115, 117, 121, 124, 127, 129, 134, 137, 138, 139, 140, 141, 144, 145

TE/mq/mm

Users safety summary

Terms in manual:

Power source:

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:

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.

Safety instructions:

product into a power source.

Terms on product:

CAUTION Conditions that can result in damage to the product. WARNING Conditions that can result in personal injury

or loss of life.

For 110 VAC printers, Do not apply more than 130 volts RMS

Avoid electric shock by contacting a qualiﬁed service

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.

Read all installation instructions carefully before you plug the

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 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 pr oduct needs servicing or repair, and whenever you clean the product.

Ground the product:

grounded AC outlets only. If necessary, contact a licensed electrician to install a properly grounded outlet.

Disconnect the power plug by pulling the plug, not the cord.

Plug the three-wire power cord (with grounding prong) into

Symbols as marked on product:

DANGER high voltage:

Protective ground (earth) terminal:

Use caution. Refer to the manual(s) for information:

Laser use caution. Refer to the manual(s) for information:

WARNING:

controls (and other conductive parts) can cause an electrical shock. Electrical product may be hazardous if misused.

If the product loses the ground connection, usage of knobs and

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.

This product is certiﬁed under IEC 825 as a Class 1 Laser Product.

DANGER:

Invisible laser radiation when open and interlock defeated. AVOID DIRECT EXPOSURE TO BEAM.

PELIGRO:

Cuando se abre y se invalida el bloqueo, se producen radiaciones invisibles de láser. EVITESE LA

EXPOSICION DIRECTA A TALES RAYOS.

CAUTION:

Invisible laser radiation when open and interlocks defeated. AVOID DIRECT EXPOSURE TO BEAM.

VARNING:

Osynlig laserstrálning när denna del är öppnad och spärrar är urkopplade. STRÅLEN ÄR FARLIG.

VORSICHT:

Unsichtbare Laserstrahlung, wenn Abdeckung geöffnet und Sicherheitsverriegelung überbrückt. NICH DEM STRAHL AUSSETZEN.

VAROI:

Näkymätön avattaessa ja suojalukitus ohitettaessa olet alttiina lasersäteilylle. ÄLÄ KATSO SÄTEESEN.

ATTENTION:

Rayonnement laser invisible dangereux en cas d'ouverture et lorsque la sécurité est neutralisée. EXPOSITION DANGEREUSE AU FAISCEAU.

VARNING:

Osynlig laserstrálning när denna del är öppnad och spärrar är urkopplade. BETRAKTA EJ STRÅLEN.

ADVARSEL:

Usynlig laserstràling ved abning når sikkerhedsafbrydere er ude af funktion. UNDGÅ UD ÆTTELSE FOR STRÅLING.

Class 3B

ADVARSEL:

Usynlig laserstraling nar deksel åpnes og sikkerhedslas brytes. UNNGÅ EKSPONERING FOR STRÅLEN.

PJQT4521ZA

9008-78

Contents

General Information 1

Phaser 780 overview 2 Memory considerations 3

Print engine assemblies 5 The image processor 10

Front panel 11 Rear panel 12

Network card LEDs 12

Specifications 14

Regulatory specifications 17

Safety 17 EMC 17 Energy Star certification 17

Error Codes and Messages 19

Troubleshooting 39

System power-up sequence 39 Print engine troubleshooting 40

Printer will not power up 40 Erratic printer operation 41 Making a print engine only test print 42 Printing and print quality problems 43

Initial checks and actions 43 Light (undertone) prints 44 Blank prints 45 Monochrome prints 46 Black prints 47 One color is faded 47 Missing band in direction of paper travel 48 Missing bands in parallel to the leading edge 49 Streaks in direction of paper travel 51 Streaks parallel with the leading edge 52 Banding 53 Edge of print is wrinkled with an area of ragged discoloration. 53 Random missing spots 54 Random spotting 55 Repetitive mark appears on each print 56 Residual image or ghosting 56 Background contamination 57 Unfused image or image easily rubs off of page 58 Toner on back of print 58

Service Guide

vii

Print is mottled 59 Image mis-registered on paper 60 Color layer not correctly registered 60 Color representation not correct 61 Oil stain or gloss variation on print 61 Random spotting 62

Media jams and the paper path 63

Skewed image 63 Damaged prints 64 Inoperative lower tray feeder 65 Power problems 65

All front panel indicators remain off. The printer does not initialize upon power-up 65

Front panel indications 66

Media tray indicates missing or empty when it is not 66

Macintosh printing problems 66

Image never prints 66 Image prints in black-and-white 66 Image is rotated 90 degrees 67

Windows printing problems 67

Image never prints 67 Blue color on the screen is printing too purple. 67 Printing from Windows 3.1 produces the message “Problem writing

device LPT1: Cancel or Retry”. 68

Workstation printing problems 68

Image never prints 68

Running built-in diagnostics 69

Adjustments 73

Printing test prints 73

Print service test prints 73 Printing the configuration page 73 Printing the demonstration pages 73

Print engine calibration 74

Adjusting for impulse banding 74

Cleaning and Maintenance 77

Service preventive maintenance procedure 77

Recommended tools 77

Cleaning 78

Resetting NVRAM 79

viii

Phaser 780 Color Printer

Key FRU Disassembly 81

Paper feeder 82 Feeder registration chute 83 Feeder registration clutch 84 Registration brake clutch 85 Feeder metal registration roller 86 Feeder rubber registration roller 87 Feeder pre-registration clutch 88 Feeder pre-registration rollers 89 Paper-pick turn roller 91 Paper feed drive gear train 92 Paper-feed motor 93 Multi-purpose tray roller assembly 94 Multi-purpose tray pick rollers 95 Auto-density calibration sensor 97 Developer assembly 99 Developer clutch 101 Developer tie plate 102 Toner/developer dispense motor 104 Carousel assembly 105 Carousel motor 107 Carousel motor board 108 Carousel sensor 109 Laser unit 110 Erase lamp rail assembly 112 Erase lamp 114 Process drive unit 115 Waste auger assembly 117 Accumulator belt assembly 119 Accumulator belt cleaner assembly 121 Second bias transfer roller assembly 122 Second bias transfer roller cam assembly 123 Fuser assembly 125 Fuser drive gear train 126 Lower exit assembly 128 Full stack sensor 130 Low voltage power supply 131 High voltage power supply 132 Image processor 133 Image processor chassis 134 Print engine control board 135

Service Guide

FRU List 137

Supplies and accessories 176

Test Prints 179

Wiring Diagrams 185

Phaser 780 Color Printer

Figures

The Phaser 780 printer (shown with optional Lower Tray Assembly) 1 Internal features of the print engine 5 Circuit boards of the print engine 6 Motors of the print engine 7 Sensors and switches on the print engine 8 Solenoids and clutches on the print engine 9 Features of the image processor board 10 Printer front panel 11 Printer rear panel with the optional Ethernet card 13 Adjusting for impulse banding 75 Removing the paper feeder 82 Removing the registration chute 83 Removing the registration clutch 84 Removing the registration brake clutch 85 Removing the metal registration roller 86 Removing the rubber registration roller 87 Removing the feeder pre-registration clutch 88 Removing the feeder pre-registration roller 90 Removing the paper-pick turn roller 91 Removing the paper-feed drive gear train 92 Removing the paper-feed motor 93 Removing the multi-purpose tray roller assembly 94 Removing the multi-purpose tray pick rollers 96 Removing the auto-density calibration sensor 98 Removing a developer assembly 100 Removing the developer clutch 101 Removing the developer tie plate 103 Removing the toner/developer dispense motor 104 Removing the carousel assembly 106 Removing the carousel motor 107 Removing the carousel motor board 108 Removing the carousel sensor 109 Removing the laser unit 111 Removing the erase lamp rail assembly 113 Removing the erase lamp 114 Removing the process drive unit 116 Removing the waste auger assembly 118 Removing the accumulator belt assembly 120 Removing the accumulator belt cleaner assembly 121 Removing the second bias transfer roller assembly 122

Service Guide

Removing the second bias transfer roller cam assembly 124 Removing the fuser assembly 125 Removing the fuser-drive gear train 127 Removing the lower exit assembly 129 Removing the stack full sensor 130 Removing the low voltage power supply 131 Removing the high voltage power supply 132 Removing the image processor 133 Removing the image processor chassis 134 Removing the print engine control board 135 Printer cabinet FRUs 138 Paper feeder FRUs 140 Multi-purpose tray cover FRUs 142 Multi-purpose tray FRUs 144 Paper feeder cover FRUs 146 Paper feeder FRUs 148 Imaging FRUs 150 Developer FRUs 152 Carousel FRUs 154 Accumulator belt assembly FRUs 156 Fuser assembly FRUs 158 Paper exit FRUs 160 Paper exit FRUs 162 Drive FRUs 164 Electronic (rear) FRUs 166 Electronics (front) FRUs 168 Image processor FRUs 170 Optional lower feeder cabinet FRUs 172 Optional Feeder FRUs 174 Print engine wiring diagram 185 Map 1 – Wiring routing at the top and front of the printer 193 Map 2 – Wire routing around the engine control board 194 Map 3 – Wiring routing around the image processor board 195 Map 4 – Wiring routing around the paper feeder 196 Map 5 – Wire routing around the laser scanner and high voltage power supply 197 Map 6 – Wire routing at the rear of the printer 198 Map 7 – Wire routing around the power supply 199 Map 8 – Wire routing around the fuser 200 Wiring 1 – Low voltage power supply, laser unit, and interlock switches 201 Wiring 2 – Engine control board, auto-density calibration sensor, erase lamp, waste

toner sensor 202 Wiring 3 – Low voltage power supply, engine control board, high-voltage power

supply and imaging components 203

xii

Phaser 780 Color Printer

Wiring 4 – Engine control board, used cartridge sensor, cartridge sensor, carousel sensor, developer clutch, developer fan, toner dispense motor 204

Wiring 5 – Engine control board, low voltage power supply, carousel motor board, rotary motor 205

Wiring 6 – Engine control board, low voltage power supply, bias transfer roller cam solenoid accumulator belt sensor, paper feeder motor, process motor 206

Wiring 7 – Engine control board, low voltage power supply, fuser, oil roll assembly 207

Wiring 8 – Engine control board, fuser assembly, environment sensor 208 Wiring 9 – Engine control board, paper size switch board, feed solenoid, no paper

sensor, low paper sensor 209 Wiring 10 – Engine control board, paper feeder 210 Wiring 11 – Engine control board, paper feeder, multi-purpose tray 211 Wiring 12 – Engine control board, top exit sensor, media exit switch, full stack sensor,

fuser fan 212 Wiring 13 – Engine control board, image processor board, front panel, image processor

fan 213 Wiring 14 – Lower Tray Assembly master wiring diagram 214 Wiring 15 – Engine control board and low voltage power supply to Lower Tray

Assembly feeder board 215 Wiring 16 – Lower Tray Assembly feeder board to feeder chute switch, size switches

and feeder motor 216 Wiring 17 – Lower Tray Assembly feeder board to no paper sensors and low paper

sensors 217 Wiring 18 – Lower Tray Assembly feeder board to feed solenoids and turn chutes 218

Service Guide

xiii

Tables

Memory and features sets 3 Physical dimensions of printer 14 Physical dimensions of lower tray feeder 14 Printer clearances 14 Functional specifications 15 Electrical specifications 16 Environmental specifications 16 Diagnostic tests 69 Printer cover FRUs 139 Paper feeder FRUs 141 Multi-purpose tray cover FRUs 143 Multi-purpose tray FRUs 145 Paper feeder cover FRUs 147 Paper feeder FRUs 149 Imaging FRUs 151 Developer FRUs 153 Carousel FRUs 155 Accumulator belt assembly FRUs 157 Fuser assembly FRUs 159 Paper exit FRUs 161 Paper exit FRUs 163 Drive FRUs 165 Electronic (rear) FRUs 167 Electronic (front) FRUs 169 Image processor FRUs 171 Optional lower feeder cabinet FRUs 173 Optional feeder FRUs 175 Supplies and accessories 176 Plug/Jack Locations - 1 186 Plug/Jack Locations - 2 187 Plug/Jack Locations - 3 188 Plug/Jack Locations - 4 189 Plug/Jack Locations - 5 190 Plug/Jack Locations - 6 191 Plug/Jack Locations - 7 192

xiv

Phaser 780 Color Printer

General Information

This service guide contains information useful to verify operation, troubleshoot, repair, adjust, and maintain a Tektronix Phaser® 780 Color Printer.

To ensure complete understanding of the product, we recommend participation in Phaser 780 service training, if available.

The Phaser 780 printer (shown with optional Lower Tray Assembly)

Service Guide

3041-01

Phaser 780 overview

The Phaser 780 Color Printer combines a color laser, continuous-tone print engine with an image processor supporting Adobe’s PostScript 3 page description language. The image processor features a bi-directional parallel interface and a 10baseT Ethernet port for host communication. Optional network adapter cards to the image processor allow the printer to communicate on networks using LocalTalk, Ethernet 100baseT or Token Ring protocols. The Ethernet network card supports EtherTalk 100baseT, Novell and TCP/IP. With the Token Ring network card, the printer supports Token Ring protocols. The network cards are sometimes referred to as “smart cards” because each houses its own processor for executing speciﬁc on-board protocols; only data is transferred from the installed smart card to the printer’s image processor board. The PCL printer language is also supported.

The printer is marketed in three versions:

Phaser 780 N

The printer contains 136 standard, built-in fonts. The standard Phaser 780 prints at a resolution of 600 x 600 dots-per-inch on A and B-size media. The base printer does not support grayscale printing.

Phaser 780 GN

The 600 x 1200 dpi. It also contains 136 fonts. The graphics printers supports 16 level grayscale printing as well as printing oversize-B images.

Phaser 780 P

The features as the GN printer. In addition, the Plus version Phaser 780 supports image pipelining for greater throughput, a print collation mode, and a “check print before proceeding with job” mode. The plus printer also feature a SCSIcompatible interface to connect to an external hard disk drive for additional font storage. The hard disk drive is also required for print collation of multiple copy multi-page prints. A scanner can also be connected to the Plus printer’s SCSI port to give the printer the ability to optically copy color images.

RAM memory in the printers can be supplemented with one or two additional 32, 64-, or 128-Mbyte RAM DIMMs; the maximum usable capacity is 192 Mbytes

Print speeds depend on the chosen resolution and selected media. For r esolutions of 600 x 600 (standard), in color, the printer prints at 4 A-size pages per minute (ppm) on paper . Monochrome printing (Fast Monochr ome) is at 16 ppm on paper . Transparency ﬁlm printing is always 2 ppm.

The printers support printing on A-, A4-, A5-, B-, B4, B5, SRA3, A3-, 13 x 19 in. and Legal-sized paper from a 250-sheet tray. An optional three-tray second feeder (called the Lower Tray Assembly) is available with additional 250-sheet standard media trays. The printer features a built-in multi-purpose tray from which specialty media, cardstock and envelopes can be fed. The printer also supports manual feeding using the multi-purpose tray.

(Standard) comes standard with 64 Mbytes of RAM. The

(Graphics) features 96 Mbytes of RAM and can print at

(Plus) features 192 Mbytes of RAM and supports the same

After being idle for the selected amount of time the printer switches into its Energy Star mode where it consumes less than 45 watts of power. It “awakens” upon receiving data at any of its ports.

Phaser 780 Color Printer

Memory considerations

The base printer features 32 Mbytes of RAM in one connector and features two additional DIMM connectors which accept 16-, 32-, 64-, or 128 Mbytes RAM DIMMs. The printer can use any off-the-shelf RAM meeting these speciﬁcations:

■

168 pin DIMM

■

Synchronous DRAM

■

3.3 volt

■

9 nsec speed

■

Valid on-board Serial Presence Detect ROM.

Upon power-up, the image processor interrogates the 256 byte Serial Presence Detect ROM which describes the DIMM in great detail, with details such as data width, clock delay, number of address columns and row, refresh rate and more. If the DIMM does not meet the required speciﬁcations it will be ignored; no error message will be reported.

With more memory the printer gains the capabilities of printing at higher resolutions, printing without having to use image compression (which trades off less installed RAM for longer image processing time) and dual frame buffers for printing one image while processing a second image (which gives greater printing throughput). With additional RAM memory, the printer’s capabilities increase as detailed in the following table:

Table 1 Memory and features sets

Conﬁguration/ options “Standard”

600 x 600 with full image area

600 x 1200 with full image area

Check Print/ PhaserMatch No No Yes Job Pipelining No No Yes - 2 pages Parallel port buffer 256 kbytes 256 kbytes 512 kbytes Print Collation - requires

hard drive option Fonts available 136 136 136

printer w/ 64 Mbyte RAM

Yes Yes Yes

No Yes Yes

No No Yes

“Graphics” printer w/ 96 Mbyte RAM

“Plus” printer w/ 192 Mbyte RAM

Service Guide

Print the Conﬁguration Page and check the item “installed RAM” to see what type of RAM is installed.

For example: Installed RAM: 96 Mbytes

Mem slot 1: SDRAM/parity/64 MB/KMM366S824AT Mem slot 1: empty

This is a list of DRAM SIMMs that are branded for use by Tektronix at the time this guide was published:

Size 16 Mbyte Samsung KMM366S203BT 32 Mbyte Samsung KMM366S403BT 64 Mbyte Samsung KMM366S824AT 128 Mbyte Samsung KMM366S1623AT 32 Mbyte Smart Module SM564043574N6AA 64 Mbyte Smart Module SM564088574N6AA 32 Mbyte NEC MC-454AD645F-A10B 64 Mbyte NEC MC-454CB645FA-A10B 128 Mbyte NEC MC-4516CD645FZ-A10B 16 Mbyte Micron Tech. MT8LSDT264AG-66CL2 32 Mbyte Micron Tech. MT16LSDT264AG-10BC4 32 Mbyte Micron Tech. MT16LSDT264AG-662C1 64 Mbyte Micron Tech. MT8LSDT864AG-662D3 64 Mbyte Micron Tech. MT8LSDT864AG-10BD2 128 Mbyte Micron Tech. MT16LSDT1664AG-662DT

Maker Part Number

Phaser 780 Color Printer

Print engine assemblies

Carousel assembly

Fuser

Media tray 1

Accumulator belt cleaner

Developer assemblies

Second bias transfer roller

Laser unit

Accumulator belt assembly

Paper feeder

Multi-purpose tray

Imaging unit

3041-02

Internal features of the print engine

Service Guide

Image processor board

Engine control board

Carousel motor board

Network card

Circuit boards of the print engine

Phaser 780 Color Printer

High Voltage board

Low Voltage Power Supply (LVPS)

3041-04

Image processor fan

Process drive assembly

Toner dispense motor

Developer fan

Fuser fan

Paper feed drive gear train

Process motor

Motors of the print engine

Paper feed motor

Carousel motor

Service Guide

3041-03

Exit

ensor

Used toner

artridge ensor

Full stack sensor

Left front cover switch

Toner cartridge presence sensor

user

emperature

ensor

Auto-density calibration sensor

Exit door sensor

Top cover switch

Carousel sensor

Right front cover switch

Waste cartridge full sensor

Waste cartridge sensor

Accumulator belt home sensor

Paper size sensor

Edge sensor

Fuser exit

ensor

Environment sensor

Registration sensor

Sensors and switches on the print engine

Phaser 780 Color Printer

Multi-purpose tray paper present sensor

Long paper sensor

Low paper sensor

Paper empty sensor

3041-05

Registration clutch

Second bias transfer roller solenoid

Developer clutch

Registration brake clutch

Multi-purpose tray clutch

Pre-Registration clutch

Multi-purpose pick-up solenoid

3041-06

Solenoids and clutches on the print engine

Service Guide

The image processor

Real Time Clock / NVRAM

RAM DIMMS

Boot ROM

Features of the image processor board

Font DIMM

SCSI riser card

NVRAM

Network card

Postscript code ROM DIMM

3041-07

Phaser 780 Color Printer

Front panel

These front panel features are found on the printer:

■

A two-line, 40-character LCD

■

Six push buttons

■

Five LEDs

LCD.

The LCD serves two purposes: Displaying current image processor and print engine status information and displaying an interactive menu. Status information includes image processor status such as

Printing Jam

. Print engine status includes messages such as

, and

Toner Low

Ready, Processing

Out of paper, Paper

The interactive menu can only be entered while the printer is idle and r eady. The interactive menu has two modes, review and modify. Customers can review and modify certain NVRAM, I/O ports and peripheral parameters.

and

Buttons.

Button 6, the left-most button, is an

Exit key used to cancel an operation

while in the interactive menu. The functions of the remainder of the buttons are deﬁned by the particular menu or function being displayed on the LCD. The bottom row of the LCD labels the current function of each button.

Ready Print Menu Select

3041-18

Printer front panel

Service Guide

Rear panel

Connectors

The rear panel of the printer features the host interface connectors:

■

Bi-directional parallel (high-density connector).

■

Twisted Pair 10baseT Ethernet connector. RX indicator (green); while the network card is receiving data. The LED is data is being received. If the LED is

on steady

, then a problem (probably

off steady

hardware) has occurred at the network hub.

■

SCSI high-density connector (external hard disk drive or optical scanner only).

With the addition of a network card, the printer can feature either of these groups of connectors:

■

ThinNet (100base2) and Twisted Pair (100baseT) Ethernet connectors. This is Option P1.

■

LocalTalk connector. This is Option P3.

■

Unshielded Twisted Pair (10baseT) and shielded Twisted Pair (DB-9) Token Ring connectors. This is Option P4.

Network card LEDs

blinks

while no

The Ethernet network card has four LED indicators:

■

TX indicator (yellow); blinks while data is transmitted to the host. The LED is off while no data is being sent.

■

Twisted Pair (100baseT) and ThinNet (100base2). RX indicator (green);

blinks

while the network card is receiving data. The LED is

while no data is being received. If the LED is

on steady

off steady

, then a problem

(probably hardware) has occurred at the network hub.

■

TP Link. On steady indicates good circuit to nearest port; off indicates no circuit.

■

100 MBS. Ethernet speed is 100 MBS when lit.

Note

Do not use both Ethernet connectors at the same time. With a Ethernet or Token Ring network card installed, the 10baseT port is disabled.

Phaser 780 Color Printer

The Token Ring network card has two LED indicators:

■

Connection (yellow);

blinks

Ring, Ring,

■

Ring Speed (green); (MBPS),

■

When both LEDs blink, a network card failure has occurred.

while the printer is attempting to insert itself into the Token

when the printer is properly inserted in the ring.

when the card is set for 16 MBPS.

off

when the printer is not inserted into the Token

off

when the card is set for 4 megabits-per-second

The following ﬁgure illustrates the rear panel of the printer.

SCSI port Parallel port 10 base T ethernet port

Slot for network card & IDE hard drive

INS

10Base2

LocalTalk®

Mbs

UTP

10/100Base-TX

100

Mbs

LINK

Series B

Ethernet Card

PhaserShare

Ethernet card

Series B

PhaserShare

LocalTalk Card

LocalTalk card

Printer rear panel with the optional Ethernet card

STP

Series B

PhaserShare

Token Ring Card

Token Ring card

Service Guide

Internal hard drive

3041-08

Speciﬁcations

Table 1 Physical dimensions of printer

Dimension Value

Height 49.2 cm (19 in) without lower tray feeder

Width 69.1 cm (27.2 in) Depth 64.1 cm (24.2 in) Weight 73.6 kg (161 lbs) with consumables installed

90.6 (36 in) with lower tray feeder

97.1 kg (213 lbs) with lower tray feeder and consumables

Table 2 Physical dimensions of lower tray feeder

Dimension Value

Height 41.4 cm (16.3 in) Width 56 cm (22 in) Depth 56 cm (22 in) Weight 23.5 kg (52 lbs)

Table 3 Printer clearances

Dimension Value

Top 40.0 cm (15.7 in) Left 50.3 cm (20 in) Right 55.1 cm (21.5 in) Front 83.5 cm (33 in) Rear Bottom No obstructions underneath that could block cooling vents Mounting surface ﬂatness Front feet less than 5 mm above or below rear feet

Mounting surface dimensions

Phaser 780 Color Printer

15.0 cm (6 in)

Left feet less than 10 mm above or below right feet

Level surface with dimensions of at least 79 cm (31 in.) by 152 cm (60 in.).

Table 4 Functional speciﬁcations

Characteristic Speciﬁcation

Printing process Electro-photographic, four color (CMYK), two transfer printing using

Color medium Four toner cartridges each containing one of four colors: cyan,

Addressability 600 x 600 dpi and 600 x 1200 dpi Print speed Time from paper load to paper eject:

Minimum margins

Usable papers sizes

Usable paper weights 75 to 105 g/m

Tray capacities Main tray:

modulated (on/off) laser beam scanning. Imaged is fused to paper using heat and pressure with silicone oil lubricant.

magenta, yellow or black. The toner is a nonmagnetic, dual component contact medium.

A-size: Four color: 4 pages per minute Monochrome: 16 pages per minute Transparency: 2 pages per minute B-size: Four color: 2 pages per minute Monochrome: 8 pages per minute Transparency: 1 page per minute

5 mm(0.2 in.) on all sides, except for Tabloid Plus (13 x 19 in.) media which has a bottom margin of 25 mm (1 in.)

Paper

Envelope

3.5x5.5, minimum size US #10

8.5x11, Letter Euro Standard

8.5x14, Legal A4 11x17, Tabloid C4 12x18, Tabloid Extra C5 13x19, Tabloid Plus C6 A3 C65 A4 A5 B4 B5 Avery label: 5164, 5663, 7330, 7348

(20 to 24 lb) thru paper tray.

64 to 220 g/m2(80 lb) using the multi-purpose tray

Standard paper: 250 sheets Transparency: 100 sheets Lower feeder trays: Standard paper: 250 sheets Multi-purpose tray: Standard paper/Letterhead: 150 sheets Transparency: 50 sheets Label: 50 sheets Postcard: 75 Envelope: 30 Glossy/Coated: 75 Index: 30 Fabric Transfer: one at a time

Service Guide

Table 5 Electrical speciﬁcations

Characteristic Speciﬁcation

Primary line voltage 100/120 VAC (+/- 10%)

Primary voltage frequency range

Power consumption EnergyStar: 20 watts

220/240 VAC (+/- 10%) 47 to 63 Hz

Standby: 100 watts 1000 watts with fuser on

Ready: 100 watts 1000 watts with fuser on

Printing: 1100 watts

Table 6 Environmental speciﬁcations

Characteristic Speciﬁcation

Temperature: Operating Non-operating Storage

Humidly: Operating Non-operating Storage

0 to 32oC (41 to 90oF)

-20 to40oC (-4 to 104oF)

15 to 85% relative humidity 5 to 85% relative humidity 5 to 85% relative humidity

Altitude Operating: Non-operating

Vibration Operating:

Non-operating Shock-non-operating

Acoustic Noise Idle: Printing:

Phaser 780 Color Printer

0 to 3000 m (9900 ft.) at 25 0 to 15000 m (50,000 ft.)

Will withstand 0.5G excitation, 5 to 100 Hz, 3 axes for up to 50 minutes with no impairment or subsequent damage.

0.5 g, 25 minute sweep, 5-100 Hz, 100-200 sec/sweep cycles The printer may have any corner raised and dropped 5 cm (2 in.) without impairment of operation.

38.3 db

54.8 db with impulse noise of 63.3 db

Regulatory speciﬁcations

Safety

■ EN60950 CB Report by Third Party GOST and TUV certiﬁcation

■ UL1950 Nationally Recognized Test Lab (NRTL) certiﬁed

■ CSA 950 SCC recognized test lab certiﬁed

EMC

■ EN55022 (CISPR 22) Class B

■ EN50082-1:1994 Susceptibility

■ EN61000-3-2 AC Mains Harmonic Distortion

■ EN61000-3-3 AC Mains Voltage Flicker

■ EN61000-4-2:1993 ESD

■ EN61000-4-4:1993 Fast Burst Transients

■ EN61000-4-5:1993 Line Surge

■ EN61000-4-11;1993 Voltage Dips and Interruptions

■ ENV50140:1993 Radiated RF Immunity

Energy Star certiﬁcation

After 1-hour period of inactivity, the printer enters an standby mode, as required by Energy Star . The wait time is a user -deﬁnable parameter (via the fr ont panel or by using PhaserLink). Energy Star default is “ON” and the time-out default is one hour. The printer enters a READY condition within 5 minutes after poweron.

Service Guide 17

18 Phaser 780 Color Printer

Error Codes and Messages

The following table list error codes and messages reported by the print engine control board.

Error code and message

Laser Unit Error (Error 10)

Image Density Error (Error 11)

Description Corrective action

There is a problem with the laser unit. The engine control board did not receive a signal from the laser start-of-scan sensor within the speciﬁed time

The image density readings indicate a problem. The engine control board detected that the printer image density was unusually low and attempts to raise the density have failed.

Note

If the top cover is removed, light can leak into the printer and cause a auto-density calibration sensor error.

Test the top cover and right

front cover switches for proper operation. Power for the laser unit is routed through both switches Replace the laser unit.

Replace the engine control

board

Power cycle the printer Inspect the toner cartridges.

Inspect the four developer

housings. Each magnetic roller should be evenly coated with toner. Replace a suspect developer assembly. Test the toner/developer

dispense motor. Replace it if it does not run Inspect and reseat the

auto-density calibration sensor. Ensure the senor’s solenoid-activated cleaning blade is in place and moves freely. Test the auto-density

calibration sensor. If bad, replace the auto-density calibration sensor Replace the imaging unit

Replace the engine control board

Replace the high voltage board

Service Guide

Error code and message

Image Density Error (Error 12)

Description Corrective action

The image density readings indicate a problem. The engine control board detected that the printer image density was unusually high and attempts to lower the density have failed.

Power cycle the printer

Ensure the toner cartridges are fully functional and relatively full of toner. Test the toner dispense

motor.

Check the auto-density calibration sensor for contamination from toner. Replace the sensor, if necessary.

Inspect and reseat the auto-density calibration sensor. Ensure the senor’s solenoid-activated cleaning blade is in place and moves freely. Test the auto-density

calibration sensor. If bad, replace the auto-density calibration sensor

Replace the engine control board Inspect the four developer

housings. Each magnet roller should be evenly coated with toner. Replace a suspect developer assembly.

Replace the imaging unit

10.

Replace the high voltage

board

Phaser 780 Color Printer

Error code and message

Autodensity Calibration Error (Error 13)

Toner Carousel Error (Error 21)

Description Corrective action

There is problem with the auto-density calibration. The engine control board detected that the auto-density calibration sensor LED output signal is below speciﬁed range.

Power cycle the printer Check the auto-density

calibration sensor for contamination from toner. Replace the sensor, if necessary. Inspect and reseat the

auto-density calibration sensor. Ensure the senor’s solenoid-activated cleaning blade is in place and moves freely.

Test the auto-density calibration sensor. If bad, replace the auto-density calibration sensor Replace the engine control

board

Replace the low voltage power supply

There is a problem with the carousel home sensor. The engine control board detected that the carousel home sensor did not actuate within six seconds after the start of the carousel motor.

Power cycle the printer

Manually rotate the carousel assembly several revolutions

Check for contamination that may cause binding. Test the carousel home

sensor. Replace if needed

Replace the carousel motor

Replace the engine control board

PCDC Error (Error 22)

Environment Sensor Error (Error 23)

There is a problem with PCDC calibration. The engine control board detected that PCDC calibration value is much lower than set speciﬁcations.

There is a problem with the environment sensor circuit. The engine control board detected an open environment sensor circuit

Power cycle the printer

Inspect the process drive. Ensure the drum rotates Replace the engine control

board

Replace the image processor board

Power cycle the printer Replace the environment

sensor

Replace the engine control board

Service Guide

Error code and message

Second Bias Transfer Roller Error (Error 24)

Fuser Temperature Error (Error 40)

Description Corrective action

The engine control board detected that the measured current value thru the second bias transfer roller was not within speciﬁcation.

Check the wiring from the

high voltage power supply to the second bias transfer roller

Replace the second

bias transfer roller

Replace the high voltage power supply

Replace the accumulator belt assembly

Replace the engine control board

There is a problem with the temperature of the fuser. The engine control board detected that the fuser temperature did not reach 110˚C within six minutes after the printer was turned on.

Open the fuser door and

ensure the fuser connectors are properly seated.

Close the fuser and power cycle the printer. Check that the fuser heats up Check for line voltage at P/J

71 pins 1 and 2. If no v oltage is present replace the power supply Replace the fuser

Replace the engine control

board

Fuser Temperature Error (Error 41)

There is a problem with the fuser heat rod control. The engine control board detected that the fuser heat rods remained on longer than the speciﬁed time.

Phaser 780 Color Printer

Open the fuser door and ensure the fuser connectors are properly seated.

Close the fuser and power cycle the printer. Check that the fuser heats up Check for line voltage at P/J

71 pins 1 and 2. If no v oltage is present replace the power supply Replace the fuser

Replace the engine control

board

Error code and message

Fuser Temperature Error (Error 42)

Fuser Temperature Error (Error 43)

Description Corrective action

There is a problem with the fuser. The engine control board senses an open temperature sensor circuit.

Open the fuser door and ensure the fuser connectors are properly seated.

Close the fuser and power cycle the printer. Check that the fuser heats up Check for line voltage at P/J

71 pins 1 and 2. If no v oltage is present replace the power supply Replace the fuser

Replace the engine control

board

There is problem with the fuser. The engine control board detected that the fuser did not reach ready temperature during the speciﬁed time.

Open the fuser door and ensure the fuser connectors are properly seated. Close the fuser and power

cycle the printer. Check that the fuser heats up Check for line voltage at P/J

71 pins 1 and 2. If no v oltage is present replace the power supply

Replace the fuser Replace the engine control

board

Fuser Temperature (Error 44)

The thermistor sensor indicates that the fuser had reached the set overheat temperature, The engine control board has shutdown fuser temperature operation.

Allow the fuser to cool for 30 minutes

Ensure the fuser wiring harnesses are plugged in. Check the fuser fan

Replace the fuser

Replace the engine control board Replace the low voltage

power supply

Service Guide

Error code and message

Process Motor Error (Error 61)

Paper Handling Motor Error (Error 62)

Imaging Unit ID Error (Error 69)

Description Corrective action

There is a problem with the process motor. the engine control board did not receive a signal from the accumulator belt home sensor signal in the speciﬁed time.

Test the process drive

assembly

Test the +24 VDC at P/J 32-11 and frame ground. Test the accumulator belt

home sensor

Replace the process motor.

Replace the accumulator belt assembly Replace the engine control

board

Replace the imaging unit

There is a problem with the paper feed motor. The engine control board received a failed signal from the paper feed motor circuitry.

Power cycle the printer

Replace the paper feed

motor

Replace the engine control board Check for mechanical binding

in the paper feed drive gear train

The engine control board detected a used CRUM

Reseat the imaging unit

Power cycle the printer Replace the imaging unit

Replace the engine control

board

Imaging Unit ID Error (Error 70)

Imaging Unit ID Error (Error 71)

Imaging Unit Count Error (Error 72)

There is a CRU Memory problem. The engine control board detected that the memory initial value of the installed imaging unit is wrong.

An incompatible imaging unit is installed in the printer. The engine control board detected that the memory device in the installed imaging unit is incompatible with the printer.

There is a CRU memory problem. The engine control board could not read the CRUM counter value.

Phaser 780 Color Printer

Reseat the imaging unit Power cycle the printer

Replace the imaging unit

Replace the engine control board

Power cycle the printer Reseat the imaging uni

Switch the printer power off,

then on

Replace the engine control board

Power cycle the printer

Replace the imaging unit with a new cartridge

Replace the engine control board

Error code and message

Imaging Unit ID Error (Error 73)

Imaging Unit Comm Error (Error 74)

Imaging Unit Comm Error (Error 75)

Engine Board Error (Error 76)

Description Corrective action

The wrong imaging unit is installed in the printer. The engine control board detected that the installed imaging unit is incompatible with the printer.

Power cycle the printer Replace the imaging unit with

a new cartridge

Replace the engine control board

There is a CRU memory problem. The engine control board could not write to the CRUM.

Power cycle the printer Reseat the imaging unit in the

printer

Replace the imaging unit with a new cartridge Replace the engine control

board

There is a CRU Memory problem. The engine control board could not communicate with the CRUM.

1. Power cycle the printer

2. Replace the imaging unit with

a new cartridge

3. Replace the engine control

board

The engine control board detected a corrupted NVRAM during power-on self test

1. Power cycle the printer

2. Replace the NVRAM

chip

3. Replace the engine control

board

ROM/ RAM Error (Error 77)

There is a problem in reading information from ROM or RAM on the engine control board. The engine control board could not read information on the ROM or RAM.

1. Power cycle the printer

2. Check if +5 VDC is supplied

at P/J33-3 and frame ground. If not, replace the low voltage power supply

3. Replace the engine control

board

Service Guide

Error code and message

Description Corrective action

Image Contains T oo Much Coverage

Replace Fuser Roll Cartridge

Waste Cartridge Full

Image density exceeded design speciﬁcations. The engine control board detected that the ﬁrst 70mm of the lead edge of the four color image about to be printed exceeds the design speciﬁcation for total image density . The speciﬁcation is 280% or less image density. For example, a density setting of 100% for each of the four colors creates a layered four color image with a combined density of 400%.

The fuser oil roll has reached end of life. The engine control board detected that the fuser oil roll has processed the equivalent of 20,000 sheets of paper since it was installed.

The waste cartridge is full. The engine control board detected that the waste cartridge sensor was on for 1250 print cycles.

1. Power cycle the printer

2. Print a less complex, color

image to determine if it is overly dense.

3. Replace the engine control

board

1. Replace the fuser roll

cartridge

2. Power cycle the printer

3. Ensure the fuser connectors

are properly seated

4. Test the fuser using internal

diagnostics

5. Replace the engine control

board

1. Replace the waste cartridge

2. Test the waste cartridge full

sensor using internal diagnostics

3. Inspect the electrical

contacts and wiring Replace the waste cartridge full sensor

4. Replace the engine control

board

Replace Black Toner Cartridge

Black image density is too low. The engine control board detected that the auto-density calibration sensor reads the black patch density as being below speciﬁcation and that the reading is either slow to raise or does not raise after the printer attempts to increase density.

26 Phaser 780 Color Printer

1. Replace the black toner

cartridge

2. Test the toner/developer

dispense motor

3. Test the auto-density

calibration sensor

4. Replace the engine control

board

Error code and message

Description Corrective action

Replace Cyan Toner Cartridge

Replace Magenta Toner Cartridge

Replace Yellow Toner Cartridge

Cyan image density is too low. The engine control board detected that the auto-density calibration sensor reads the cyan patch density as being below speciﬁcation and that the reading is either slow to raise or does not raise after the printer attempts to increase density.

Magenta image density is too low. The engine control board detected that the auto-density calibration sensor reads the magenta patch density as being below speciﬁcation and that the reading is either slow to raise or does not raise after the printer attempts to increase density.

Yellow image density is too low. The engine control board detected that the auto-density calibration sensor reads the yellow patch density as being below speciﬁcation and that the reading is either slow to raise or does not raise after the printer attempts to increase density.

1. Replace the cyan toner

cartridge

2. Test the toner/developer

dispense motor

3. Test the auto-density

calibration sensor

4. Replace the engine control

board

1. Replace the magenta toner

cartridge

2. Test the toner/developer

dispense motor

3. Test the e auto-density

calibration sensor

4. Replace the engine control

board

1. Replace the yellow toner

cartridge

2. Test the toner/developer

dispense motor

3. Test the auto-density

calibration sensor

4. Replace the engine control

board

Replace Imaging Unit

Fuser Roll Cartridge Low

The imaging unit has reached end of life. The engine control board detected that the installed imaging unit has reached end of life.

The fuser oil roll is nearing end of life. The engine control board detected that the fuser oil roll is nearing the 20,000 mark.

1. Replace the imaging unit

2. Switch the printer power off,

then on

3. Inspect the CRUM for

damage or contamination. clean or replace if necessary.

4. Replace the engine control

board

1. Replace the fuser oil roll

2. Replace the engine control

board

Service Guide 27

Error code and message

Description Corrective action

Waste Cartridge Almost Full

Black Toner Low

Cyan Toner Low

Magenta Toner Low

The waste toner box is almost full. The engine control board detected that the waste toner box is almost full and will soon need to be replaced.

The black toner cartridge is low on toner. The engine control board switched on the dispense motor for more than 980 seconds in order to raise the image density to normal.

The cyan toner cartridge is low on toner. The engine control board switched on the Dispense Motor for more than 800 seconds in order to raise the image density to normal.

The magenta toner cartridge is low on toner. The engine control board switched on the Dispense Motor for more than 800 seconds in order to raise the image density to normal.

1. Replace the waste toner box

2. Replace the engine control

board

1. Replace the black toner

cartridge

2. Test the dispense motor

3. Test the auto-density

calibration. Replace it, if necessary.

4. Replace the engine control

board

1. Replace the cyan toner

cartridge

2. Test the dispense motor

3. Test the auto-density

calibration. Replace it, if necessary.

4. Replace the engine control

board

1. Replace the magenta toner

cartridge

2. Test the dispense motor

3. Test the auto-density

calibration. Replace it, if necessary.

4. Replace the engine control

board

Yellow Toner Low

The yellow toner cartridge is low on toner. the engine control board switched on the Dispense Motor for more than 1150 seconds in order to raise the image density to normal.

28 Phaser 780 Color Printer

1. Replace the yellow toner

cartridge

2. Test the dispense motor

3. Test the auto-density

calibration. Replace it, if necessary.

4. Replace the engine control

board

Error code and message

Description Corrective action

Media Low in Tray 4

Media Low in Tray 3

Media Low in Tray 2

Media Low in Tray 1

The engine control board detected that the tray 4 low paper sensor is actuated.

The engine control board detected that the tray 3 low paper sensor is actuated.

The engine control board detected that the tray 2 low paper sensor is actuated.

The engine control board detected that the Tray 1 Low Paper Sensor is actuated.

1. Add paper to tray 4

2. Check for a damaged or

missing sensor actuator.

3. Replace the tray 4 low sensor

4. Replace the engine control

board

1. Add paper to tray 3

2. Check for a damaged or

missing sensor actuator.

3. Replace the tray 3 low sensor

4. Replace the engine control

board

1. Add paper to tray 2

2. Check for a damaged or

missing sensor actuator.

3. Replace the tray 2 low sensor

4. Replace the engine control

board

1. Add paper to tray 1

2. Check for a damaged or

missing sensor actuator.

3. Replace the tray 1 low sensor

4. Replace the engine control

board

Load Media in Multipurpose T ray

Load Media in T ra y 4

The multi-purpose tray is out of paper. The engine control board detected that the long multi-purpose tray paper sensor is not actuated.

Tray 4 is out of paper. The engine control board detected that the paper empty sensor in tray 4 is actuated.

1. Load paper into the

multi-purpose tray

2. Test the multi-purpose tray

paper sensors

3. Replace the engine control

board

1. Load paper into Tray 4

2. Test the paper empty sensor

3. Replace the lower feeder

circuit board

4. Replace the lower feeder

assembly

5. Replace the engine control

board

Service Guide 29

Error code and message

Description Corrective action

Load Media in T ra y 3

Load Media in T ra y 2

Load Media in T ra y 1

T r ay 3 is out of paper . The engine control board detected that the paper empty sensor in tray 3 is actuated.

T r ay 2 is out of paper . The engine control board detected that the paper empty sensor in tray 2 is actuated.

T r ay 1 is out of paper . The engine control board detected that the paper empty sensor in tray 1 is actuated.

1. Load paper into Tray 3

2. Test the tray’s paper empty

sensor

3. Replace the lower feeder

circuit board

4. Replace the lower feeder

assembly

5. Replace the engine control

board

1. Load paper into Tray 2

2. Test the tray’s paper empty

sensor

3. Replace the lower feeder

circuit board

4. Replace the lower feeder

assembly

5. Replace the engine control

board

1. Load paper into Tray 1

2. Test the tray’s paper empty

sensor

3. Replace the lower feeder

circuit board

4. Replace the engine control

board

Clear Jam At A, B

The engine control board detected that the registration sensor was actuated while the printer was in standby.

30 Phaser 780 Color Printer

1. Clear jammed paper from the

printer

2. Test the feeder registration

exit sensor

3. Replace the engine control

board

Error code and message

Description Corrective action

Clear Jam At A, B

Clear Jam At C, D

There is a problem near the registration sensor. The engine control board detected that the registration sensor did not actuate within the speciﬁed time after paper feed.

There is problem at the fuser exit sensor. The engine control board detected that the fuser exit sensor was actuated while the printer was in standby.

There is problem near the fuser exit sensor. The engine control board detected that the fuser exit sensor did not actuate within the speciﬁed time after the fuser entrance sensor was actuated.

1. Clear jammed paper from the

printer

2. Check that the media tray

and ensure it is correctly loaded

3. Test the pre-registration

clutch

4. Test the registration clutch

5. Test the paper feed motor

6. Check the operation of the

paper pick solenoid

7. Inspect the paper path

8. Clean the feed rollers

9. Test the registration sensor

10. Run the paper path test

11. Replace the engine control

board

1. Clear jammed paper from the

printer

2. Test the fuser exit sensor

3. Replace the engine control

board

1. Clear jammed paper from the

printer

2. Test the fuser exit sensor

3. Inspect the paper path

4. Inspect the fuser chute fan

5. Replace the fuser

6. Inspect the fuser drive gear

train. Replace if necessary

7. Replace the paper feed

motor.

8. Replace the engine control

board

Clear Jam at EThere is problem at the media exit

sensor. The engine control board detected that the top exit sensor was actuated while the printer was in standby.

1. Clear jammed paper from the

printer

2. Test the feeder media exit

sensor

3. Inspect the paper exit path

4. Replace the engine control

board

Service Guide 31

Error code and message

Description Corrective action

Clear Jam At EThe engine control board detected that

the media exit sensor did not actuate within the speciﬁed time after the fuser exit sensor actuated.

Media Size Mismatch

The engine control board detected that the paper that was fed into the printer was not the same size that was detected by the tray size sensors . The registration sensor monitors the timing of the paper as it runs through the printer.

Install Black Toner Cartridge

The black toner cartridge is either not installed or not installed correctly. The engine control board did not receive a signal from the cartridge sensor when the carousel frame moved the black developer housing into position.

1. Clear jammed paper from the

printer

2. Inspect and clean the exit

rollers

3. Test the media exit sensor

4. Inspect and test the paper

feed gear train and paper motor

5. T est the fuser driv e gear train

and exit guide

6. Replace the engine control

board

1. Set paper tray guides or use

another paper tray

2. Inspect the actuators at the

rear of the paper tray.

3. Test the paper tray size

sensors

4. Replace the paper tray size

sensor board.

5. Replace the engine control

board

1. Reseat the black toner

cartridge. Power cycle the printer

2. Replace the black toner

cartridge

3. Replace the toner cartridge

presence sensor.

4. Replace the engine control

board.

Install Cyan Toner Cartridge

The cyan toner cartridge is either not installed or not installed correctly. The engine control board did not receive a signal from the cartridge sensor when the carousel frame moved the cyan developer housing into position.

32 Phaser 780 Color Printer

1. Reseat the cyan toner

cartridge. Power cycle the printer

2. Replace the cyan toner

cartridge

3. Replace the toner cartridge

presence sensor.

Error code and message

Description Corrective action

Install Magenta Toner Cartridge

Install Y ellow Toner Cartridge

Install Waste Cartridge

Install Tray 1

The magenta toner cartridge is either not installed or not installed correctly. The engine control board did not receive a signal from the cartridge sensor when the carousel frame moved the magenta developer housing into position.

The yellow toner cartridge is either not installed or not installed correctly. The engine control board did not receive a signal from the cartridge sensor when the carousel frame moved the yellow developer housing into position.

The waste toner box is not installed. The engine control board detected that the waste toner box sensor was deactuated.

The engine control board did not detect a paper tray installed in Tray 1 slot.

1. Reseat the magenta toner

cartridge. Power cycle the printer

2. Replace the magenta toner

cartridge

3. Replace the toner cartridge

presence sensor.

1. Reseat the yellow toner

cartridge. Power cycle the printer

2. Replace the yellow toner

cartridge

3. Replace the toner cartridge

presence sensor.

4. Replace the engine control

board.

1. Reseat waste cartridge

2. Power cycle the printer

3. Test the waste toner sensor

4. Check the sensor wiring

5. Replace the sensor

6. Replace the engine control

board

1. Reseat the tray into the main

feeder slot

2. Inspect the tray’s switch

actuators for damage

3. Replace the paper size

sensor assembly

4. Replace the engine control

board

Install Tray 2

The engine control board did not detect a Paper Tray installed in Tray 2 slot.

1. Reseat the tray into the

second feeder slot

2. Inspect the tray’s switch

actuators for damage

3. Replace the paper size

sensor assembly

4. Inspect the lower

feeder-to-printer connections at the back of the printer.

5. Replace the engine control

board

Service Guide 33

Error code and message

Description Corrective action

Install Tray 3

Install Tray 4

Install Imaging Unit

The engine control board did not detect a Paper Tray installed in Tray 3 slot.

The engine control board did not detect a Paper Tray installed in Tray 4 slot.

The imaging unit is either not installed or not installed correctly. The engine control board did receive a signal from the customer replaceable unit memory.

1. Reseat the tray into the third

feeder slot

2. Inspect the tray’s switch

actuators for damage

3. Inspect the lower

feeder-to-printer connections Replace the paper size sensor assembly

4. Replace the engine control

board

1. Reseat the tray into the f ourth

feeder slot

2. Inspect the tray’s switch

actuators for damage

3. Inspect the lower

feeder-to-printer connections Replace the paper size sensor assembly

4. Replace the engine control

board

1. Reseat the imaging unit

2. Inspect the CRUM connector

for damage or contamination. Clean or replace if necessary

3. Replace the imaging unit

4. Replace the engine control

board

Install Fuser Roll

The engine control board detected that the fuser oil roll assembly circuit is open.

Cartridge

34 Phaser 780 Color Printer

1. Reseat the fuser oil roll

2. Inspect the fuser roll contacts

and connectors. Ensure the y are clean and seated correctly

3. Replace the fuser roll

4. Replace the engine control

board

Error code and message

Description Corrective action

Second Bias Transfer Roller Error

Replace Fuser

Printer Maintenance Required Replace the Accumulator Belt Cleaner

Printer Maintenance Required

The engine control board detected that the measured current value across second bias transfer roller was not within speciﬁcations.

The fuser has reached end of life. The engine control board detected that the fuser has processed 250,000 images or the toner dispense motor has accumulated more than 70,564 x 100ms of running time.

The accumulator belt cleaner is nearing end of life. The engine control board detected that the accumulator belt cleaner processed 100,000 sheets of paper.

The accumulator cleaner belt has reached end of life. The engine control board detected that the accumulator belt cleaner has processed over 102,000 belt clean cycles.

1. Power cycle the printer

2. Replace the high voltage

power supply

3. Replace the engine control

board

4. Replace the second bias

transfer roller

5. Replace the accumulator belt

assembly

1. Use diagnostics to verify the

print count

2. Replace the fuser

3. Replace the engine control

board

1. Use diagnostics to verify the

print count

2. Replace the accumulator belt

cleaner

3. Replace the engine control

board

1. Use diagnostics to verify the

print count

2. Replace the accumulator belt

cleaner

3. Replace the engine control

board

Printer Maintenance Required Replace the Second Bias Transfer Roller

The second bias transfer roller is nearing the end of its life. The engine control board detected that the second bias transfer roller has processed 100,000 sheets of paper.

1. Use diagnostics to verify the

print count

2. Replace the second bias

transfer roller

3. Replace the engine control

board

Service Guide 35

Error code and message

Description Corrective action

Printer Maintenance Required

Printer Maintenance Required Soon Imaging Unit Life Almost Over

Fuser Life Almost Over

Replace the imaging unit

The second bias transfer roller has reached end of life. The engine control board detected that second bias transfer roller has completed over 100,000 images.

The imaging unit has reached end of life. The engine control board detected that the drum inside the imaging unit has exceeded 90,000 revolutions.

The fuser is nearing end of life. The engine control board detected that the fuser processed 237,500 images or the toner dispense motor has accumulated more than 67,036 x 100ms of running time.

The imaging unit has reached end of life. The engine control board detected that the imaging unit has printed 110,000 images.

1. Use diagnostics to verify the

print count

2. Replace the second bias

transfer roller

3. Replace the engine control

board

1. Replace the imaging unit

2. Replace the engine control

board

1. Replace the fuser

2. Replace the engine control

board

1. Replace the imaging unit

2. Check the CRUM connector

for damage or contamination. Clean or replace if necessary

3. Replace the engine control

board

Close Lower Tray Assembly

The engine control board detected that the lower feeder cov er interlock s witch is deactuated.

Cover

36 Phaser 780 Color Printer

1. Close the feeder cover

2. Inspect the interlock switch.

Replace if necessary

3. Replace the feeder control

board

4. Inspect the lower

feeder-to-printer connections at the rear of the printer

5. Replace the feeder

6. Replace the engine control

board

Error code and message

Description Corrective action

Close Left Fuser Unit

Close Exit Cover

Close Right Feed Unit

Close Front Cover

The engine control board detected that the fuser interlock circuit is open.

The engine control board detected that the exit door switch is deactuated.

The engine control board detected that the paper feeder Interlock circuit is open.

The engine control board detected that the front cover interlock switch is deactuated.

1. Reseat the fuser

2. Inspect the fuser mating

connectors for proper ﬁt

3. Replace the engine control

board

1. Close the exit cover

2. Replace the exit chute switch

3. Replace the upper exit

assembly

4. Replace the engine control

board

1. Close the paper feeder

assembly

2. Inspect the mating

connectors of the paper feeder

3. Replace the paper feed

harness

4. Replace the paper feeder

5. Replace the engine control

board

1. Close the front cover

2. Inspect the cover’s switch

actuators. Replace the co ver if damaged

3. Test for +24 VDC at Pins

P32-8 and 3. You should measure 24 VDC at pin 3 through the right and left cover interlock switches bac k to pin 8.

4. Test for 5 VDC between

P33-1 and frame ground It should switch between 5 and 0 VDC when the front cover is opened and closed. If not replace the left front cover switch

5. Replace the low voltage

power supply

Service Guide 37

Error code and message

Description Corrective action

Empty the Top Output Tray

The engine control board detected that the full stack sensor is actuated for more than 12 seconds.

1. Remove the prints from

output tray

2. Inspect for damage the

output tray full sensor. Replace if necessary

3. Replace the engine control

board

Troubleshooting

System power-up sequence

The main power switch is turned on. (Or the front cover is opened and then closed or diagnostics are exited.)

The print engine reads the Customer Replaceable Unit Memory (CRUM).

The print engine determines that all the CRUs are in place, except for the toner cartridges.

The print engine checks its sensors for any static jam errors.

The print engine reads all life counters in NVRAM.

The print engine applies voltage to the fuser to bring it up to standby temperature.

The process motor energizes and then a 1/4 second later, the paper feed motor is energized.

The print engine powers on the carousel motor and checks the presence of the four toner developer assemblies.

The print engine veriﬁes proper operation of the image process components. The auto-density calibration sensor checks the density levels.

10.

The print engine initiates a cleaning cycle of the accumulator belt.

11.

The process motor is de-energized.

12.

The print engine updates the NVRAM

13.

The print engine updates the CRU memory.

14.

The paper feed motor is de-energized.

The print engine is initialized.

Service Guide

Print engine troubleshooting

Printer will not power up

When you switch on the printer, the control panel does not light, the fans do not rotate, the carousel motor does not cycle, and the printer does not go into warmup.

110VAC IN Check

Inspect the AC Power Cord. Is the AC Power Cord plugged into the printer, and is the other end plugged into an AC wall outlet?

Check the voltage at the AC wall outlet. Is there approximately 110 VAC (or 220 VAC if the printer is the 220 VAC model) at the AC wall outlet?

Remove the rear cover.

Measure the voltage between the two low voltage power supply solder points located next to the AC power jack. Is there 110 VAC between the two points?

Low voltage power supply check

Measure the voltage between P33-3 on the low voltage power supply and frame ground. Is there +5 VDC between P33-3 and frame ground. If not, replace the low voltage power supply.

Check for +24VDC between P32-3 on the low voltage power supply and frame ground. Replace the low voltage power supply. Check for +24VDC between P32-8 and frame ground. If voltage is at pin 3 but not at pin 8, check the front cover, fuser and paper feeder interlock switches. Is there +24VDC between P32-11 and frame ground? If not, replace the power supply. Check for a short in the 24 volt components (particularly on the paper feed motor circuit board).

Low voltage power supply loading check

Disconnect P32 and P33 from the low voltage power supply.

Measure the voltage between P33-3 on the low voltage power supply and frame ground, and between P32-11 on the low voltage power supply and frame ground. Is there +5 VDC between P33-3 and frame ground, and is there +24 VDC between P32-11 and frame ground? If not, replace the low voltage power supply.

Engine control board loading check

Reconnect P32 and P33 to the low voltage power supply.

Refer to “Wiring Diagrams” on page 185 and one by one disconnect components that are connected to the engine control board.

Phaser 780 Color Printer

Measure the voltage between P33-3 on the low voltage power supply and frame ground, and between P32-11 on the low voltage power supply and frame ground. Do you eventually measure +5 VDC between P33-3 and frame ground, and +24 VDC between P32-11 and frame ground? If yes, replace the component that is loading down the power supply. If no, replace the engine control board.

Image processor check

Turn off the printer.

Remove the image processor board.

Turn on the printer. Does the printer go into warm-up? If yes, replace the image processor board. If not, replace the engine control board.

Erratic printer operation

The printer has a variety of intermittent problems, but generally does not complete a print cycle. The problems are generally not identiﬁed by displayed error codes.

Does the printer frequently fail to enter printer warm-up or is the front panel frequently inoperative? If yes, follow the earlier procedure “Printer will not power up” on page 40.

Run print engine test prints, which print independently of the image processor, to determine if the image processor is the problem. Refer to “Making a print engine only test print” on page 42.

Low voltage power supply loading check

Run 50 test prints from the image processor’s built in test prints.

Measure the voltage between P33-3 on the low voltage power supply and frame ground, and between P32-11 on the low voltage power supply and frame ground. Is there a steady +5 VDC between P33-3 and frame ground, and is there at steady +24V DC between P32-11 and frame ground? If no, Replace the low voltage power supply.

If test prints from the image processor print reliably, reload the host’s printer driver software or the host application software. Does the printer still exhibit erratic operation?

Try printer from another application. Ensure that the host computer prints reliable to a different printer. Also try printing from another computer to the Phaser 780.

Replace the interface cable connecting the host to the printer.

Replace the engine control board.

Replace the image processor board.

Service Guide

Making a print engine only test print

Using the image processor.

Turn off the printer.

Remove the right side panel to access the image processor board.

Locate switch 4 of S930 on the image processor board. Closing switch 4 bypasses the image processor board and places the engine control board into test mode upon power up.

Turn on the printer.

The printer generates process black (all four colors layered) grid patterns. The printer feeds from the ﬁrst tray that has paper - in this order; Tray 1, T ray 2, Tray 3, T ray 4, and multi-purpose feeder. The printer sends the test prints to the face down output tray. The printer generates test prints until you stop the test.

Switch off printer main power to stop generating test prints.

Move the S930 switch 4 to the off (open) position.

Using the print engine board.

installed.

Turn off the printer.

Remove the image processor so you can access the engine control board.

Locate JP3, just below the ROM chip on the engine control board.

Move the switch to the ON position.

Turn on the printer.

The printer generates test prints just as it does in the previous procedure.

Switch off printer main power to stop generating test prints.

Move the switch to the 1 position.

To generate a test print without the image processor

Phaser 780 Color Printer

Printing and print quality problems

Initial checks and actions

Does the printer display an error code? If so go to “Error Codes and Messages” on page 19.

Is the AC power provided at the wall outlet within recommended speciﬁcations?

Is the printer properly gounded through the AC wall outlet?

Is the printer located in an area where the temperature and humidity are stable and within speciﬁcations?

Is the printer located in an area free of dust?

Is the printer located away from water outlets, steamers, electric heaters, volatile gases, open ﬂames and strong radio frequency sources?

Is the printer shielded from the direct rays of the sun?

Does the printer have adequate clearances on all sides for proper ventilations?

Is the printer installed on a level, stable surface?

10.

Is the correct paper stock being used in the printer?

11.

Is the customer using the printer correctly as explained in the user documentation?

12.

Have the consumables been replaced correctly at the required intervals?

13.

Is the problem a failure or the result of improper use, incorrect media type/weight, excessive use or a limitation of the duty cycle?

Service Guide

Light (undertone) prints

The overall image density is too light. The printer displays no error code.

Inspect the paper that is loaded in the paper tray. Check that the paper is not wrinkled or moist. Also ensure it is the correct weight. Card stock must be feed from the multi-purpose tray. Recycled paper and paper less than 24 lbs may produce less than optimum quality.

Clean and inspect the autodensity calibration sensor . Test the sensor using the printer’s built-in diagnostics. If an error 11, 12, or 13 is detected, r eplace the auto-density calibration

3041-37

size paper and open the front cover just as the sheet of paper starts to exit the fuser. Inspect the image on the sheet of paper rollers. Is the image density normal before it r eached the fuser rollers? If no, go to Step 4. If yes, go to Step 7.

sensor.

Print Service Test Print 1 on B-

before

it reaches the fuser

Remove the imaging unit.

Inspect the test print image on the accumulator belt. Does the image appear completely transferred to the accumulator belt? If yes, replace the second bias transfer roller. If not, replace the accumulator belt.

Print Service Test Print 1 and inspect the image on the sheet of paper. Is the image density now normal? If not, replace the high voltage power supply.

Print Service T est Print 1 again and inspect the image on the sheet of paper

after

it exits the fuser rolls. Is the image light when it exits the fuser? If

yes, replace the oil roll cartridge.

Generate a test print.

Inspect the image on the sheet. Is the image density now normal as it exits the fuser? If not, replace the fuser.

Phaser 780 Color Printer

Blank prints

The entire image area is blank. The printer displays no error code.

Generate a test print. Is the test print blank? If no, reload the printer driver software or replace the image processor board.

Remove the imaging unit.

Inspect the empty imaging unit cavity for a sheet of paper that could be blocking the laser window.

Generate a test print and open the front cover just before the sheet of paper enters the fuser .

Remove the imaging unit.

Inspect the image on the

the drum? If not, make an engine-only test print. If a test print is printed, replace the image processor board. If not, replace the imaging unit.

Generate a test print. Is the test print blank? If yes, replace the high voltage power supply.

drum. Is there an image visible on

Inspect the image on the surface of the accumulator belt? Is there an image visible on the surface of the accumulator belt? If yes, replace the second bias transfer roller. If not replace the accumulator belt.

Replace the engine control board.

Service Guide

Monochrome prints

3041-38

No color is present in a color print, only the black layer is printed. The printer displays no error code. In some cases, depending on the nature of the failure, only a portion of the print may be monochrome while the remainder of the print is in color.

Check the accumulator belt cleaner for correct installation. The cleaning blade may be in constant contact with the accumulator belt, scraping off each layer of color toner soon after it is transferred.

Inspect the cleaner cam guides and holders located at the front and back of the fuser assembly. Are the cleaner cam holders seated properly? If not, reseat them as necessary.

Manually actuate the cleaner cam solenoid and rotate the fuser input gear to cycle the cleaner cam through its cycle of operation. Does the cleaner cam operate the cleaner cam guides properly? If not, replace the fuser assembly.

Replace the accumulator belt cleaner.

Phaser 780 Color Printer

Black prints

The entire image area is black. The printer displays no error code.

Power cycle the printer, if an error 10 is detected replace the laser scanner unit.

Replace the engine control board.

Print Service Test Print 1.

4. Is the test print completely

black? If no, reload the printer driver software or replace the image processor board.

5. Generate a test print and open

the front door just before the sheet of paper enters the fuser .

6. Remove the imaging unit.

drum. Is there a developed test print image visible on the drum? If no, replace the imaging unit.

8. Generate a test print. Is the test print black? Replace the high voltage

power supply.

7. Inspect the image on the

One color is faded

Toner cartridge is depleted or the toner developer is defective.

1. Replace the defective toner cartridge.

2. Replace the toner developer of the defective color.

Service Guide

3041-39

Missing band in direction of paper travel

Leading Edge

3041-40

1. Is the paper wrinkled, dimpled, or show any signs of having a high

moisture content? Load fresh, dry paper.

There are areas of the image that are extremely light or are missing entirely. These missing areas form wide bands that run along the page from leading edge to trailing edge in the direction of paper travel (B-size print shown). The printer displays no error code.

Note A-size prints are processed

through the printer with the short edge of the print parallel to the direction of the paper path making print artifacts parallel to the short edge of the print.

In B-size prints are processed through the printer with the long edge of the print parallel to the paper path making artifacts parallel to the long axis of the print.

2. Print Service Print 1. Do the bands appear in all four colors, If yes, go to

Step 3, If not, go to Step 7.

3. Remove the imaging unit. Inspect the empty cavity for a scrap of paper or

a toner blotch that could be blocking the laser window.

4. Generate a test print and open the front cover just before the sheet of

paper enters the fuser.

5. Remove the imaging unit.

6. Inspect the image on the drum. Is there a normal test print image, without

any vertical band deletions, visible on the drum? If yes, go to Step 9. If no, go to Step 7.

7. Remove the top cover.

8. Turn the carousel frame and inspect the magnetic rollers of each of the

four developer assemblies. Do the magnetic rollers of each developer assembly appear smooth, evenly formed, without any low spots, and without obvious contamination? If yes, replace the imaging unit. If not, replace the faulty developer assembly.

9. Inspect the image on the surface of the accumulator belt? Is there a

normal test image, without any band deletions, visible on the surface of the accumulator belt? If no, replace the accumulator belt.

10. Generate a test print and open the front cover just before the sheet of

paper enters the fuser.

48 Phaser 780 Color Printer

11. Inspect the image on the paper just before the paper enter the fuser. Is

Leadi

there a normal test print image, without any band deletions, visible on the sheet of paper? If not, replace the second bias transfer roller.

12. Generate a test print and slide the fuser assembly out of the printer just as

the sheet of paper exits the fuser.

13. Inspect the image on the sheet of paper just after the paper exits the fuser.

Is there a normal test print image on the sheet of paper before entering the fuser but the image has visible band deletions after it exits the fuser? If yes, replace the oil roll cartridge.

14. Generate a test print.

15. Inspect the image on the sheet. Is the image now normal, without band

deletions as it exits the fuser? If no, replace the fuser.

Missing bands in parallel to the leading edge

ng Edge

There are areas of the image that are extremely light or are missing entirely. These missing areas form wide bands that run across the page parallel with the leading edge of the print, perpendicular with the direction of paper travel (B-size print shown). The printer displays no error code.

Note A-size prints are processed

through the printer with the short edge of the print parallel to the direction of the paper path making print artifacts parallel to the long edge of the print.

In B-size prints are processed

3041-41

through the printer with the long edge of the print parallel to the paper path making artifacts parallel to the short axis of the print.

1. Inspect the paper that is loaded in the paper tray . Is the paper wrinkled,

dimpled, or show any signs of having a high moisture content?

2. Print Service Print 1. Do the bands appear in all four colors, If yes, go to

Step 3, If not, go to Step 11.

3. Generate a test print and open the front cover just before the sheet of

paper enters the fuser.

4. Remove the imaging unit.

Service Guide 49

5. Inspect the image on the drum. Is there a normal test print image, without

any band deletions, visible on the drum? If yes, go to Step 6. If not, replace the imaging unit.

6. Inspect the image on the surface of the accumulator belt? Is there a

normal test print image, without any horizontal band deletions, visible on the surface of the accumulator belt? If no, replace the accumulator belt.

7. Inspect the image on the sheet of paper just before the paper enter the

fuser. Is there a normal test print image, without any band deletions, visible on the sheet of paper? If not, replace the second bias transfer r oller .

8. Generate a test print and open the front cover just as the sheet of paper

exits the fuser.

9. Inspect the image on the sheet of paper just after the paper exits the fuser.

Is there a normal test print image on the sheet of paper before entering the fuser but the image has visible horizontal band deletions after it exits the fuser? If yes, replace the fuser roll cartridge.

10. Make another test print. If the problem still occurs, replace the fuser.

11. Remove the top cover.

12. Turn the carousel frame and inspect the magnet roller of each of the four

developer assemblies. Do the magnet rollers of each developer assembly appear smooth, evenly formed, without any low spots, and without obvious contamination? If not, replace the defective developer assembly.

13. Replace the high voltage power supply.

14. Replace each of the four developer assemblies, one at a time.

50 Phaser 780 Color Printer

Streaks in direction of paper travel

Leading Edge

3041-42

1. Inspect the paper path, between feed and exit, for contamination or

obstructions. Is the paper path free of contamination or obstructions?

2. Check for dirty fuser guide rollers. Also look for toner contamination on

the fuser’s temperature sensor.

There are dark lines running along the page in the direction of paper travel from the leading edge to the trailing edge (B-size print shown). The printer displays no error code.

Note A-size prints are processed

through the printer with the short edge of the print parallel to the direction of the paper path making horizontal print artifacts parallel to the shot edge of the print.

In B-size prints are processed through the printer with the long edge of the print parallel to the paper path making horizontal artifacts parallel to the long axis of the print.

3. Print Service Print 4 and open the front cover just before the sheet of

paper enters the fuser.

4. Remove the imaging unit.

5. Inspect the image on the drum. Is there a normal test print image,

without any streaks, visible on the drum? If yes, go to Step 6. If not, replace the imaging unit.

6. Inspect the image on the surface of the accumulator belt. Is there a

normal test print image, without any streaks, visible on the surface of the accumulator belt? If no, replace the accumulator belt. If yes, inspect the accumulator belt cleaner’s plastic shield for damage; replace the belt cleaner, if necessary. Replace the second bias transfer roller.

7. Generate a test print and open the front cover just as the sheet of paper

exits the fuser.

8. Inspect the image on the sheet of paper just after the paper exits the fuser.

Is there a normal test print image on the sheet of paper before entering the fuser but the image has visible streaks after it exits the fuser? If yes, replace the fuser roll cartridge. If streaks continue to occur, replace the fuser.

9. Remove the top cover.

Service Guide 51

10. Turn the carousel frame and inspect the magnet roller of each of the four

11. Replace the high voltage power supply.

Streaks parallel with the leading edge

Leading Edge

There are dark lines running parallel with the leading edge of the print, perpendicular to direction of paper travel (B-size print shown). The printer displays no error code.

Note A-size prints are processed

through the printer with the short edge of the print parallel to the direction of the paper path making print artifacts parallel to the long edge of the print.

In B-size prints are processed through the printer with the long edge of the print parallel to the paper path making artifacts parallel to the short axis of the print.

3041-43

streaks appear in all colors? If not, go to Step 8.

1.Print Service Print 1. Do the

2. Print Service Print 4 and open the front cover just before the sheet of paper

enters the fuser.

3. Remove the imaging unit.

4. Inspect the image on the drum. Is there a normal test print image, without

any horizontal streaks, visible on the drum? If yes, go to Step 4. If not, replace the imaging unit.

5. Inspect the image on the surface of the accumulator belt. Is there a normal

test print image, without any streaks, visible on the surface of the accumulator belt? If no, replace the accumulator belt. If yes, inspect the accumulator belt cleaner’s plastic shield for damage; replace the belt cleaner, if necessary. Replace the second bias transfer roller.

6. Print Service Print 4 and slide the fuser out of the printer just as the sheet

of paper exits the fuser.

7. Inspect the image on the sheet of paper just after the paper exits the fuser.

52 Phaser 780 Color Printer

8. Remove the top cover. Turn the carousel frame and inspect the magnet

roller of each of the four developer assemblies. Do the magnet rollers of each developer assembly appear smooth, evenly formed, without any low spots, and without obvious contamination? If not, replace the defective developer assembly.

9. Replace the high voltage power supply.

Banding

3041-44

There are three kinds of banding:

1. If a dark band appears every 364 mm from the leading edge of a B-size

print or occasionally on A-size print, reseat the imaging unit and print again. If the problem persists perform the procedure “Adjusting for impulse banding” on page 74.

2. If a dark band appears at a 1.3 to 1.7 mm pitch throughout solid ﬁlls,

replace the process drive assembly.

3. Dark bands appearing randomly in solid ﬁlls at pitches such as 44 mm, 88

mm or 104 mm. Replace the process drive assembly.

Edge of print is wrinkled with an area of ragged discoloration.

3041-45

The fuser roll cartridge is out of position.

1. Reseat the fuser roll cartridge

Service Guide 53

Random missing spots

There are small areas of the image that are extremely light or are missing entirely. These missing areas form spots that are localized to small areas of the page. The printer displays no error code. A small number of occasional missing spots is normal.

1. Inspect the paper that is

loaded in the paper tray. Ensure the paper is not wrinkled nor moist?

2. Random white spots with a

small grit-like center, usually occurring in cyan and magenta, can be caused by compacted toner. Print Service Print 5, 6, 7, or 8, which ever color applies, to

3041-46

3. Replace the affected toner cartridge. If problem continues replace that

color’s developer.

4. Generate a test print and open the front cover just before the sheet of

paper enters the fuser.

5. Remove the imaging unit. Inspect the image on the drum. Is there a

normal test print image, without any spot deletions, visible on the drum? If yes, go to Step 6. If not, replace the imaging unit.

6. Inspect the image on the surface of the accumulator belt? Is there a

normal test print image, without any spot deletions, visible on the surface of the accumulator belt? If no, replace the accumulator belt.

7. Inspect the image on the sheet of paper just before the paper enter the

fuser. Is there a normal test print image, without any spot deletions? If no, replace the second bias transfer roller.

8. Print Service Print 2 and open the front cover just as the sheet of paper

exits the fuser.

9. Inspect the image on the sheet of paper just after the paper exits the Fuser.

Is there a normal test print image on the sheet of paper before entering the fuser but the image has visible spot deletions after it exits the fuser? If yes, replace the fuser roll cartridge.

10. Make another test print. If the problem still occurs, replace the fuser.

11. Make a test print and the remove the top cover.

12. Turn the carousel frame and inspect the magnet roller of each of the four

purge out the toner of the affective color.

54 Phaser 780 Color Printer

Random spotting

3041-47

There are spots of toner randomly scatter ed across the page. The printer displays no error code.

1. Slide the paper feeder out of the printer and inspect the top of the

registration chute assembly. Is the top of the registration chute assembly free of toner and foreign debris? If not, remove and inspect the waste toner cartridge. Make sure the cartridge is not damaged or leaking.

2. If the spots appear in a single color, run 20 prints to consume the clumped

toner. If necessary, replace the toner cartridge.

3. Remove and inspect the imaging unit. Is the exterior of the imaging unit

clean and with no obvious toner leakage? If not, remove and inspect the waste toner cartridge. Make sure the cartridge is not damaged or leaking.

4. Remove the top cover.

5. Turn the carousel frame and inspect the four developer assemblies. Does

each developer assembly appear clean, without any obvious toner on the exterior of the assembly or falling from the magnetic brush? Clean the dirty developer assembly. If the problem reoccurs, replace the faulty developer assembly.

6. Inspect the fuser. Is the fuser free of toner? Clean the fuser, if necessary

by processing 10 sheets of B-size paper though it.

7. Remove and inspect the accumulator belt cleaner assembly. Is the

accumulator belt cleaner assembly clean and with no obvious toner leakage? If not clean or replace the accumulator belt cleaner assembly, if necessary.

8. With the accumulator belt cleaner assembly removed, inspect the

accumulator belt cleaner end of the auger. Is the auger clogged? Clean the printer interior.

9. Remove the rear cover.

10. With the accumulator belt cleaner assembly removed, watch the auger

drive gear as you manually rotate the paper feed motor. Does the fuser drive assembly rotate the auger drive gear? If not, replace the fuser drive assembly.

11. As you manually rotate the paper feed motor place your ﬁnger inside the

auger opening and feel the movement of the auger spring. Does the auger spring rotate when you manually rotate the paper feed motor? If not, replace the auger assembly.

12. Replace the imaging unit.

Service Guide 55

Repetitive mark appears on each print

3041-48

An identical mark or image appears on each, or every other, printed image.

1. If spots repeat every 264 mm (10.4 in.) or appear to move in the direction

of paper travel from print to print, replace the imaging unit. If a defect repeats in exactly the same place on successive prints, replace the accumulator belt assembly.

2. If a problem repeats every 117 mm (4.5 in.), r eplace the fuser. If a problem

repeats every 107 mm (4.25 in.), replace the fuser roll cartridge.

3. An 88 mm (3.5 in.) smear may occur on the ﬁrst print made after a new

imaging unit is installed due to the misalignment of the imaging unit’s gear teeth with its drive gear. Once printing starts, the teeth will mesh properly and the problem will disappear.

4. A defect every 58 mm (2.5 in.) or less is related to the feed or exit rollers.

Residual image or ghosting

There are faint, ghostly images appearing on the page. The images may be either from a previous page or from the page currently being printed. The printer displays no error code.

1. Was the customer printing

numerous copies of the same image? Avoid printing numerous copies of the same image.

2. Generate a test print and open the

front cover just before the sheet of paper enters the fuser.

3. Remove the imaging unit.

4. Inspect the image on the drum. Is

there a normal image, without ghosts, visible on the drum? If no,

3041-49

replace the erase lamp. (A failing high-voltage power supply can also cause ghosting.)

5. If the customer is consistently printing 250 B-size (500 A-size) prints a day,

recommend the Hi-Duty Fuser Roll Cartridge. If fuser damage is excessive, replace fuser and install Hi-duty Fuser Roll Cartridge.

56 Phaser 780 Color Printer

6. Replace the imaging unit. Excessive duplexing of the same image can

cause ghost images on the imaging unit drum from fuser oil contamination.

7. Inspect the image on the surface of the accumulator belt? Is there a

normal test print image, without ghosts, visible on the surface of the accumulator belt? If a ghost is present, visually inspect the operation of the cleaner cam solenoid and the cleaner cam guides located on the fuser assembly. If no ghost is present, replace the accumulator belt cleaner assembly.

8. Generate a test print and open the front cover just as the sheet of paper

exits the fuser.

9. Inspect the image on the sheet of paper just after the paper exits the Fuser.

Is there a normal test print image on the sheet of paper before entering the fuser but the image has ghost images after it exits the fuser? If yes, replace the fuser roll cartridge.

10. If ghosting continues, replace the fuser.

Background contamination

There is toner contamination on all or most of the page. The contamination appears as a very light gray dusting. The printer displays no error code.

1. Print Service Print 2 and open

the front cover just before the sheet of paper enters the fuser.

2. Remove the imaging unit.

Inspect the image on the drum. Is there a normal test print image, without background contamination, visible on the drum? If not, replace the high voltage power supply.

3. Inspect the image on the

surface of the accumulator belt? Is there a normal test print image, without

3041-50

4. Print service Print 2 and open the front cover just as the sheet of paper

exits the fuser.

5. Inspect the image on the sheet of paper just after the paper exits the fuser.

Is there a normal test print image on the sheet of paper before entering the fuser but the image has background after it exits the fuser? If so, replace the fuser roll cartridge.

6. If background contamination continues to occur after 20 prints, replace

the fuser.

background, visible on the surface of the accumulator belt? If not replace the accumulator belt assembly.

Service Guide 57

Unfused image or image easily rubs off of page

The toner image is not completely fused to the paper. The image easily rubs off. The printer displays no error code.

1. Is the image density very

2. Check the media weight and

3. Check the defaults set at the

4. Is the printed image fused to

3041-51

5. Replace the low voltage

6. Replace the engine control board

Toner on back of print

There is toner on the back of the printed sheet of paper.

light? If light, but not blank, go to the earlier topic “Light (undertone) prints” on page 44.

settings at the printer driver.

front panel for media size and type.

the paper. If not, replace the fuser.

power supply

1. Clean the printer interior

2. Inspect the paper that is loaded

in the paper trays. Is the paper clean and free of toner?

3. Generate a test print and open

the front cover just before the sheet of paper reaches the second bias transfer roller , about one second after the registration solenoid actuates.

4. Slide the paper feeder out of the

printer and inspect the back of the sheet of paper . Is the back of the sheet of paper clean and free of toner? If not clean the paper

3041-52

feeder and its metal and rubber registration rollers.

5. Generate a test print and open the front cover just before the sheet of

paper reaches the fuser.

58 Phaser 780 Color Printer

6. Open the front cover and inspect the back of the sheet of paper. Is the

back of the sheet clean and free of toner? If not, replace the second bias transfer roller and if necessary also replace the accumulator belt cleaner assembly.

7. Generate a test print and open the front cover just as the sheet of paper

exits the fuser.

8. Slide the fuser out of the printer and inspect the back of the sheet of

paper. Is the back of the sheet of paper clean and free of toner when it exits the fuser? If not, clean the fuser rollers, by processing 10 sheets of Bsize paper through the printer, or replace the fuser.

9. Generate a test print and open the upper exit cover just as the sheet of

paper reaches exit roller.

10. Inspect the back of the sheet of paper. Is the back of the sheet of paper

clean and free of toner as it nears the exit roller? If not, clean or replace the upper exit assembly.

Print is mottled

The printed image has a mottled appearance.

1. Ensure good quality laser paper is

being used.

2. Check the media settings at the

printer driver and at the front panel default settings for media size and type.

3. Does mottling occur on only one

color? If yes, remove the top cover and inspect the magnetic rollers of the affected color’s developer assembly. Ensure there is no buildup. Replace the developer if necessary.

4. Print Service Print 2 and open the

front cover just before the sheet of

3041-53

5. Inspect the image on the accumulator belt. Is there a normal image without

mottling on the belt? If not, replace the accumulator belt assembly.

6. Print a test print and open the front cover just before the sheet of media

reaches the fuser. Is there a normal image on the print without mottling. If not replace the second bias transfer roller.

7. If the image on a print is normal before it passes through the fuser but

mottled afterwards, replace the fuser roll cartridge. If the problem persists, replace the fuser.

media exits the fuser. Remove the imaging unit and inspect the image on the drum. Is there a normal image without mottling. If not replace the imaging unit.

Service Guide 59

Image mis-registered on paper

3041-54

4. Replace the paper feeder.

5. Replace the engine control board.

The image area is not centered on the page or the image is bleeding off of the page. The printer displays no error code.

1. Is the correct weight paper

correctly loaded in the tray(s) or multi-purpose tray? Ensure the paper guides are correctly set.

2. Clean or replace the pick rollers.

3. Print Service Print 3 and slide

the paper feeder out about 10 seconds after pressing Print. The paper should be evenly pre-registered 6 mm (1/4 in.) from the mylar registration guide. If correctly registered, test the registration clutch. Clean the registration rollers. If not, test the pick solenoid of the tray being used. Replace if needed.

Color layer not correctly registered

60 Phaser 780 Color Printer

The four color images are not registered correctly and do not form a clean, four color image on the page. The printer displays no error code.

1. Ensure the shipping blocks

are removed from the paper feeder.

2. T est the accumulator belt home

sensor. Replace it if necessary.

3. Replace the engine control

board.

4. Replace the image processor.

5. Replace the accumulator belt

assembly.

3041-55

Color representation not correct

Oil stain or gloss variation on print

The color of the printed image is completely different than the computer image. The printer displays no error code.

1. Ensure driver settings are

correct. Reload the printer driver software.

2. Clean and inspect the auto-

density calibration sensor. Test the sensor using the printer’s built-in diagnostics.

3. Replace the image processor.

4. Replace the engine control

board.

5. Replace the carousel home

sensor.

3041-56

3041-57

Variations in glossiness in solid ﬁlls may occur near the oil roll cartridge end of life or with printers running excessively high daily print volumes. If the customer is consistently running a high volume of prints per day, they should user the high-capacity fuser roll cartridge.

1. An oil stain may occur on ﬁrst print after the printer has been idle for an

extended period. If the problem persists on sucessive prints, replace the oil roll cartridge. Look for excessive oil around the fuser.

2. Check the media in the tray. Try new media.

3. Glossiness variations in solid ﬁlls may occur near the oil roll cartridge end

of life or with printers running high daily print volumes. On coated paper, a variation in glossiness may occur 118 mm from the print’s leading edge.

Service Guide 61

Random spotting

There are spots of toner randomly scattered across the page.

1. Slide the paper feeder out of

the printer and inspect the top of the registration chute assembly. Is the top of the registration chute assembly free of toner? If not, remove and inspect the waste toner cartridge. Make sure the cartridge is not damaged or leaking.

2. Remove and inspect the

imaging unit. Is the exterior of the imaging unit clean and with no obvious toner leakage? If not, remove and inspect the waste toner

3041-58

3. Turn the carousel frame and inspect the four developer assemblies. Does

cartridge. Make sure the cartridge is not damaged or leaking.

4. Inspect the fuser. Is the fuser free of toner? Clean the fuser, if necessary.

5. Remove and inspect the accumulator belt cleaner assembly. Is the

accumulator belt cleaner assembly clean and with no obvious toner leakage? If not clean or replace the accumulator belt cleaner assembly, if necessary.

6. With the accumulator belt cleaner assembly removed, inspect the

accumulator belt cleaner end of the auger . Is the auger clogged? Clean the printer interior.

7. Remove the rear cover. With the accumulator belt cleaner assembly

removed, watch the auger drive gear as you manually rotate the paper feed motor. Does the fuser drive assembly rotate the auger drive gear? If not, replace the fuser drive assembly.

8. As you manually rotate the paper feed motor place your ﬁnger inside the

auger opening and feel the movement of the auger spring. Does the auger spring rotate when you manually rotate the paper feed motor? If not, replace the auger assembly.

9. Replace the imaging unit.

62 Phaser 780 Color Printer

Media jams and the paper path

Skewed image

The image area is twisted or is not parallel with the sides of the page. The printer neither jams nor displays an error code.

1. Check that the paper tray’s metal hooks (at the corners of the leading

edge of the paper in the tray) are not bent or deformed.

2. Feed paper out of each of the available paper feeders. Does the image

skew when fed out of one tray but not when fed out of the others? If yes, Inspect the paper and tray of the feeder that is skewing to ensure the tray is correctly loaded and the paper is good.

3. Replace the multi-purpose tray pick-up roller or the main tray feed roller .

4. Print a test print and slide the paper feeder out about 10 seconds after

pressing PRINT. Carefully slide the paper feeder out of the printer and inspect the position of the sheet of paper. Is the sheet of paper parallel to the edges of the paper feeder? If not, replace the turn roller assembly.

5. Generate a test print and slide the fuser out of the printer just as the sheet

of paper is moving through the registration rollers. Carefully slide the paper feeder out of the printer and inspect the position of the sheet of paper. Is the sheet of paper parallel to the edges of the paper feeder as it leaves the registration rollers? If no, clean or replace the feeder rubber registration roller.

6. Remove second bias transfer roller. Manually raise and lower the cam

levers at the ends of the second bias transfer roller. Are the cam levers undamaged? When you raise the levers does the second bias transfer roller lower and when you release the levers does the second bias transfer roller raise? Do the cam levers have a strong spring action? If not, r eplace the second bias transfer roller.

Service Guide 63

Damaged prints

The printed page exits the printer either wrinkled, creased, or torn. The printer neither jams nor displays an error code.

The following components are associated with this speciﬁc problem. One or mor e of these components may have failed partially or completely. If you cannot isolate the problem, replace each component listed below, one at a time, until the problem disappears. Check the media settings at the printer driver.

■ Paper feeder (usually appears without toner in creases or wrinkles)

■ Fuser)

■ Accumulator belt (usually appears with toner in creases or wrinkles)

1. Check that the paper tray’s metal hooks (at the corners of the leading

edge of the paper in the tray) are not bent or deformed.

2. Feed paper out of each of the available paper feeders. Is the paper

damaged when fed out of one tray but not when fed out of the others? If so, inspect the tray for damage and check the paper to ensure it is correct.

3. Is the paper damaged when fed out of multi-purpose tray? Inspect the

multi-purpose tray for debris or obviously broken components that could be damaging the paper as it feeds out of the assembly and into the printer.

4. Inspect the paper feeder for debris or broken components?

5. Generate a test print and open the front cover just as the sheet of paper is

moving through the registration rollers (about 1 second after you hear paper feeding start).

6. Carefully slide the paper feeder out of the printer and inspect the sheet of

paper. Is the sheet of paper undamaged as it leaves the registration rollers? If yes, replace the metal registration roller and the rubber registration roller.

7. Generate a test print and open the front cover just before the sheet of

paper reaches the fuser. Open the front cover and inspect the sheet of paper. Is the sheet of paper undamaged as it leaves the second bias transfer roller? If yes, replace the second bias transfer roller.

8. Generate a test print and open the front cover just as the sheet of paper

exits the fuser. Inspect the sheet of paper. Is the sheet of paper damaged as it exits the fuser? If yes, replace the fuser.

9. Generate a test print and open the upper exit cover just as the sheet of

paper reaches exit roller. Inspect the sheet of paper. Is the sheet of paper undamaged as it nears exit roller? If no, clean or replace the lower exit assembly and the upper exit assembly. Is the sheet of paper undamaged until it reaches exit roller? If yes, replace exit roller.

64 Phaser 780 Color Printer

Inoperative lower tray feeder

The lower tray feeder does not work at all, the lower tray feeder does not attempt to feed paper, and the problem is not identiﬁed by a displayed error code.

1. Ensure the printer driver is conﬁgured with the “optional trays”

installed.

2. Try printing using a different application program.

3. Try printing using a different printer driver.

4. Try printing from another computer.

5. Check the wire harness that is running between the paper feeder circuit

board to the engine control board. Ensure the wire harnesses are connected to P/J131 and 132 on the lower feeder circuit interface board

6. Generate test prints from Tray 2, Tray 3, and Tray 4. Does the printer

generate a test print from any of the lower feeder trays? If no, go to Step 10.

7. Remove the lower feeder rear cover.

8. Measure the voltage between P/J133-B5 and frame ground on the lower

feeder circuit board. Is there +5VDC between P/J133-B5 and frame ground on the lower feeder circuit board? If not, verify that +5 VDC on P33-10 the low voltage power supply.

9. Measure the voltage between P/J133-B1 and frame ground and between

P/J133-B2 and frame ground on the lower feeder circuit board. Is there +24VDC between P/J133-B1 and ground and between P/J133-B2 and FG? If not, verify the +24VDC on pins 13 and 14 of the low voltage power supply and the engine control board.

10. Replace the lower tray feeder circuit board.

11. Replace the engine control board.

Power problems

All front panel indicators remain off. The printer does not initialize upon powerup

1. Check to see if the printer is plugged in.

2. Check the power on/off switch.

3. Reset the fuser and the paper feeder.

4. Refer to the topic “Printer will not power up” on page 40.

Service Guide 65

Front panel indications

Media tray indicates missing or empty when it is not

1. If there is media in the tray, then check the media sensors. If the lower

feeder is available, switch trays to verify the source of the problem

2. Check to see if the paper-empty sensor is broken.

3. Run service diagnostics on the media sensors.

4. Check the media selection switch actuators on the rear of the paper tray.

Also check the paper size switches at the rear of the printer frame or the lower feeder.

Macintosh printing problems

Image never prints

Printer acts as if it is receiving data, but nothing comes out of printer or it goes back to “Ready” mode without printing image.

1. Power cycle the printer and print again.

2. Make sure that the correct Phaser 780 printer icon was selected in the

Chooser. Try printing the job again.

3. In the Chooser or the print dialog, switch background printing to off. Try

printing the job again.

4. Ensure that the printer can print by printing an internal front panel test

print.

5. Enable the Error Handler through the front panel and try printing the job

again. If an error page is printed after printing the job again, call the Customer Support Hotline for further assistance. Please have the error page in hand. If available, try printing to a black-and-white PostScript printer (such as an Apple LaserWriter). If the ﬁle does not print on the black-and-white PostScript printer, this may mean that the problem may be application- or network-related.

Image prints in black-and-white

1. In the print driver dialog box, make sure the Color/Grayscale option has

been selected.

2. Check the version of your LaserWriter driver to ensure that it is version

6.0.7 or higher. Earlier versions of the driver do not support color PostScript. The application may require special instructions to print.

3. Ensure the driver setting TekColor is not set to Monochrome mode.

66 Phaser 780 Color Printer

Image is rotated 90 degrees

1. In the application's Page Setup, make sure that the image is selected to

print in portrait or landscape orientation to match the document. Also ensure the selected paper size is correct.

2. Ensure that the printer can print by printing an internal front panel test

print.

3. Enable the Error Handler through the front panel and try printing the job

again. If an error page is printed after printing the job again, call the Customer Support Hotline for further assistance. Please have the error page in hand. If available, try printing to a black-and-white PostScript printer (such as an Apple LaserWriter). If the ﬁle does not print on the black-and-white PostScript printer , this may mean that the pr oblem may be application- or network-related.

Windows printing problems

Image never prints

Printer acts as if it is receiving data, but nothing comes out of printer or the printer goes back to “Ready” mode with out printing image.

1. Under the printer's setup options, set RETRY = 850

2. Try printing from the printer driver.

3. Try printing from another application.

4. Try printing to another printer.

5. Try printing from another computer.

6. Try printing an internal front panel test print.

Blue color on the screen is printing too purple.

Many applications describe color as percentages of a video display screen’s primary colors: red, green, and blue (RGB). When a printer translates these RGB colors into its own primaries of cyan, magenta, and yellow (CMY), blue is often printed as purple.

1. To adjust blue from within Microsoft Windows: Within the Tektronix

PostScript Windows driver you have an option, Vivid Color, that alters to blue colors that are appearing purple.

To Access this option, select:

Printer Control Panel

Right click Printer Driver Choose Properties Choose Color Corrections Select Vivid Color

Service Guide 67

Printing from Windows 3.1 produces the message “Problem writing device LPT1: Cancel or Retry”.

Option #1:

1. Select Printers, and click Conﬁgure.

2. Change the port selection from LPT1 to LPT1.OS2.

3. The MODE command disables DOS timeouts. The LPT1.OS2 selection

forces Windows to print through DOS instead of directly to the printer.

Option #2: The solution above does not allow users to spool documents using the PrintManager. To use the PrintManager as well as correcting time-out problems, edit the following line in the win.ini ﬁle:

TransmissionRetryTimeout=45 to: TransmissionRetryTimeout=850

In Windows 3.1:

1. Follow the above instructions for issuing the MODE command in DOS.

2. Start Windows.

3. Select the Control Panel from the Main menu.

4. Select Printers

5. Select the appropriate printer and click on Connect.

6. Uncheck the Fast Printing Direct to Port box.

Workstation printing problems

Image never prints

Printer acts as if it is receiving data, but nothing comes out of the printer or the printer goes back to “Ready” mode without printing an image.

For serial or parallel printing. Ensure that the print ﬁle ends with a “CTRL-D” character. CTRL-D indicates the end-of-ﬁle, which the printer responds to by closing host-to-printer communications and then processing and printing the ﬁle. Use a text editor to open and examine the ﬁle. There is a utility ﬁle that you can use to tag or remove a CTRL-D to the end of a print ﬁle. TCP/IP and Novell protocols do not accept CTRL-D with the print ﬁles. Refer to the network user manual.

68 Phaser 780 Color Printer

Running built-in diagnostics

The printer diagnostic interface consists of a front panel containing a 2 line by 40 character LCD display and six buttons. For diagnostics, the front panel switches are identiﬁed as 1 through 6 with switch 1 being the left-most switch and switch 6 being the right-most switch.

To place the printer in service diagnostics mode. Turn on the printer and wait for a

string of “ button 3 for ﬁve seconds. You select individual test by navigating a tree-structure with three buttons deﬁned as Prev, Next, and Select.

Help Mode. You can enter a Help mode at the top level by pressing Prev or Nest

until Help Mode On/Off is displayed. Once you select Help mode and “H” is displayed on the lower-right corner of the display. With help mode enabled, once you select a test, information about the test is displayed in the top line of the display. Buttons 3 and 4 are relabeled as Quit and More. Pressing More displays additional information about the test. Pressing Quit leaves the test description and asks if you want to run the test.

Table 1 Diagnostic tests

Test Sub-tests Detail

Service Print Source Tray 1

” to appear on the front panel display, as they appear, press and hold

Tray 2 Tray 3 Tray 4

Output Right Side

Media Paper

Print Black Grid

Paper Path Test

Image Processor Kernel, DIMMs, ROMs,

I/O

Engine ROM Revision

MPT

Top Cover

Transparency Label Cover

Color Grid Black Patch Color Patch

Service Guide 69

Table 1 Diagnostic tests

Test Sub-tests Detail

Sensors Belt Home Sensor

Carousel Home Sensor Waste Cartridge Sensor Waste Cartridge Full

Sensor Full Stack Sensor Exit Sensor New Toner Sensor Toner Cartridge Present

Sensor Paper Feeder Interlock MPT Long Paper Sense MPT Paper Sensor MPT Edge Sensor Registration Sensor Oil Roller Switch New Oil Roller Switch Fuser Interlock Switch Fuser Entry Sensor Fuser Exit Sensor Front Cover Interlock Lower Feeder Interlock T r ay 1 Present Indicates Missing or Size Tray 2 Present Tray 3 Present Tray 4 Present

70 Phaser 780 Color Printer

of media selection

Table 1 Diagnostic tests

Test Sub-tests Detail

Sensors (cont.) Tray 1 Low Sensor

Tray 1 Empty Tray 2 Low Sensor Tray 2 Empty Tray 3 Low Sensor Tray 3 Empty Tray 4 Low Sensor Tray 4 Empty Auto-density Calibration

Sensor

Motors/Solenoids Process Motor Slow/Fast

Paper Feed Motor On/Off Laser Motor On/Off Toner Dispense Motor One Time Lower Feeder Motor On/Off MPT Feed Clutch MPT Pick Solenoid MPT Pre-Registration

Clutch MPT Registration Clutch Developer Clutch Second Bias Transfer

Clutch Oil Roller Solenoid Belt Cleaner Solenoid

Pass/Fail test of sensor and its wiper solenoid; for solenoid portion of test, listen for clicks of sensor wiper solenoid.

Tray 2 Pick Solenoid Tray 3 Pick Solenoid Tray 4 Pick Solenoid Tray 2 Feed Clutch

Service Guide 71

Table 1 Diagnostic tests

Test Sub-tests Detail

Motor/Solenoids (cont.) Tray 3 Feed Clutch

Tray 4 Feed Clutch Rear Fan Slow/Fast Speed Fuser Fan Slow/Fast Speed Erase lamp On/Off Fuser Lamp (heater) On/Off

Front Panel Front Panel Display

Front Panel LEDs

Life Data Save Life Count The Save function copies

Restore Life Count

Drum Unit Life Yellow T oner Life Magenta T oner Life Black Toner Life Cyan Toner Life Printer Life Bias Transfer Roller Life Belt Cleaner Life

all consumable and FRU counts from the engine control board NVRAM to the image processor board. The Restore function returns the values to the engine control board NVRAM. The Save function must be performed prior to replacing the engine control board. Perform the Restore function after the replacement

Fuser Oil Life Fuser Unit Life Reset Fuser Life Perform the appropriate Reset Bias Transfer

Roller Life Reset Belt Cleaner Life

72 Phaser 780 Color Printer

reset function whenever one of these FRUs is replaced to return that FRUs copy count to zero

Adjustments

This topic discusses using the front panel’s interactive mode to review and change the printer’s operation. It also contains the procedures to calibrate the printer after you replace key Field Replaceable Units and to evaluate the printer's functionality.

Printing test prints

The prints printed via the front panel the are generated by the image processor. While the printer is idle you can use the front panel to print an image stor ed in the image processor such as the conﬁguration page.

Print service test prints

The service prints allow you to evaluate the printer’s print quality.

Press the

Select the

Scroll to either

Printing the conﬁguration page

Printer Menu Select

Help Pages.

Service Print 1

button.

Service Print 2

and press

The conﬁguration page shows a great deal of information regarding the data and set-up values stored in NVRAM. In the same Help pages menu you can also print the startup page.

Press the

With the

Page

Printer Menu Select

Help pages

menu item. Press

menu displayed, scroll to the

button.

Configuration

Printing the demonstration pages

Demo pages demonstrate the capabilities of the printer.

Press the

With the

Page

Printer Menu Select

Help pages

item. Press

button.

menu displayed, scroll to the

Service Guide

Demonstration

Print engine calibration

Generally, only one print engine calibration is required. Usually, if you note a print defect, replacing a toner cartridge, a developer or the imaging unit or perhaps the paper feeder corrects the problem.

Adjusting for impulse banding

Impulse banding is a print artifact that occurs on prints when the developer roller comes into contact with the drum. This adjustment adds shims to the carousel assembly to slightly alter the position of each developer assembly relative to the drum.

Note

Ensure the printer is in a ready-to-operate condition.

Turn off the printer.

Remove the top cover.

With a pen or marker (no pencil), scribe a line across the white tracking roller located at the front of the developer roller.

Position the white roller so the mark is even with the edge of the nearly developer frame.

Hold the carousel lock so it will not impede the carousel’s movement.

With a slow, smooth action, rotate the carousel assembly 180o. Do not allow the carousel to stop as the developer pass the drum surface. Continue rotating the carousel to bring the marked developer to its starting position.

As the developer roller contacts and passes the drum surface, the developer should rotate about 2 mm. Too much rotation, caused by the roller contacting the drum too soon, causes impulse banding.

Inspect the white tracking roller for movement. If the mark is within 2 mm of its original position, no adjustment is needed.

The shims used in this adjustment permanently clip into place and can be difﬁcult to remove. You should modify a set of shims by cutting the clips off of the shims so they can be inserted and removed easily. Once you determine the correct shims required, install permanent shims in their place.

If the mark is rotated beyond 2 mm, a shim is required.

Generally, a 1 mm shim usually corrects impulse banding. Install a shim in the side of the carousel assembly for the developer being tested.

10.

Repeat the procedure from Step 5 until the rotation is about 2 mm. If rotation is not enough, use a smaller shim. Too much, use a larger shim.

11.

Repeat for each developer.

Phaser 780 Color Printer

Developer roller

Place mark on white roller

After carousel rotation mark should move 2mm

Install shim

Lift up slightly to install shim

Adjusting for impulse banding

Service Guide

3041-32

Phaser 780 Color Printer

Cleaning and Maintenance

Service preventive maintenance procedure

Whenever you check, service, or repair a printer, you should perform the following procedures. Cleaning the printer, as outlined in the following steps, assures proper operation of the printer and reduces the probability of having to service the printer in the future.

The frequency of use and the type of paper a customer prints on will, in large part, determine how critical cleaning the machine is. Users of ordinary Bond paper (copier paper) should have very few problems since this paper is smooth and relatively dustfree. You should thoroughly inspect and clean these printers.

Ask each printer customer about the type of paper he or she uses so that you can be sure to clean the parts of the printer that particular paper may affect. If a customer is printing on the more unusual or dustier papers, then you should pay particular attention to these printer parts:

■

The standard pick roller

■

The multi-purpose pick roller

■

The feed rollers

■

The cabinet interior

■

The exit rollers

Recommended tools

■

Toner vacuum cleaner

■

Suction bulb (air blower)

■

Cleaning water

■

Lint-free wipes

■

Cotton swabs

■

Imaging unit cover

■

Isopropyl alcohol (greater than 90% pure)

Service Guide

Cleaning

Caution

Turn off the printer.

Remove the imaging unit and cover it to protect it from the light.

Remove the toner cartridges.

Slide out the fuser.

Remove the paper tray.

Slide out the paper feeder.

Clean all printer rollers, except the second bias transfer roller and the fuser rollers, with alcohol-dampened wipes only.

Clean the laser window with puffs of air from the suction bulb. Alternately, you can vacuum the window clean.

Wipe off the pre-exposure erase lamp with a lint-free wipe.

10.

Vacuum out the interior of the printer.

11.

Vacuum loose toner out of the carousel assembly.

12.

Remove and clean the accumulator belt cleaner assembly. Removing the accumulator belt cleaner assembly is explained on the

Service CD-ROM

using a vacuum with a brush attachment. Do not touch the cleaner blade with your hands nor bend or crease the ﬁlm seal.

Never

apply alcohol on the second bias transfer roller.

Never

apply alcohol to the fuser rollers.

. Once removed, gently vacuum the cleaner assembly

Phaser 780

13.

If you must clean the fuser rollers, clean the fuser rollers by processing 10 sheets of paper through the printer. If more cleaning is needed, clean the rollers with a soft, lintfree cloth with either fuser oil or water.

Phaser 780 Color Printer

never

clean them with alcohol. First

Resetting NVRAM

Resetting NVRAM returns all the image processor's NVRAM-stored parameters to their factory defaults except the print counts and the Adobe ﬁrmware serial number.

Caution

To reset the image processor to its factory default values, follow this procedure:

Turn on the printer

When the row of “*”, begins to be displayed on the front panel, press and release button 1 and then press and release button 4.

When the front panel displays “ then press and release button 3. The display r esponds with the message “ normally.

Resetting NVRAM will also reset the network card’s NVRAM. If possible, copy down all network parameters or print the Conﬁguration Page.

Resetting NVRAM

Password?

.” Following NVRAM reset, the print powers up

”, press and release button 1,

Service Guide

Phaser 780 Color Printer

Key FRU Disassembly

This topic illustrates how to remove and replace key printer Field Replaceable Units (FRUs). Refer to the later topic “FRU List” on page 137 for a list of the printer’s FRUs. For more detailed removal/replacement procedures refer to the

Phaser 780 Service CD-ROM

Service Guide

Paper feeder

Slide the paper feeder far enough out of the printer so you can reach the assembly rails.

Push in on the front rail latch as you slide the front of the paper feeder out far enough to disengage the latch.

Push in on the rear rail latch as you slide the rear of the paper feeder out far enough to disengage the latch.

Slide the paper feeder out of the printer.

Reverse these steps to install the paper feeder.

Rear latch

Removing the paper feeder

Phaser 780 Color Printer

Front latch

780-5-34

Feeder registration chute

Slide the paper feeder out of the printer. You do not need to remove the paper feeder.

Remove the E-ring securing the rear arm of the registration chute to the paper feeder.

Remove the screw securing the ground wire to the chute. Remove the wire.

Open the registration chute.

Slide the chute to the rear and remove the chute.

Reverse these step to install the registration chute.

Registration chute

Ground wire

Removing the registration chute

Service Guide

780-5-37

Feeder registration clutch

Remove the paper feeder as described in “Paper feeder” on page 82.

Turn over the paper feeder and disconnect the wiring harness from the registration clutch.

Open the registration chute.

Remove the E-ring securing the registration clutch to the rear of the metal registration roller. Remove the registration clutch from the roller.

Reverse these steps to install the registration clutch.

Registration clutch

Removing the registration clutch

Phaser 780 Color Printer

Wiring harness

780-5-40

Registration brake clutch

Remove the paper feeder as described in “Paper feeder” on page 82.

Turn the paper feeder over and disconnect the wiring harness from the registration brake clutch.

Remove the three screws securing the registration brake clutch assembly to the side of the paper feeder. Remove the assembly.

Remove the E-ring securing the registration brake clutch to the clutch shaft and remove the clutch.

Remove the E-ring securing the registration brake gear to the gear shaft. Remove the gear.

Reverse these steps to install the registration brake clutch.

Wiring harness

Registration brake assembly

Registration brake clutch

Removing the registration brake clutch

Registration brake gear

Service Guide

780-5-46

Feeder metal registration roller

Remove the feeder registration clutch as described in “Feeder registration chute” on page 83.

Remove the registration brake clutch as described in “Registration brake clutch” on page 85.

Remove the E-ring securing the out gear at the front end of the metal registration roller. Remove the gear.

Remove the rear bearing from the metal registration roller.

Slide the metal registration roller to the rear, slide the front of the roller out of the front bearing, and remove the roller from the main paper feeder.

Reverse these steps to install the feeder metal registration roller.

Metal registration roller

Rear bearing

Front bearing

Out gear

Removing the metal registration roller

Phaser 780 Color Printer

780-5-41

Tektronix Phaser 780 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual