Oki MC760 User manual

OEL Maintenance Manual
MC760/MC770/MC780
ES7470MFP/ES7480MFP
Revision2
This document is “OKI DATA – CONFIDENTIAL”
Only persons and parties authorised by OKI DATA have
permissions to access this document.
This document should not be accessed by any parties
without the approval of OKI DATA.
Anyone who is found to be contradicting the above may be subject to legal action.

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Document Revision History
Rev.No Date
Corrected items Person in
charge
No. Page Description of change
1 2013-03-28 Issue P2E1 T. Asaba
2 2013-09-10 Add LCF Unit P2E16 T.Oyama
3 2013-12-24 Correct error codes P2E16 T.Oyama
4 2015-07-17 Correct remedial measure PBPE12 S.Hirose
5 2015-09-15 Correct remedial measure PBPE12 S.Hirose
6 2015-10-15 Add 4.2.34, 4.2.35 PBPD21 H. Ueda
7 2015-11-25 Correct remedial measure PBPE12 S.Hirose
8 2016-07-15 Add REG ADJUST TEST PBPE12 S.Hirose
9 2017-08-11 Drawing update for 5.1 SE43 Y. Utsubo
10 2017-10-20 Correct description
contents
HC21 H.Eguchi
11 2019-01-31 Error correction HM22 I.Kitano
12 2019-04-23 85 Addition of parts HD12 H. Ueda
Rev.No Date
Corrected items Person in
charge
No. Page Description of change

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This manual provides an overview of method for maintaining the MC760/MC770/MC780.
This manual is intended for maintenance staff. For more information about how to operate
the MC760/MC770/MC780, please refer to User 's manual.
Note! • Manual may be revised and updated at any time without notice.
• Unexpected mistakes may exist in the manual.
OKI will not assume any responsibility whatsoever for damage to the
equipmentrepaired/adjusted/changed by the user etc with this manual.
• The parts used for this printer may be damaged when handling
inappropriately. We strongly recommend maintaining this machine by our
registration maintenance staff.
• Please operate the machine after removing static electricity.
PREFACE
Risk of explosion if battery is replaced by an incorrect type.
Battery of the printer need not to be replaced. Do not touch the
battery.
Replace the whole board to replace the CU board.
In the case of replacing batteries at board repairs, replace with the
specified type ones. Installation of another type batteries may result in
explosion.
Caution for used batteries are as follows; do not recharge, force open,
heat or dispose of in fire.

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Index
1. Configuration...........................................................................6
1.1 System configuration ............................................................................................ 7
1.2 The Configuration of printer.................................................................................. 8
1.3 Optional parts ....................................................................................................... 9
1.4 Specifications ..................................................................................................... 10
1.5 Specification of interface .................................................................................... 18
1.5.1 Specification of USB interface .................................................................... 18
1.5.1.1 General of USB interface..................................................................... 18
1.5.1.2 Connector and cable of USB interface................................................. 18
1.5.1.3 USB interface signal ............................................................................ 18
1.5.2 Specification of network interface ............................................................... 19
1.5.2.1 General of network interface................................................................ 19
1.5.2.2 Connector and cable of network interface ........................................... 19
1.5.2.3 Signal of network interface .................................................................. 19
1.5.3 Telephone Line Interface Specification ....................................................... 20
1.5.3.1 Outline of telephone Line Interface...................................................... 20
1.5.3.2 Telephone Line Interface Connector and Cable................................... 20
1.5.3.3 Telephone Line Interface signal ........................................................... 20
1.5.4 USB Host Interface ..................................................................................... 20
1.5.4.1 Outline of USB Host Interface.............................................................. 20
1.5.4.2 USB Host Interface Connector ............................................................ 20
1.5.4.3 USB Host Interface Signal ................................................................... 20
1.5.5 Specification of ACC interface .................................................................... 21
2. Operating instructions..........................................................22
2.1 Electrophotographic processing mechanism...................................................... 23
2.2 Printing process.................................................................................................. 27
2.3 Image Scanning process.................................................................................... 38
2.3.1 Structure and process of RADF.................................................................. 38
2.3.1.1 Cross-section view............................................................................... 38
2.3.1.2 Electrical configuration......................................................................... 38
2.3.1.3 Fundamental operations ...................................................................... 39
2.3.1.4 Document detection............................................................................. 42
2.3.1.5 Jam detection ...................................................................................... 43
2.3.2 Document table structure............................................................................ 43
2.3.2.1 Overview.............................................................................................. 43
2.3.2.2 Exposure block .................................................................................... 44
2.3.2.3 Carraige-Assy drive mechanism.......................................................... 44
3. Set up .....................................................................................45
3.1 Notes and precautions........................................................................................ 46
3.2 Unpack method .................................................................................................. 47
3.3 Setting method ................................................................................................... 48
3.4 List of equipments and accessories ................................................................... 49
3.5 Assembling method ............................................................................................ 50
3.5.1 Assemble the main body of the MFP.......................................................... 50
3.5.2 Cable connect ............................................................................................. 57
3.5.3 Optional part installation and confirmation.................................................. 59
3.6 Setting content print (Configuration)................................................................... 64
3.7 Connecting method ............................................................................................ 65
3.8 User used Paper confirmation ............................................................................ 69
4. Component replacement ...................................................... 70
4.1 Precautions on component replacement............................................................ 71
4.2 Method of component replacement.................................................................... 73
4.2.1 Belt unit....................................................................................................... 73
4.2.2 Fuser unit.................................................................................................... 74
4.2.3 Right side cover .......................................................................................... 74
4.2.4 Left side cover............................................................................................. 75
4.2.5 Scanner unit ............................................................................................... 75
4.2.6 Faceup tray ................................................................................................ 76
4.2.7 Rear cover................................................................................................... 76
4.2.8 LED Assy/ LED Assy spring........................................................................ 77
4.2.9 CU/PU PCB/Low voltage power supply ...................................................... 77
4.2.10 Stay-R ......................................................................................................... 79
4.2.11 Plate-Board-R Assy/Guide-Cable Power Low............................................. 79
4.2.12 Top cover Assy............................................................................................ 80
4.2.13 Top cover .................................................................................................... 81
4.2.14 Frame Assy Top Front................................................................................. 81
4.2.15 Board MFH ................................................................................................. 82
4.2.16 Hopping motor/ Fuse motor........................................................................ 83

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4.2.17 Guide eject Assy/ Color regist Assy/ Board-IBY ......................................... 84
4.2.18 FAN(Fuser) / Belt motor/ High-voltage board / Lever Assy.-InterLock /
Cover open switch....................................................................................... 85
4.2.19 MPT Assy ................................................................................................... 85
4.2.20 Cover Assy front/ Board-RSF/MPT hopping roller/ Frame Assy separator/
Feeder Assy regist...................................................................................... 86
4.2.21 Plate-Driver/ Shaft-Liftup/ Hopping cover.................................................... 87
4.2.22 Plate-Assy-Side R/ Plate-Assy-Side L........................................................ 88
4.2.23 Feed roller................................................................................................... 88
4.2.24 Eject sensor/Micro-SW ............................................................................... 89
4.2.25 Antenna (for wireless model only)............................................................... 89
4.2.26 Finisher (MC780dnf only)............................................................................ 90
4.2.27 Stapler (MC780dn only).............................................................................. 91
4.2.28 Tray-Assy-Document/Cover-ADF-R............................................................ 92
4.2.29 ADF-unit ..................................................................................................... 93
4.2.30 Sheet-document / Paper-weight-Assy / Spring-PW-ADF............................94
4.2.31 Hinge-Assy-L / Hinge-Assy-R ..................................................................... 95
4.2.32 ADF-Assy ................................................................................................... 95
4.2.33 Guide-Retard / Roller / Motor / Clutch / Solenoid / Photo-sensor............... 96
4.2.34 Cover-Assy-Top-ADF.................................................................................. 97
4.2.35 Frame-Assy-Hopping-ADF ......................................................................... 98
4.2.36 Guide-Assy-Retard ..................................................................................... 99
4.2.37 Flatbed-Unit ................................................................................................ 99
4.2.38 Frame-assy-FB ......................................................................................... 100
4.3 Check the Scanner Mech Level and SU FW version........................................ 101
4.4 Oiling spots....................................................................................................... 102
5. Maintenance Menu .............................................................. 113
5.1 Maintenance Utility .......................................................................................... 114
5.2 Maintenance menu functions............................................................................ 115
5.2.1 Self-diagnostic mode ................................................................................ 115
5.2.1.1 Operation panel ................................................................................. 115
5.2.1.2 Ordinary self-diagnostic mode (level 1) ............................................. 117
5.2.1.3 Switch scan test................................................................................. 118
5.2.1.4 Motor clutch test ................................................................................ 120
5.2.1.5 Test print ............................................................................................ 122
5.2.1.6 Color registration correction test........................................................ 126
5.2.1.7 Density correction test ....................................................................... 127
5.2.1.8 Consumable item counter display...................................................... 129
5.2.1.9 Number of print copies counter display ............................................. 130
5.2.1.10 Switching between the Factory mode and the Shipping mode.......... 130
5.2.1.11 Self-diagnostic function setting .......................................................... 131
5.2.1.12 LED head serial number display ....................................................... 132
5.2.1.13 NVRAM parameter setting ................................................................ 132
5.2.2 How to enter the Scanner Maintenance Menu.......................................... 133
5.3 Setups upon completion of part replacement................................................... 135
5.3.1 Precautions when replacing the PU board................................................ 135
5.4 Density control manual setting ......................................................................... 137
6. Periodic Maintenance.......................................................... 138
6.1 Cleaning ........................................................................................................... 139
6.2 How to clean the LED lens array ...................................................................... 140
6.3 How to clean the pickup roller .......................................................................... 142
6.4 How to clean the paper feed rollers for MP Tray ............................................... 143
6.5 How to clean the rollers in the ADF.................................................................. 144
6.6 How to clean the document rollers in the ADF ................................................. 145
6.7 How to clean the document glass..................................................................... 146
6.8 How to clean inside of MFP.............................................................................. 147
7. Troubleshooting and repair procedure ............................. 149
7.1 Before starting the repair work ......................................................................... 150
7.2 Confirmation items before taking corrective action against abnormalities ....... 150
7.3 Precautions when taking corrective action against abnormality ....................... 150
7.4 Preparation for troubleshooting ........................................................................ 150
7.5 Troubleshooting method ................................................................................... 151
7.5.1 Error code list............................................................................................ 151
7.5.2 Printer error troubleshooting ..................................................................... 154
7.5.3 Scanner error troubleshooting .................................................................. 160
7.5.4 Preparation for troubleshooting................................................................. 162
7.5.5 Troubleshooting the abnormal images ...................................................... 199
7.6 Fuse check ....................................................................................................... 206
7.7 Paper cassette switches versus Paper size correspondence table .................. 207
8. Connection diagrams..........................................................208
8.1 Resistance value check.................................................................................... 209
8.2 Parts location.................................................................................................... 214

1.
Configuration
1.1 System configuration .....................................................................7
1.2 The Configuration of printer...........................................................8
1.3 Optional parts ................................................................................9
1.4 Specifications ..............................................................................10
1.5 Specification of interface..............................................................18

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1.Configuration
FAX Control PCB
FAX LINE PCB
OPE
WLAN
Antenna
DIMM
HDD
HOST
USB
(Front)
HAND
SET
LCD Speaker
RFID PCB
Finisher Unit
Stapler
CM_ID
Motor
YK_ID
Motor
Stapler Cover SW
K LED HEAD
Y LED HEAD
M LED HEAD
C LED HEAD
Stacker
full
sensor
ID
FAN
M
HEAT
Low-voltage PCB
Toner sensor PCB
Environment sensor PCB
Front sensor PCB
(WR,IN1,IN2)
Hopping
clutch
MPT
clutch
Regist
clutch
1st
P. E
sensor
HOP
sensor
M
ID UP
M
BELT
Paper
size
SW
M
HOP
Duplex
FANFront
sensor
IN
sensor
Cover
open
sensor
Bottom
sensor
DUPLEX PCB
Duplex
clutch
Duplex
motor
Separator
solenoid
Feed
clutch
Hopping
clutch
Paper-feeding/
moving motor
2nd
P. E
sensor
2nd
IN
sensor
2nd
paper
size SW
2nd TRAY PCB
2nd
hopping
sensor
Inlet
AC-SW
Inter Lock SW
High-voltage PCB
Fuser
FAN
Fuser
Low-voltage
FAN
FAX
TEL
USB
HOST
USB
LAN
Unit-CIS
FB
Motor
Rear Cover SW
Relay PCB
EXIT
sensor
Density
sensor
Color blur PCB
right
Color blur PCB
left
Belt unit
Fuser
3rd
P. E
sensor
3rd
IN
sensor
3rd
paper
size SW
3rd
hopping
sensor
3rd TRAY PCB
Scan
sensor
HOP
sensor
Regist
sensor Reverse
sensor
Paper
Set
sensor
M
ADF
Cover
Open
sensor
solenoid Clutch
Clutch
FB
Home Position sensor
Feed
clutch
Hopping
clutch
Paper-feeding/
moving motor
4th
P. E
sensor
4th
IN
sensor
4th
paper
size SW
4th
hopping
sensor
4th TRAY PCB
Feed
clutch
Hopping
clutch
Paper-feeding/
moving motor
PU PCB
ADF Relay PCB
CU PCB
SU PCB
Option
Feed
clutch
Hopping
clutch
M
LIFT
Paper-feeding/
moving motor
P. E
sensor
IN
sensor paper
size SW
LCF PCB
hopping
sensor
Option
Option Option
FAX部
IC Card Reader
KP-2006(Felica)
KP-2004(HID)
KP-2005(Mifare)
Option
Fig1-1
1.1 System configuration
Figure 1-1 represents the system configuration of the printer.

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1.Configuration
Fig 1-2
1.2 The Configuration of printer
The parts in the MC760/MC770/MC780 are shown as below.
• Electrophotography process mechanism
• Paper feed path
• Control part (CU part/ PU part/ FAX Unit)
• Operator panel
• Power part (High-voltage part/low-voltage part)
The Configuration of the MFP is shown in Fig 1-2.

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1. Configuration
1.3 Optional parts
The optional parts for this printer are shown as below.
(1) Optional tray(second tray/ third tray/fourth tray*)
*fourth tray:not support for Finisher model
(2) Spacer
(3) Caster Stand
(4) LCF

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1. Configuration
1.4 Specifications
Fundamental specifications
Category Item MC760 MC770 MC780
Outside dimensions Width 522mm
Depth 604mm
Height 675mm (Finisher model:811mm)
Weight Approx. 50kg (Finisher model:60kg)
CPU CU APM86190
RAM CU Resident 2 GB
Option N/A
ROM CU Program 8MB
Control Panel LCD 9 inch WVGA color touch panel
Size:198.0 mm(W) x 111.7 mm(H)
Resolution:800dot x 480dot
Hard Keys Ten key, start key, stop key, power key,
ENERGY SAVER KEY and others
Qwerty keyboard No
Operation sound Operating
55dB(A)
(Sound pressure level)
57dB(A)
(Sound
pressure
level)
Standby 37dB(A) (Sound pressure level)
Power save mode Inaudible
Power consumption Power input 110-127VAC (Range 99-140VAC)
220-240VAC (Range 198-264VAC)
Sleep mode 1.5W (no FAX model)
2.0W (FAX model)
Power save mode 60W
Idle 130W
Typical operation 800W
Peak 1500W
Category Item MC760 MC770 MC780
Operating environment
(temperature)
During operation 10 °C to 32 °C,17 °C to 27 °C (Full color
print quality assurance temperature)
During non-operation 0°C - 43°C, Power OFF
During storage
(Maximum one year)
-10°C to 43°C, with drum and toners
During transportation
(Maximum one month)
-30°C - 50°C, with drum, without toners
During transportation
(Maximum one month)
-30°C to 50°C, with drum and toners
Operating environment
(humidity)
During operation 20% - 80%, 50% - 70% (Full color print
quality assurance humidity), Maximum
wet-bulb temperature 25°C
During non-operation 10% - 90%, Maximum wet-bulb
temperature 26.8°C, power OFF
During storage 10% - 90%, Maximum wet-bulb
temperature 35°C
During transportation 10% - 90%, Maximum wet-bulb
temperature 40°C
Emulation Standard PCL5e/PCL5c/PCL6/PS3 emulation/
PDF emulation/XPS
Emulation switch Automatic
Others USB-IF logo Yes
Windows logo Yes
Operations on UPS Operations on UPS (uninterruptible
power supply) are not guaranteed.
Do not use UPS.
CPU SU Core ARM9
RAM SU Resident 256 MB
Option None
ROM SU Program 4MB