Oki OKIPAGE 8c Plus User manual

41057601TH Rev.1 1 / 199
OKIPAGE 8c Plus
/ OKICOLOR 8
Color LED Page Printer
MAINTENANCE
MANUAL
ODA/OEL/INT
1999.8.12 Rev.1

41057601TH Rev.1 2 /
Rev.No. Date Corrected items Person in
No. Page Description of change change
1 1999.8.12 ISSUE E4 Yamazaki

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PREFACE
Thismaintenancemanualprovidesproceduresandtechniquesforthetroubleshooting,maintenance,and
repair of OKICOLOR 8 / OKIPAGE 8c Plus.
This manual is written for maintenance personnel, but it should always be accompanied with the
OKICOLOR 8 / OKIPAGE 8c Plus User’s Manual for procedures for handling and operating OKICOLOR
8 / OKIPAGE 8c Plus. For repairing each component of OKICOLOR 8 / OKIPAGE 8c Plus, see the
Troubleshooting manual.
[Notices]
The contents of this manual are subject to change without prior notice.
Althoughreasonableeffortshavebeentakeninthepreparationofthismanualtoassureitsaccuracy,this
manual may still contain some errors and omissions. OKI will not be liable for any damage caused or
alleged to be caused, by the customer or any other person using this maintenance manual to repair,
modify, or alter OKICOLOR 8 / OKIPAGE 8c Plus in any manner.
[Warning]
ManypartsofOKICOLOR8/OKIPAGE8cPlusareverysensitiveandcanbeeasilydamagedbyimproper
servicing. We strongly suggest that OKICOLOR 8 / OKIPAGE 8c Plus be serviced by OKI’s authorized
technical service engineers.

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CONTENTS
1. SPECIFICATIONS ............................................................................................ 7
1.1 Basic System Configuration............................................................................................. 7
1.2 Printer Specifications .......................................................................................................8
1.3 Option Specifications ....................................................................................................... 9
1.4 Basic Specifications....................................................................................................... 10
2. OPERATION...................................................................................................12
2.1 Main Control Board (PCE PCB)..................................................................................... 13
2.2 Engine Control Board (PX4 PCB) .................................................................................. 16
2.3 Power/Units.................................................................................................................... 17
2.4 Mechanical Processes................................................................................................... 18
2.4.1 Electrophotographic processing mechanism .................................................... 19
2.4.2 Paper running process ..................................................................................... 25
2.5 Sensors.......................................................................................................................... 34
2.5.1 Paper related sensors ...................................................................................... 34
2.5.2 Other sensors ................................................................................................... 35
2.6 Correction of Color Deviation......................................................................................... 36
2.7 Transfer Control according to Environmental Changes
(Room Temperatures and Relative Humidities)............................................................. 36
2.8 Form Jam Detection....................................................................................................... 37
2.9 Cover Opening............................................................................................................... 37
2.10 Toner Low Detection...................................................................................................... 38
2.11 Page Size Detection ...................................................................................................... 39
2.12 Power-on Processing..................................................................................................... 40
2.12.1 Self-diagnostic test ........................................................................................... 40
3. PARTS REPLACEMENT................................................................................41
3.1 Precautions for Parts Replacement ............................................................................... 41
3.2 Parts Layout................................................................................................................... 43
3.3 How to Change Parts..................................................................................................... 47
3.3.1 Cover Assy Rear .............................................................................................. 48
3.3.2 Motor-Fan (80-25) ............................................................................................ 49
3.3.3 Paper Eject Assy .............................................................................................. 50
3.3.4 Cover Assy Stacker, Guide Eject FD Assy....................................................... 51
3.3.5 Frame Assy Upper............................................................................................ 52
3.3.6 Plate Support Assy ........................................................................................... 53
3.3.7 Limiter 2way (L), (R) / Plate Guide (L) , (R) ...................................................... 54
3.3.8 Cover ............................................................................................................... 55
3.3.9 PCB Assy : PCE ............................................................................................... 56
3.3.10 Motor Fan (CU)................................................................................................. 57
3.3.11 PXF PCB/PX4 PCB .......................................................................................... 58
3.3.12 Gear Heat Assy ................................................................................................ 59
3.3.13 Main Motor (A), (B) Assy .................................................................................. 60
3.3.14 Gear One-way (Z30)......................................................................................... 61
3.3.15 Motor Assy BT .................................................................................................. 62
3.3.16 Power Supply Unit, Holder Inlet, Sheet Insulation............................................ 63
3.3.17 Sensor Assy Box Toner .................................................................................... 64
3.3.18 Square-shaped Connector ............................................................................... 65

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3.3.19 Hopping Motor .................................................................................................. 66
3.3.20 Gear One-way .................................................................................................. 67
3.3.21 Feeder Unit Front ............................................................................................. 68
3.3.22 Manual Feed Hopper Assy ............................................................................... 69
3.3.23 Guide Paper Input Assy.................................................................................... 70
3.3.24 Two Lever Input Sensors, Lever 2nd Feed Sensor .......................................... 71
3.3.25 Roller Registration, Roller Assy Hopping ......................................................... 72
3.3.26 Roller Hopping.................................................................................................. 73
3.3.27 PXU PCB/PXM PCB, Lever Resist Sensor ...................................................... 74
3.3.28 Paper End Lever............................................................................................... 75
3.3.29 PCO PCB (Operator Panel).............................................................................. 76
3.3.30 Holder Gear Toner Assy................................................................................... 77
3.3.31 Plate Latch Lever (FD), Spring Latch Lever (FD) ............................................. 78
3.3.32 Belt Cassette Assy ........................................................................................... 79
3.3.33 High Voltage Power Supply Unit, Bracket HV (BT) Assy ................................. 80
3.3.34 Eraser Bracket Assy, Eraser Bracket (KCM) Assy ........................................... 81
3.3.35 Shaft Link.......................................................................................................... 82
3.3.36 Contact (BL-R) Assy, Contact (CL-R) Assy ...................................................... 83
3.3.37 Contact (BL-L) Assy, Contact (CL-L) Assy ....................................................... 84
3.3.38 Contact SB Assy............................................................................................... 85
3.3.39 PXC PCB .......................................................................................................... 86
3.3.40 Heat Unit Assy.................................................................................................. 87
3.3.41 Oil Roller Assy .................................................................................................. 88
3.3.42 Lever Lock Heat (L)/(R), Guide Side Heat, Spring Lock................................... 89
3.3.43 PXL PCB .......................................................................................................... 90
3.3.44 Heat Unit Guide Assy ....................................................................................... 91
3.3.45 Holder LED Assy, LED Head............................................................................ 92
4. ADJUSTMENTS .............................................................................................93
4.1 Maintenance Modes and Their Functions...................................................................... 93
4.1.1 User maintenance mode .................................................................................. 93
4.1.2 System maintenance mode .............................................................................. 95
4.1.3 Engine maintenance mode ............................................................................... 97
4.2 Adjustments after Parts Replacement ......................................................................... 100
4.2.1 Confirm the LED head driving time................................................................. 100
4.2.2 Color deviation correction............................................................................... 102
5. PERIODIC MAINTENANCE ......................................................................... 105
5.1 Periodically Replaced Parts ......................................................................................... 105
5.2 Cleaning....................................................................................................................... 105
5.3 Cleaning the LED Lens Array ...................................................................................... 105
5.4 Cleaning the Pickup Roller........................................................................................... 105
6. TROUBLESHOOTING PROCEDURES ....................................................... 106
6.1 Troubleshooting Tips ................................................................................................... 106
6.2 Points to Check before Correcting Image Problems.................................................... 106
6.3 Tips for Correcting Image Problems ............................................................................ 106
6.4 Preparation for Troubleshooting .................................................................................. 107
6.5 Troubleshooting Flow................................................................................................... 107
6.5.1 LCD status message/trouble list..................................................................... 107
6.5.2 LCD message troubleshooting ....................................................................... 116
6.5.3 Image troubleshooting .................................................................................... 129

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7. WIRING DIAGRAM...................................................................................... 146
7.1 Resistance Check ........................................................................................................ 146
7.2 Program/Font ROM Location ....................................................................................... 150
8. Parts List......................................................................................................154
Appendix A CENTRONICS PARALLEL INTERFACE....................................175
Appendix B HIGH CAPACITY SECOND PAPER FEEDER ........................... 179
1. OUTLINE ......................................................................................................179
1.1 Functions ..................................................................................................................... 179
1.2 External View and Component Names........................................................................ 179
2. MECHANISM DESCRIPTION ...................................................................... 180
2.1 General Mechanicsm................................................................................................... 180
2.2 Hopper Mechanism...................................................................................................... 181
3. PARTS REPLACEMENT..............................................................................182
3.1 Precautions Concerning Parts Replacement............................................................... 182
3.2 Parts Layout................................................................................................................. 184
3.3 Parts Replacement Methods........................................................................................ 185
3.3.1 Idle rollers ....................................................................................................... 186
3.3.2 AOLT-PCB...................................................................................................... 187
3.3.3 Hopping motor ................................................................................................ 188
3.3.4 Feed roller ...................................................................................................... 189
3.3.5 Hopping roller ................................................................................................. 190
3.3.6 Side frame (L) assy ........................................................................................ 191
3.3.7 Side frame (R) assy........................................................................................ 192
4. TROUBLESHOOTING.................................................................................. 193
4.1 Precautions Prior to the Troubleshooting..................................................................... 193
4.2 Preparations for the Troubleshooting........................................................................... 193
4.3 Troubleshooting Method .............................................................................................. 194
4.3.1 LCD Status Message List ............................................................................... 194
4.3.2 Troubleshooting Flow ..................................................................................... 195
5. CONNECTION DIAGRAM............................................................................ 196
5.1 Interconnection Diagram.............................................................................................. 196
5.2 PCB Layout.................................................................................................................. 197
6. PARTS LIST ................................................................................................. 198

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MM M M M M M M
LED head Discharging indicators
Centronics interface
HSP Controller Junction board Pulse motors
Engine controller
Low-voltage
power unit
Fixing unit
High-voltage
power unit Second tray
Belt unit
<Sensors, switches, and thermistors>
Paper width sensor Form size detector (4 bits) Form end sensor FF form end FF home switch Form feed sensor 1 Form feed sensor 2 Write sensor Ejection sensor Toner Low (Y.M.C.K) EP Up/Down (Y.M.C.K) Waste toner sensor Resist Up/Down Cover open switch (High-voltage interlock switch) Heater temperature thermistor Backup temperature thermistor Environment temperature sensor Environment humidity sensor Oil Roller switch Fixing unit interlock switch Waste toner box switch
Y-EP unit M-EP unit C-EP unit B-EP unit
PSIMM
x2
interface
SIMM
x4
interface
Y EP M EP C EP K EP BELT HEATER REGIST FF
Operator panel
1. SPECIFICATIONS
1.1 Basic System Configuration
The basic system configuration of OKICOLOR 8 / OKIPAGE 8c Plus is illustrated in Figure 1.1.
Figure 1.1

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1.2 Printer Specifications
This printer unit is composed with the following hardware.
• Electro-photographric processor
• Paper feeder
• Controller (CU part / PU Part)
• Operator panel
• Power board (High voltage part / PU part)
Figure 1-2 show the printer unit configuration.
Figure 1.2
Face-up Stacker Assy
Stacker Cover Assy
Rear Cover
Side Cover (L) Assy
Base Unit Operator Panel Assy
I/F Cover Assy

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1.3 Option Specifications
Options available for OKICOLOR 8 / OKIPAGE 8c Plus are as follows.
(1) 2nd-Feeder
(2) RAM SIMM module (72 pin SIMM, 4MB/8MB/16MB/32MB)
* Make sure to use a set of 2 of the same volume size modules.

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1.4 Basic Specifications
(1) Dimensions
Width: 18.8" (478mm) Length: 24.5" (622mm) Height: 15.6" (396mm)
(2) Weight
Approx. 48kg (106lbs)
(3) Form
Type: Ordinary paper (Hammermill 24lbs) and OHP (Only CG3710)
Recommended paper (for color printing)
Color laser paper (20lb to 24lbs)
Note: The printout color tones are dependent upon the whiteness of the print
paper
Sizes: Letter, Legal (13"or 14"), Executive, A4, A5, B5, and A6 (1st tray and front feeder)
Reams: 1st tray 20lbs to 28lbs
2nd tray 20lbs to 28lbs
Front feeder 20lbs to 44lbs
(5) Printing speed
8 pages per minute (5 pages per minute: OHP/ 34lbs ~44lbs, 123g/m2~166g/m2)
(6) Resolution
600 dots per inch x 600 dots per inch
(7) Input voltage
120VAC +5.5%, -15%
230VAC ±10%
(8) Power consumption
Peak W
Typical operation W
Idle W
Power-save mode W
(9) Frequency
50Hz or 60Hz +2%, -2%
(10) Noises
Operating: 54dB (without 2nd tray), 55dB (with 2nd tray)
Standby: 45dB
Power-saving: 43dB
(11) Expendibles and service life
Toner cartridge: Approx. 1800 pages (5% duty) (each of Y, M, C, and K)
(Approx. 1000 sheets for the first)
Image drum: Up to 12,000 pages (5% duty, continuous) (each of Y, M, C, and K)
Waste Toner Box: Up to 25,000 Sheets
(under typical printout conditions: Single images of 5% density,
equivalent to printout using 14 toner cartridges)
Oil Roller Unit: Up to 10,000 sheets (Life defined in the number of actually printed
paper sheets)
(12) Periodically-replaced parts
Heat Unit Assy: 60,000 pages
Belt Cassette Assy: 50,000 pages