Okidata OL840, OL830, OL820, OL800, OL400 Service Manual

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Service Guide OL400

Chapter 0 About This Manual

OL400 / 800 / 820 / 830 / 840

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copy of the OKIDATA Service Training Manual.

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Table of Contents Page

Service Guide OL400

0 About This Manual

Front Cover 1 Copyright & Manual Revision 2 Part Number 3

1 Product Specifications

1.1 Overview 4

1.2 Physical Specifications 5

1.3 Print Specifications 6

1.4 Paper Specifications 7

1.5 Power Requirements 8

1.8 Options 9

1.9 Consumables 10

1.10 Reliability Data 11

2 Principles of Operation

2.1 Printer Overview 12

2.2 Main Control Function 13

....2.2.02 Centronics Parallel Interface 14

....2.2.03 RS-232C Serial Interface 15

....2.2.04 Optional Font Card 16

....2.2.05 Optional RAM Board / IC Set 17

2.3 Printer Control Function 18

....2.3.02 Operation Panel 19

....2.3.03 Engine Board 20

....2.3.04 Power Supply Unit 21

....2.3.05 Fuser Unit 22

....2.3.06 Main Motor (Drum Motor) 23

....2.3.07 LED Head 24

....2.3.08 Resist Motor 25

....2.3.09 DC Fan 26

2.4 Mechanical Operation Description 27

....2.4.02 OL400 Printing Process 28

....2.4.03 Process Descriptions 29

2.5 Sensors And Switches 30

....2.5.01 Sensors and Switches 31

....2.5.02 Sensor Functions 32

3 Maintenance & Disassembly

3.1 Maintenance 33

....3.1.02 Maintenance Tools 34

....3.1.03 Maintenance Precautions 35

3.2 Disassembly/Assembly Procedures 36

....3.2.01 Upper Cover 37

....3.2.02 LED Head 38

Table of Contents Page

....3.2.03 Interface Board 39

....3.2.04 RAM Board (Option) 40

....3.2.05 Main Controller Board 41

....3.2.06 Engine Controller Circuit Board (LLAB) 42

....3.2.07 Main Motor 43

....3.2.08 DC Fan Assembly 44

....3.2.09 Idle Gears "A" and "B", and the Reduction Gear 45

....3.2.10 Power Supply Unit 46

....3.2.11 Upper Unit 47

....3.2.12 Fusing Unit 48

....3.2.13 Backup Roller 49

....3.2.14 Transfer Charger Assembly 50

....3.2.15 Resist Roller Assembly 51

....3.2.16 Idle Gear C 52

....3.2.17 Paper Supply Unit 53

....3.2.18 Resist Motor 54

....3.2.19 Engine Connection Board 55

....3.2.20 Hopping Roller 56

....3.2.21 Separator 57

....3.2.22 Ozone Filter 58

3.3 Adjustments And Service Checks 59

....3.3.02 Actual Page Count 60

....3.3.03 Modified Page Count 61

....3.3.04 Vertical Print Start Position Adjustment 62

....3.3.05 Setting the LED Head Drive Time 63

....3.3.06 Voltage Adjustment (+5 vdc) 64

....3.3.07 Darkness Control 65

3.4 Cleaning 66

4 Failure & Repair Analysis

4.1 Overview 67

4.2 Troubleshooting Updates 68

4.3 Reporting Problems 69

4.4 Troubleshooting Tips 70

4.5 Fault Alarms 71

....4.5.02 Error Messages Table 72

....4.5.03 Output SamplesTitle of Section 73

4.6 Repair Analysis Procedures 74

....4.6.02 RAP Index 75

........RAP 01 Printer Does Not Initialize 76

........RAP 02: Paper Feed Jam Alarm 77

........RAP 03: Paper Jam Alarm 78

........RAP 04: Size Tray Error Alarm 79

........RAP 05: Engine Error - Fusing Problem Alarm 80

........RAP 06: Engine Error Alarm 81

Table of Contents Page

........RAP 07: Light or Blurred Images 82

........RAP 09: Blank Output 83

........RAP 10: Vertical Black Stripes 84

........RAP 11: Repeating Marks 85

........RAP 12: Blank Spots 86

........RAP 13: Vertical White Stripes 87

........RAP 14: Black Page 88

........RAP 15: Poor Fusing 89

4.7 Self-Tests 90

A Reference Charts

A.1 Overview 91 A.2 Charts 92

....A.2.01 Main Controller Board (LBPE / LBPF) 93

....A.2.02 Engine Controller Board (LLAB) 94

....A.2.03 Operator Panel PCB (LLDC) 95

....A.2.04 Engine Connection PCB (LLCC) 96

....A.2.05 Centronics Parallel Interface PCB (LLCP / LLCQ) 97

....A.2.06 RS-232C Interface PCB (LLRS) 98

....A.2.07 Expansion RAM Board (optional) (RAMK / RAMH) 99

....A.2.08 Power Interconnect Board (LLIE) 100

....A.2.09 Power Supply Unit 101

B Illustrated Parts Listing

B.1 Illustrated Parts Listing 102

....B.1.02 Definitions of Terms 103

....B.1.03 Parts Ordering Information 104

B.2 Charts 105

....B.2.01 Items 1 - 7 106

....B.2.02 Items 8 - 16 107

....B.2.03 Items 17 - 27, and 41 108

....B.2.04 Items 28 - 35 109

....B.2.05 Items 36 - 40 110

Service Guide OL400

Chapter 0 About This Manual

This document may not be reproduced without written permission of the Okidata® Technical Training Group. Every effort has been made to ensure the accuracy of the information contained in this training course. Okidata is not responsible for errors beyond its control.

Second Edition May, 1994 Written and produced by the Okidata Technical Training Group Please address any comments on this publication to:

Technical Training Group Okidata 532 Fellowship Road Mount Laurel, NJ 08054-3499

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Fax Number: (609) 235-2600, ext. 7034 Okilink Login Name: Technical Training

Okidata is a registered trademark of Oki Electric Industry Company, Ltd.; marques deposee de Oki Electric Industry Company, Ltd.; marca registrada, Oki Electric Industry Company, Ltd.

Microline is a registered trademark of Oki Electric Industry Company, Ltd. Centronics is a registered trademark of Centronics Inc. Diablo is a registered trademark of Xerox Corporation Epson is a registered trademark of Seiko Epson Corporation IBM is a registered trademark of International Business Machines, Inc. LaserJet and LaserJet+ are registered trademarks of Hewlett Packard Corporation Proprinter is a registered trademark of International Business Machines, Inc.

Note: The OL400 Service Training course is part of the OL-Series Training Course and can not be purchased separately.

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Service Guide OL400

Chapter 0 About This Manual

Note: The OL400 Service Training course is part of the OL-Series Training Course and can not be purchased separately.

THE OL400/800/820/830/840 VIDEO TRAINING KIT covers the following products:

OL400 OL800 OL820 OL830 OL840

The following items are included in the kit:

OL400 Service Handbook OL800/820 Service Handbook OL830 Service Handbook OL840 Service Handbook Service Training Video OL400/800/820 User's Documentation OL830 User's Documentation OL840 User's Documentation

Price: $95.00 ($124.00 Canadian)

P/N 58226902

Service Guide OL400

Chapter 1 Product Specifications

1.1 OVERVIEW

1.1.01 General Information

The OL400 is a desktop, page printer, using a stationary LED head and dry electrophotography as its exposure and development method. The printer has a resolution of 300 x 300 dots per inch and a continuous print speed of 4 letter-sized sheets per minute.

A 512K page memory is standard on the OL400; this can be expanded to 1.5 or 2.5 megabyte with an optional RAM printed circuit board and a memory expansion chip set. Twenty-five resident fonts are included in the OL400 and five optional font cards are currently available. Downloadable fonts can also be used with this printer.

The printer can be purchased with either a Centronics parallel interface or an RS-232C serial interface.

The OL400's consumables consist of the toner kit, which include a toner cartridge, lens cleaner, and a fuser cleaner pad and the image drum kit which includes the drum cartridge and ozone filter.

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A letter-size paper tray is included with the printer, and legal, and envelope trays are also available. Paper feeding can be done automatically or manually.

The printer will print on a variety of paper types, labels, envelopes, and transparencies.

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Service Guide OL400

Chapter 1 Product Specifications

1.2 PHYSICAL SPECIFICATIONS

1.2.01 Outside Dimensions

Width: 17.72" Height:5.24" Length: 17.72"

1.2.02 Printer Weight 24 lbs.

1.2.03 LED Array Number of LED Elements - 2560

Service Guide OL400

Chapter 1 Product Specifications

1.3 PRINT SPECIFICATIONS

1.3.01 Print Specifications

Development method: Dry electrophotography Exposure method: LED stationary head

1.3.02 Print Speed

First print: 28 seconds maximum (letter size) Continuous print: 4 sheets/minute. (letter size) Warm-up time: 40 seconds maximum [at room temperature 77oF (25oC) and rated voltage (120

VAC)]

1.3.03 Symbol Sets

Thirty-nine symbol sets are available with the OL400.

1.3.04 Available Fonts

There are twenty-five resident fonts in the OL400.

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1.3.05 Paper Feed Method

Automatic feed Manual Feed

1.3.06 Paper Delivery Method

Face down/face up

1.3.07 Resolution

300 x 300 dots/inch

1.4 PAPER SPECIFICATIONS

1.4.01 Paper Types

Letter Size: 8.5" x 11"

Feed: Automatic or Manual Weight:Minimum 16 lbs Maximum 24 lbs Recommended 20 lbs

Legal Size: 8.5" x 14"

Feed: Automatic (with optional paper tray) or Manual Weight:Minimum 16 lbs Maximum 24 lbs Recommended 20 lbs

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Service Guide OL400

Chapter 1 Product Specifications

Envelope Size:Minimum 3.5" x 7.5"

Maximum 7.2" x 10.1" Feed: Automatic (with optional paper tray) or Manual Weight:Minimum 16 lbs Maximum 24 lbs Recommended 20 lbs

Labels Manual feed / Face up delivery only

Use labels designed specifically for laser/page printers. Transparencies Manual feed / Face up delivery only Must be able to withstand the heat of the fusing process.

1.5 POWER REQUIREMENTS

1.5.01 Input Power

120 VAC +5.5%, -15% 220/240 VAC +/-10%

1.5.02 Power Consumption

Approximately 800 W maximum during operation

1.6 ENVIRONMENTAL CONDITIONS

1.6.01 Ambient Temperature and Relative Humidity While operating: 50° to 89° F

10° to 32° C 20 to 80% Relative Humidity

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Service Guide OL400

Chapter 1 Product Specifications

While in storage: 14° to 122° F

10° to 50° C

1.6.02 Printer Noise Level During operation: At standby:

1.7 AGENCY APPROVALS

FCC Class B UL 478 Ver.5 CSA 22.2 220

50 dB maximum

43 dB maximum

Service Guide OL400

Chapter 1 Product Specifications

1.8 OPTIONS

1.8.01 RAM Expansion Board

1 megabyte (expands printer memory to 1.5 megabyte) Technician installed

1.8.02 RAM Expansion Chip Set

Technician installed 1 megabyte memory expansion chip set used in conjunction with the RAM Expansion Board option. (expands printer memory to 2.5 megabyte)

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1.8.03 Font ROM Cards

Tax Courier Roman Prestige Elite Letter Gothic

1.8.04 Paper Trays

Letter size Legal size Envelope

1.8.05 Interface Boards

RS-232C Serial Interface Board Centronics Parallel Interface Board Technician installed

1.9 CONSUMABLES

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Service Guide OL400

Chapter 1 Product Specifications

Toner Cartridge Kit One Toner Cartridge One Fuser Cleaner Pad One LED Head Cleaning Kit Image Drum Cartridge One Image Drum Cartridge One Ozone Filter

(P/N 52104201)

(P/N 56106601)

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Service Guide OL400

Chapter 1 Product Specifications

1.10 RELIABILITY DATA

1.10.01 Printer Mean Time Between Failure (MTBF)

Approximately 18,000 pages

1.10.02 Printer Mean Time To Repair (MTTR)

Approximately 20 minutes

1.10.03 Estimated Printer Life

Approximately 180,000 pages (5 years)

1.10.04 Printer Duty Cycle

Approximately 3,000 pages @ 5% print density

Service Guide OL400

Chapter 2 Principles of Operation

2.1 PRINTER OVERVIEW

2.1.01 General Information

This section describes the operation of the printer in the order listed below.

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Main Control Function { Printer Control Function { Mechanical Operation { Sensors and Switches {

} } } }

Service Guide OL400

Chapter 2 Principles of Operation

2.2 MAIN CONTROL FUNCTION

2.2.01 General Information

The main control function controls the reception of data from the host interface, processes command signals, processes the image signals, controls the printer unit, outputs data, and controls the operation panel.

The main control function consists of the items listed below.

CPU 80186-8 Font ROM (512 kbytes) Page buffer (512 kbytes) DRAM controller chip (MSM73V007) Print controller chip (MSM75HJ014) Font controller chip (MSM60791) Programmable I/O (82C55A-2GS) Interface Control Centronics Parallel Interface Board RS-232C Serial Interface Board Optional Font Card Optional RAM

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Service Guide OL400

Chapter 2 Principles of Operation

2.2.02 Centronics Parallel Interface

The following operations are carried out during SELECT mode once the STB-N signal is received from the host interface.

The BUSY-P signal is sent to the host interface. Simultaneously with fetching data to the Q4 IC at the last transition of the STB signal, the

RXIPT-P signal is sent to the CPU to inform it of receipt of data. The CPU reads data received from the Q4 IC by the RD-N signal, and turns off the BUSY signal

to the host interface. Upon turning off the BUSY signal, the ACK-N signal is sent to the host interface to acknowledge

reception processing.

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Service Guide OL400

Chapter 2 Principles of Operation

2.2.03 RS-232C Serial Interface

The 8251 Universal Synchronous/Asynchronous Receiver Transmitter is used as a controller. This serial I/F converts serial data received from the host I/F into parallel data for use by the CPU. It also converts parallel data from the CPU into serial data to be sent to the Host I/F.

READY/BUSY or X-ON/X-OFF are used as the communication protocol between the Host I/F and OL400. These can be selected through the Menu.

The baud rate, character length, parity check, stop bit, etc., are automatically written into the 82C51 from the menu, so hardware switches are not required.

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Service Guide OL400

Chapter 2 Principles of Operation

2.2.04 Optional Font Card

In addition to the twenty-five resident fonts, an optional font IC card is available. The CD-N signal detects the option font card.

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Service Guide OL400

Chapter 2 Principles of Operation

2.2.05 Optional RAM Board / IC Set

The expansion RAM board contains 1 Mbyte of memory and sockets for an additional 1 Mbyte. This RAM is in addition to the 512 Kbyte on the Main Control Board.

Service Guide OL400

Chapter 2 Principles of Operation

2.3 PRINTER CONTROL FUNCTION

2.3.01 General Information

The principle hardware components of the printer unit consist of the items listed below.

Operation Panel Engine Board Power Supply Unit Fuser Unit Main Motor LED Head Resist Motor DC Fan

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Service Guide OL400

Chapter 2 Principles of Operation

2.3.02 Operation Panel

The following components make up the operation panel.

4-bit MPU (LC6543C) LCD control driver (MSM6222B or HD44780) LCD display (16 characters per line) Operation panel sheet LEDs (for online mode indication) Operation buttons

The LCD control driver (MSM622B or HD44780) converts 4-bit character codes received from the MPU into 8-bit character codes and retrieves the character pattern data (font) associated with the 8-bit character codes from the internal character generator for display on the LCD.

Operation Panel Interface

The operation panel is controlled by the operation panel interface located on the Main Control Board via the Engine Board.

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Service Guide OL400

Chapter 2 Principles of Operation

2.3.03 Engine Board

The Engine Board is composed of the items listed below.

MPU80C51, or MPU83C154 (8-bit CPU) LLAB Revision 11

The MPU 83C154 contains the printer control program in its internal ROM.

Therefore, the external ROM (Q1) is not required on Revision 11. MSM73H019GS (80 pin LSI) EPROM (Printer Control Program) EPROM

This 1-Kbit electrically erasable PROM (EEPROM) is loaded with the following data:

Total number of sheets printed after installation Total number of sheets printed with the current drum Total number of sheets printed with the current fuser Setting of time required from the completion of printing to Stand-by Feed length needed to feed the paper to a printable position. Print starting line on paper (Top margin) LED head drive time.

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NOTE

The EEPROM preserves the above data while the supply voltage is off. The count of the total number of sheets printed after installation cannot be reset. The count of the total number of sheets printed with the drum currently in use should be

taken as a rough measure of the useful life of the drum.

It is reset to zero when the drum is replaced by holding down the RESET button and

applying power to the printer.

Service Guide OL400

Chapter 2 Principles of Operation

2.3.04 Power Supply Unit

The power supply unit generates the following voltages from the AC input voltage.

Voltage Purpose

+5vdc Logic Levels, LED Head Drive Voltage +12vdc Interface Line Voltage

-12vdc Interface Line Voltage +38vdc Motor/Fan Drive Voltage: High Voltage Source +5Kvdc Transfer Charge Voltage

-6Kvdc Drum Charge Voltage

-600vdc Charge Grid Voltage

-550, -400vdc Developer Bias Voltages

High Voltage Drive

The high voltage circuit provides a charge voltage (about -6Kvdc), a transfer voltage (about +5 Kvdc), a grid voltage (about -600 vdc), and a developer bias voltages (about -550vdc and

-400vdc). Of these voltages, the first two are generated from a high voltage power supply. The grid connects to the ground via a varistor on the medium-voltage generation circuit (LLAB-PCB). It is kept at about -680 vdc during charging.

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Service Guide OL400

Chapter 2 Principles of Operation

2.3.05 Fuser Unit

The fuser unit heater is controlled by a thermistor, a comparator, an LSI, and a CPU to keep the heat roller surface temperature within a predetermined range (about 150 degrees). A thermostat within the fuser unit prevents abnormal temperature rises in the fuser unit if the thermistor fails.

NOTE:

The CPU checks for a blown or shorted wire in the thermistor at power-on , setting a fuser alarm if an error is detected.

The CPU also sets a fuser alarm if the proper temperature is not attained within a specified period of time after power-on.

Upon detecting a fuser alarm, the CPU will halt (after printing the current page).

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Service Guide OL400

Chapter 2 Principles of Operation

2.3.06 Main Motor (Drum Motor)

The main motor is driven by the motor drive IC (M54646). It is a two-phase motor, driven by the DM-PH1 and DM-PH2 signals.

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Service Guide OL400

Chapter 2 Principles of Operation

2.3.07 LED Head

Data on the 2,560 LEDs in the LED head is set in the shift register by the HD CLK signal. The data is loaded in the latch circuit by the HD LD signal.

The on/off states of the LEDs are controlled by the signals STB1- STB4; 640 bits are turned on or off at a time.

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Service Guide OL400

Chapter 2 Principles of Operation

2.3.08 Resist Motor

The resist motor is driven clockwise (Hopping), then counterclockwise (Paper Feed) by the motor drive IC (LB1731). It is four-phase motor, driven according to the RM-H1, RM-H2, and RM ON-P signals.

Service Guide OL400

Chapter 2 Principles of Operation

2.3.09 DC Fan

The fan is controlled by the FAN ON-P signal from the LSI (MSM73H019). In order for the fan to operate, the signal FAN SENSE-N must be active.

NOTE:

The fuser and the fan are not driven when the cover is open (reset). If the fan fails to run, the fuser will turn off and an alarm is set. This prevents the next printout. If

the signal Fan Sense-N becomes inactive while printing, both the heater and the fan come to a halt after the end of printout of the current page.

A fan alarm is generated when the fan is not sensed at power-on time. The fan is driven for 1 minute after the fuser has been turned off. The fan speed is reduced if the

next PRINT signal is not received within 1 minute.

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Service Guide OL400

Chapter 2 Principles of Operation

2.4 MECHANICAL OPERATION DESCRIPTION

2.4.01 Basic Principles of Electrophotography

The printer turns on the LED head according to the data received from the controller. A charged photoconductive material is exposed to light, forming a latent image on the material. This latent image is developed by toner, with the resultant toner image being transferred to paper and fused for printing.

The electrophotographic technology used in this printer is similar to that embodied in general copying machines. The technology comprises the following processes:

Charging

The surface of the photoconductive material is uniformly charged.

Exposure

The charged photoconductive material is exposed to light, forming a latent image associated with the print image on the photoconductive material.

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Developing

Charged toner is attracted to the latent image by static electricity, making the image visible.

Transfer

The toner is attracted to the paper by a static charge.

Cleaning

Toner that remains on the photoconductive material is returned to the developer.

Fusing

The toner is fused to the paper using heat and pressure.

Service Guide OL400

Chapter 2 Principles of Operation

2.4.02 OL400 Printing Process

The layout of the electrostatic printing process hardware is shown below.

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Service Guide OL400

Chapter 2 Principles of Operation

2.4.03 Process Descriptions

Hopping and Feeding

Hopping and feeding are accomplished by the resist motor, hopping roller, and resist rollers. Turning the resist motor in the clockwise direction drives the hopping roller. Turning the resist motor in the counter-clockwise direction drives the feed rollers.

Hopping

Hopping is loading paper from the tray. The resist motor turns the hopping roller to advance the paper until the inlet sensor turns on. After the paper has turned on the inlet sensor, the hopping roller advances the paper until it contacts the feed roller (a predetermined length).

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Feeding Feeding is transporting the paper through the printer After the end of hopping, the resist motor reverses and the resist rollers transport the paper

through the printer.

Charging

-6 Kvdc is applied to the charge wire. This causes negative ions to be generated in the vicinity of the charge wire (corona discharge). The negative ions are discharged to the grid plate and the image drum surface. Since the drum surface is not conductive (in the dark), the negative charge (approximately -700 vdc) remains on the drum. To ensure that the drum surface is not charged with more than -700 vdc, a varistor is connected between the grid and ground. If the grid voltage

exceeds -700 vdc, the varistor shunts this excess voltage to ground.

Exposure Light emitted from the LED head is radiated to the image drum surface which is charged with

negative ions. The areas of the drum that light is directed to become conductive. This allows the surface potential in these areas to drop from -700 vdc to approximately -100 vdc, thereby forming a latent image associated with the image signals.

Developing The toner supply roller and the development roller are supplied with bias voltages required during

the developing process. -550 vdc is supplied to the toner supply roller, -400 vdc to the development roller. The toner supply roller is constructed of a porous material which absorbs toner. Since the development roller charge is more positive than the toner supply roller charge, toner is attracted from the toner supply roller to the development roller.

The toner attracted to the development roller is scraped off by the doctor blade, forming a thin coat of toner on the development roller surface.

Since the areas of the drum exposed to light (-100vdc) are charged more positive than the toner (-400 vdc), the toner is attracted to the exposed areas of the Image drum surface, making the latent image visible.

Transfer As paper passes by the image drum surface, a positive charge (+5Kvdc), is applied to the charge

wire causing the paper to be charged positively through corona discharge. Since the paper is charged more positive than the toner (-100 vdc), the toner is attracted to the paper. #####

Cleaning Upon completion of transfer, residual toner on the image drum is scraped off by the cleaning

blade. The residual toner is returned from the toner recovery unit to the developer unit for reuse.

Fusing The toner image is fused on the paper by passing it between the heated roller and the back-up

roller. The heated roller is teflon coated and contains a 600 watt quartz lamp. The back-up roller and springs provides a pressure of 3 kg.

A thermistor regulates the heated roller temperature at a predetermined temperature (about 150° C). A thermostat cuts off voltage supply to the heater in the event of abnormal temperature rise.

Paper Ejection Paper is ejected from the fuser unit by the back-up roller. If the face-up stacker is closed, paper is

routed to the top of the printer for face-down delivery.

2.5 SENSORS AND SWITCHES

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Service Guide OL400

Chapter 2 Principles of Operation

Sensors & Switches ( Sensor Functions (

) )

2.5.01 Sensors and Switches

Inlet Sensor (Photosensor)

Outlet Sensor (Photosensor)

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Service Guide OL400

Chapter 2 Principles of Operation

Paper Tray Identification Switches

Paper End Sensor (Photosensor)

Cover Open Switch

Service Guide OL400

Chapter 2 Principles of Operation

2.5.02 Sensor Functions

At Power-On

The inlet and outlet sensors are checked for their on and off states at power on. Inlet sensor ON: Inlet jam error (Paper supply jam) Outlet sensor ON: Outlet jam error (Paper eject jam) The thermistor sensor circuit detects if the temperature of the fusing unit reaches the normal

temperature within the specified time. When it does not reach the normal temperature within the specified time, the thermistor sensor turns OFF the heater and generates an alarm.

During Hopping

Whenever the inlet sensor fails to detect paper within a predetermined period of time after a feed command has been issued to the paper supply system (tray), the failure is counted. A hopping operation is then attempted up to three times, and if the paper still fails to feed properly, an inlet jam error is established.

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During Feeding

If the leading part of the paper does not reach the outlet sensor within a predetermined period of time after the start of feeding by the resist motor, a feed jam error is established.

Detection of Form Length Errors by the Inlet Sensor

Any form length other than 11 or 14 inches will generate a form length error, causing an alarm to be set. To detect the form length, the processor counts the time from when the inlet sensor turns on until it turns off (after the start of the resist motor in the forward direction). Form length detection is not enabled for manually inserted paper or envelopes.

Detection of Outlet Jams by the Outlet Sensor

Since paper is fed through the printer at a fixed speed, the outlet sensor must remain on for a predetermined length of time. If the sensor remains on in excess of this time, the controller assumes that an exit jam has occurred and an alarm is generated.

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.1 MAINTENANCE

3.1.01 General Information This section lists the parts replacement, adjustment, cleaning, and lubrication procedures. Disassembly should not be performed unless absolutely necessary. NEVER perform disassembly

on a malfunctioning unit until you have followed the failure analysis procedures in Section Four of this Service Handbook.

Follow the procedures listed in Adjustments and Service Settings. Adjustments may be required when either consumables or parts are replaced. Failure to perform these procedures could result in unnecessary service calls.

Cleaning procedures must be performed correctly if high print quality is to be achieved.

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Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.1.02 Maintenance Tools

The following tools are required to service the unit.

#2 Phillips Screwdriver (with magnetic tip) Straight-slot Screwdriver Needle Nose Pliers (4 Inch) Digital Multimeter Shop Vacuum (with filter for toner) Cloth (soft and lint-free) All-purpose Cleaner Grease (Dow Corning BR2 or equivalent)

3.1.03 Maintenance Precautions

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Service Guide OL400

Chapter 3 Maintenance & Disassembly

DO NOT

Before starting disassembly and assembly, always power OFF the unit and detach the power cord.

Detach the interface cable, if installed. Do not remove parts unnecessarily. Try to keep disassembly to a minimum. Use the recommended maintenance tools. When disassembling, follow the listed sequence. Failure to follow the correct sequence

may result in damaged parts. Screws, collars and other small parts are easily lost. Temporarily attach these parts to

their original positions. When handling circuit boards use extreme care. Integrated circuits (microprocessors,

ROM, and RAM) can be destroyed by static electricity. Do not place printed circuit boards directly on conductive surfaces. Follow the recommended procedures when replacing assemblies and units. Clear the drum counter when a new drum cartridge is installed.

disassemble the unit if it is operating normally.

1. Power OFF the unit.

2. Press and hold RESET while powering ON the unit.

3. The drum counter will reset.

Clear the fuser counter when a new fusing unit is installed. Refer to Section 3.3, Adjustments in this Service Handbook.{

}

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Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2 DISASSEMBLY/ASSEMBLY PROCEDURES

General Information

This section contains the printer disassembly procedures. Only the removal procedures are explained. Reverse the procedure for the installation.

This Service Handbook lists the disassembly procedures for major components of the unit. Okidata does perform disassembly during this training, Okidata recommends that you perform only the disassembly procedures for RSPL items. All other procedures are provided to assist you in identifying parts. It is not likely that you will perform these procedures while servicing the product.

Read all notes, cautions, and warnings. They contain important information regarding assembly/disassembly.

NOT

recommend disassembling a unit which is operating normally. If you decide to

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.01 Upper Cover

1. Turn the power switch OFF and unplug the AC power cord from the outlet and the printer power receptacle at the rear of the printer.

2. Remove the paper tray (1), interface cable (2), and font card (3) (if installed).

3. Lift the operator panel assembly (4) at its bottom and detach it.

4. Pull on the locking collar and then detach the connecting cable (5) from connector J1 (6) of the operator panel PCB (7).

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NOTE:

5. Please note that when assembling the operator panel board, you must install the connecting cable with the blue strip to the left.

6. Press the "OPEN" button (8) and raise the stacker cover (9).

7. Remove the two screws (10) and lift the front side of the upper cover (11). As you lift, you will disengage the upper cover from the lower cover at the back of the printer.

NOTE:

Installation

Open the stacker cover. Align the square slots of the upper cover with the claws of the lower cover. The claws are located

on the back of the lower cover, at the left and right sides. Lower the upper cover into position. If the cover is not installed properly, paper jams will result.

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.02 LED Head

1. Perform this procedure:

3.2.01{

2. Push the two blue lock levers (1) toward the rear of the printer and open the LED holder (2).

3. Lift and remove the image drum cartridge (3). To protect the image drum cartridge, please place it back in the styrofoam shipping package.

4. Squeeze the LED head (4) and the LED holder together to ease the tension on the springs (5). Use a screwdriver to remove the two clamps (6) from the claws of the LED head. The claws are located on the top and bottom of the left and right sides of the holder.

5. Gradually remove the LED head, being careful to keep the springs in place.

}

Page: 38

NOTE: LED Head Replacement After replacing the LED head, set the LED head drive time as described in Section 3.3 of this

Service Handbook.{ }

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.03 Interface Board

This procedure may be used to remove both the parallel and serial interface boards.

1. Perform this procedure:

3.2.01{

2. Remove the three shield cover mounting screws (1) and detach the shield cover (2) by sliding it forward and lifting it.

3. Remove the interface board mounting screw (3) and the post (4).

4. Lift the interface board (5) to disconnect it from the control board (6) for removal.

}

Page: 39

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.04 RAM Board (Option)

1. Perform this procedures:

3.2.01{

2. Remove the three shield cover mounting screws (1) and detach the shield cover (2) by sliding it forward and lifting it.

3. Press the hook of the locking circuit board support (3) to unlock the RAM board (4).

4. Lift the RAM board to disconnect it from the main controller board (5) for removal.

}

Page: 40

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.05 Main Controller Board

1. Perform these procedures:

3.2.01{

3.2.03{

3.2.04{

2. Remove the three controller board mounting screws (1).

3. Lift the main controller board (2) to disconnect it from the engine control circuit board (3) and remove the main controller board.

} } }

Page: 41

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.06 Engine Controller Circuit Board (LLAB)

1. Perform these procedures:

3.2.01{

3.2.03{

3.2.04{

3.2.05{

2. Disconnect the cables (1) from connectors J1, J2, and J5.

3. Open the LED holder to allow access to the engine board mounting screw (2) and remove the mounting screw.

4. Close the LED holder and raise the upper unit.

5. Remove the two remaining mounting screws (3).

} } }

}

Page: 42

CAUTION:

Be careful not to lose the plastic spacer (4) located between the shield frame and the engine controller board. When installing the engine controller board, be sure that the spacer is in place or the engine controller board will short against the shield frame.

6. Lift the engine controller board (5) to disconnect it from the interconnect board (6).

7. On the engine controller board, press the pawls (7) to unlock and remove the print board cover (8).

NOTE:

Replacement

When replacing an engine controller board, remove the EEPROM IC2 (9) and the Program PROM Q1 (10) from the old board and mount them on the new board. With LLAB Revision 11, Q1 is not installed because the program is masked in the CPU.

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.07 Main Motor

1. Perform these procedures:

3.2.01{

3.2.03{

3.2.04{

3.2.05{

3.2.06{

2. Remove the three mounting screws (1) and detach the shield frame (2).

3. Detach the interconnect board (3).

NOTE:

The traces which run the entire length of the board are to the front of the printer when the board is installed.

} } }

}

Page: 43

4. Working from the bottom of the printer, remove the motor cover (4) by releasing the two black claws (5).

5. Remove the two high voltage wires from the motor cover.

6. Shift the motor assembly to the left to remove it from the claws (6) of the lower unit.

7. Working on the motor assembly, remove the two mounting screws (7) to remove the main motor (8) from the motor assembly.

3.2.08 DC Fan Assembly

1. Perform these procedures:

3.2.01{

3.2.03{

3.2.04{

3.2.05{

3.2.06{

2. Detach the shield frame (3.2.07 step 6).

3. Remove the DC fan assembly (1).

} } }

}

Page: 44

Service Guide OL400

Chapter 3 Maintenance & Disassembly

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.09 Idle Gears "A" and "B", and the Reduction Gear

1. Perform these procedures:

3.2.01{

3.2.03{

3.2.04{

3.2.05{

3.2.06{

3.2.07{

2. Detach the gears in the following order: idle gear "B" (1), reduction gear (2) and idle gear "A" (3).

} } }

Page: 45

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.10 Power Supply Unit

1. Perform these procedures:

3.2.01{

3.2.03{

3.2.04{

3.2.05{

3.2.06{

3.2.07{

2. Disconnect the two high-voltage cables (1).

NOTE:

When installing, the cables are keyed for correct placement. The larger connector is to the front of the printer.

3. Remove the four mounting screws (2).

} } }

Page: 46

4. Raise the upper unit.

5. Slide the power supply unit (3) towards the front until it comes off the guide (4) of the lower unit.

6. Lift the power supply unit towards you to detach it from the rear claws (5) for removal.

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.11 Upper Unit

1. Perform these procedures:

3.2.01{

3.2.02{

3.2.03{

3.2.04{

3.2.05{

3.2.06{

3.2.07{

3.2.08{

3.2.10{

2. Place the face-up stacker assembly, located at the rear of the printer, down. Then, lift the upper unit.

3. Remove the paper eject roller assembly mounting screw (1). Slightly lift the paper eject roller assembly (2) at its left end and slide the left end backward using the right end as a pivot. Remove the assembly.

} } } }

} } } } }

Page: 47

4. Remove the tension springs (3) using a needle nose pliers.

5. Loosen the two mounting screws (4). Lift the upper unit (5).

6. Slide the upper unit to the right and work it free of the right slot to remove it.

CAUTION:

Be careful not to drop the fulcrum block (6) and the idle gear (7) when removing the upper unit.

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.12 Fusing Unit

WARNING: Allow the printer to cool before servicing the fusing unit.

1. Perform these procedures:

3.2.01{

3.2.02{

3.2.03{

3.2.04{

3.2.05{

3.2.06{

3.2.07{

3.2.08{

3.2.10{

3.2.11{

} } } }

} } } } } }

Page: 48

2. Working on the upper unit, remove fuser cleaner pad (1) and the fulcrum block with idle gear (2).

3. Detach the cable (3) from the cable guide (4) of the upper unit.

4. Pass the connector (5) through the slot in the upper unit and work the cable from the upper unit guides.

5. Position the upper unit so its underside is facing you, with the fusing unit (6) at the top.

6. Push the fusing unit against the upper unit until the two lock plates (7) protrude from their slots.

7. Slide the fusing unit to the right until the lock plates disengage from the grooves of the upper unit.

8. Remove the fusing unit, being careful not to lose the springs (8).

CAUTION:

Installation

The four separator claws must move freely within their grooves or paper jams will result.

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.13 Backup Roller

1. Perform these procedures:

3.2.01{

3.2.02{

3.2.03{

3.2.04{

3.2.05{

3.2.06{

3.2.07{

3.2.08{

3.2.10{

3.2.11{

2. Remove the two mounting screws (1).

3. Use a straight slot screwdriver to detach the sheet guide (2).

} } } }

} } } } } }

Page: 49

4. Remove the backup roller (3).

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.14 Transfer Charger Assembly

1. Turn the power switch OFF and unplug the AC power cord from the outlet.

2. Press the OPEN button and raise the stacker cover.

3. Remove the image drum cartridge (1). (See 3.2.2)

4. Push the lock lever (2) towards the back of the printer to raise the upper unit (3).

5. Firmly push down and back on the sides of the transfer charger assembly (4) until the lower cover claws are disengaged from the square holes on each end of the transfer charger assembly.

6. Lift and remove the transfer charger assembly.

Page: 50

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.15 Resist Roller Assembly

1. Perform these procedures:

3.2.01{

3.2.02{

2. Using a standard screwdriver, release the claws (1) from both sides of the resist roller assembly (2).

NOTE: The left claw can be accessed from the bottom of the printer.

3. Lift the resist roller assembly from the printer.

} }

Page: 51

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.16 Idle Gear C

1. Perform this procedure:

3.2.01{

2. Push the lock lever towards the back of the printer to raise the upper unit.

3. Using a needle nose pliers and working from the left side of the printer, push the post (1) to the right.

4. Remove the post.

5. Remove idle gear C (2).

}

Page: 52

NOTE:

The cutout (3) on the post should be positioned to the left side of the printer and on the top when installing.

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.17 Paper Supply Unit

1. Perform these procedures:

3.2.01{

3.2.02{

3.2.03{

3.2.04{

3.2.05{

2. Press the lock lever (1) backward and lift the upper unit (2).

3. Disconnect the cable (3) from connector J5 on the engine controller circuit board (4).

4. Remove the two mounting screws (5).

5. Lift the paper supply assembly (6) at its front until the frame of the unit comes off the guide pins, then move the unit towards you for removal.

} } } } }

Page: 53

3.2.18 Resist Motor

1. Perform these procedures:

3.2.01{

3.2.02{

3.2.03{

3.2.04{

3.2.05{

3.2.17{

2. Remove the two mounting screws (1).

3. Detach the resist motor (2).

} } } } } }

Page: 54

Service Guide OL400

Chapter 3 Maintenance & Disassembly

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.19 Engine Connection Board

1. Perform these procedures:

3.2.01{

3.2.02{

3.2.03{

3.2.04{

3.2.05{

3.2.17{

2. Remove the two mounting screws. (1)

3. On the paper supply unit, press the pointed end of the nylon latch (2), push out the head (3), and remove the latch.

} } } } } }

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4. Detach the engine connection board (4).

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.20 Hopping Roller

1. Perform these procedures:

3.2.01{

3.2.02{

3.2.03{

3.2.04{

3.2.05{

3.2.15{

3.2.17{

2. Remove the two screws (1) and slide the upper plate assembly (2) until the claws (3) are unlocked.

3. Push the hopping roller shaft (4) to the left to unlock it.

4. Remove the hopping gear pin (5).

} } } } } } }

Page: 56

5. Remove the E-clips (6).

6. Remove the hopping roller pin (7).

7. Slide the hopping roller shaft to the right and remove the hopping roller (8).

NOTE: When installing, always mount the hopping roller shaft above the ground plate, which is on the left side of the printer.

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.21 Separator

1. Perform these procedures:

3.2.01{

3.2.02{

3.2.03{

3.2.04{

3.2.05{

3.2.15{

3.2.17{

3.2.20{

2. Hold the separator (1) down and remove the escape lever (2) from the pins on the paper supply unit. Be careful not to lose the separator spring (3).

} } } } } } } }

Page: 57

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.2.22 Ozone Filter

NOTE:

An ozone filter is provided with the image drum cartridge kit. The filter should be replaced when the image drum cartridge is replaced.

Using a screwdriver, insert the blade under the lower portion of the fan cover (1) and twist the screwdriver to remove the fan cover.

Remove the ozone filter (2) from the fan cover.

Page: 58

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.3 ADJUSTMENTS AND SERVICE CHECKS

3.3.01 General Information

The first four adjustments (Actual Page Count, Modified Page Count, Vertical Print Start Position and LED Head Drive Time) are performed by changing addresses on the EEPROM located on the Engine Controller printed circuit board.

Before performing these adjustments, setup the printer as listed below.

1. Remove the upper cover.

2. Raise the upper unit.

3. Remove the image drum cartridge.

4. Override the cover open interlock switch.

Page: 59

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.3.02 Actual Page Count

General Information

The actual page counter counts the number of sheets printed by the printer.

Procedure

To display the value of the actual page counter, follow this procedure.

1. Power ON the printer while pressing Switch 1 on the Engine Controller Board. The LED (located on the Engine Controller Board) will flash once - then pause (the LED will continuously flash once - then pause) indicating that the printer is in Parameter 1 of the maintenance mode.

2. Press Switch 1 for five seconds. The LED will display the contents of the Parameter1 (Actual Page Counter) register as follows:

a. The long flash indicates start of count.

Page: 60

b. Short flashes indicate counter contents (most significant digit first). There will be a

pause between digits. c. Upon completion of the count,a long flash will indicate start of count. d. This process will loop until you press Switch 1 for five seconds. This will cause

the modified page count to be displayed. (refer to 3.3.02)

Example

Actual Page Counter = 235 pages

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.3.03 Modified Page Count

General Information

The modified page counter combines the main motor revolution time and the number of printed sheets. Drum replacement is determined by the modified page count.

Procedure

To check the modified page count, follow this procedure.

NOTE:

To access the Modified Page Count, you must first view the Actual Page Count.

1. After viewing the Actual Page Count, press Switch 1 for five seconds. The LED

will display the contents of the Parameter 1 (Modified Page Count) register.

2. To end this procedure, press Switch 1 for 1 second. The LED will perform one

short flash to indicate Parameter 1 is selected.

Page: 61

Example

Modified Page Counter = 142 The next step in this table is also the last step in the Actual Page Counter Table

Switch 1 Action

Press for 5 seconds Long Flash Start of Modified Page Count None On-Off-Pause 1st Digit = 1 None On-Off-On-Off-On-Off-On-Pause 2nd Digit = 4 None On-Off-On-Off-Pause 3rd Digit = 2 None Long Flash Start of Count Press for 1 second Flashes ON/OFF Parameter #1 - Selected

NOTE:

The number "0" is represented by 10 flashes The Actual and Modified Page Counters CANNOT be changed.

LED Display Description

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.3.04 Vertical Print Start Position Adjustment

General Information

The Vertical Print Start Position Adjustment is used to set the top of form position. Use this adjustment to correct print start variations between different OL400 printers, or to achieve a 4.6 mm vertical start position, the default value.

A chart of the EEPROM addresses and print start positions is shown below. The Vertical Print Start Position is Parameter 9.

Procedure

1. To change the Vertical Print Start Position, follow this procedure.

2. Power ON the printer while pressing Switch 1 on the Engine Control board. The LED will flash continuously, indicating that the printer is in Parameter 1 of the maintenance mode.

Page: 62

3. Press Switch 1 eight times to access Parameter 9. The LED will flash 9 times, indicating Parameter 9 has been selected.

4. Press Switch 1 once for 5 seconds. The contents of the Parameter 9 register will be displayed.

5. To modify the contents of the Parameter 9 register, press Switch 1 (momentarily) to step through the addresses (in accordance with the chart shown below).

6. To end the adjustment, press Switch 1 once for 5 seconds. The LED will flash 9 times, indicating Parameter 9.

NOTE:

Ten flashes represent the number zero. On the table below, Address 0 comes after Address 15

EEPROM Address / Print Start Position Table

EEPROM Address

0 DEFAULT 0 8 -4.0

1 +.5 9 -3.5

Print Start Position (in mm)

EEPROM Address

Print Start Position (in mm)

2 +1.0 10 -3.0

3 +1.5 11 -2.5

4 +2.0 12 -2.0

5 +2.5 13 -1.5

6 +3.0 14 -1.0

7 +3.5 15 -0.5

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.3.05 Setting the LED Head Drive Time

General Information

This adjustment is necessary only when replacing the LED head. However, if the luminous energy ratings of the new and original LED heads are the same, adjustment is not necessary. The luminous energy rating is on the label on the LED head. Digits three and two (reading from the right) are the drive time rating.

The LED Head Drive Time is Parameter 13.

Procedure

To change the LED Head Drive Time, follow this procedure.

1. Power ON the printer while pressing Switch 1 on the Engine Control board. The LED will flash continuously, indicating that the printer is in Parameter 1 of the maintenance mode.

2. Press Switch 1, twelve times to access Parameter 13. The LED will flash thirteen times, indicating Parameter 13 has been selected.

Page: 63

3. Press Switch 1 once for five seconds. The contents of the Parameter 13 register will be displayed.

4. To modify the contents of the Parameter 13 register, press Switch 1 (momentarily) to step through the addresses (in accordance with the chart shown below).

5. To end the adjustment, press Switch 1 once for five seconds. The LED will flash thirteen times, indicating Parameter 13.

LED Drive Time Rating / Drive Time Setting Table

Drive Time Rating displayed on LED Head

08 5

09 4

10 3

11 12 2

Drive Time Setting Value (Address)

13 14 1

15 16 17 0

18 19 20 15

21 22 23 24 14

25 26 27 28 29 13

30 31 32 33 34 35 36 12

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.3.06 Voltage Adjustment (+5 vdc)

Procedure

1. Remove the upper cover.

2. Remove the shield cover.

3. Remove the main controller board.

4. Use a digital voltmeter which has an input impedance of 10M Ohms and is capable of displaying to the second decimal place or farther.

5. Check the voltage at CN1 of the interconnect board (1) between Pin 31, 5 vdc and Pin27, 0 vdc .

The value should be +5.0 vdc (+/-0.1).

Page: 64

6. If adjustment is required, remove the font guide.

7. Change the output voltage by adjusting potentiometer RV1 on the power supply board (2).

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.3.07 Darkness Control

General Information

The Darkness Control is adjusted from the Level 2 Menu. This adjustment changes the degree of character density.

Procedure

1. Place the printer off-line.

2. Press and hold MENU more than 2 seconds. The first menu category will appear on the

display.

3. Press MENU until "Darkness" appears on the display.

4. Press "+" to toggle through the values until the desired setting is reached.

5. Press ENTER/MENU RESET to store the new setting.

Page: 65

Service Guide OL400

Chapter 3 Maintenance & Disassembly

3.4 CLEANING

3.4.01 General Information

Remove any dropped toner and dust. Clean inside and around the printer with a vacuum cleaner when necessary.

CAUTION: Do not touch the image drum, the LED head, or the LED head connector block.

3.4.02 Cleaning the Static Charge Wire

1. Turn OFF the power supply switch, and press the "OPEN" button and raise the stacker cover.

2. Push the two lock levers backward and lift the LED holder.

3. Clean the static charge wire by moving the blue wire cleaner of the image drum cartridge to the

left and right.

Page: 66

4. Place the blue wire cleaner in its original position (to the right).

3.4.03 Cleaning the Transfer Charge Wire

CAUTION: Do not press strongly when cleaning or you will break the transfer wire.

1. Push the two lock levers backward to lift the LED holder, and take out the wire cleaner.

2. Close the LED holder.

3. Raise the upper unit.

4. Clean the transfer charger by pressing the wire cleaner to the transfer charger assembly. Slide

it several times to the left and right, and clean the transfer wire.

5. Return the wire cleaner to its original position.

3.4.04 LED Lens Array

1. Clean the LED lens array when vertical white lines or "blank" spots appear on the output.

2. Place the LED lens cleaner pad against the LED lens array.

3. Slide the cleaner pad horizontally several times to clean the head. Use a clean area of the pad

on each pass.

4. Discard the pad.

Service Guide OL400

Chapter 4 Failure & Repair Analysis

4.1 OVERVIEW

4.1.01 Introduction

This section is used to isolate problems to the assembly level. Application problems and detection of faulty components on the printed circuit boards are not addressed.

Page: 67

When troubleshooting a defective unit, refer first to Section 4.4{ section contains tips on preventing problems as well as a list of common problems.

Next, refer to Section 4.5{ problems.

Finally, refer to Section 4.6 { require you to make observations. The answers to these questions and the results of your observations determine your next course of action. Use the RAP Index to identify which RAP should be used to resolve the problem with the machine.

If you encounter a situation that is not addressed by the documentation in this kit, please report the problem to Okidata. Refer to the Service Center Reference Guide for information on contacting Okidata.

The following information is provided to detect and analyze failures.

Okilink II, Faxable Facts, Technical Service Bulletins Troubleshooting Tips / Common Problems Fault Alarms Output Samples Repair Analysis Procedures* Tests Continuous Print Print Fonts Menu Print Serial Interface Loop Engine

}. This section lists the operator panel messages and sample output

}. Repair Analysis Procedures (RAPs) will ask you questions or

} of this Service Handbook. This

Service Guide OL400

Chapter 4 Failure & Repair Analysis

4.2 TROUBLESHOOTING UPDATES

4.2.01 General Information

Okidata distributes updated troubleshooting information in three ways.

Okilink II Faxable Facts Technical Service Bulletins

4.2.02 Okilink II

Okilink II is Okidata's Bulletin Board Service. This service is available to all Okidata Certified Service Technicians. Okilink II provides troubleshooting and service information. Technicians can download files, ask questions of Okidata's technical support personnel, and participate in round table discussions about Okidata products and services. Technical Service Bulletins, Recommended Spare Parts Lists, Printer Drivers, Product Specifications, and Service Training Information are also available.

Page: 68

Refer to the Service Center Reference Guide { } for information on accessing Okilink II.

4.2.03 Faxable Facts

Okidata's Faxable Facts is an automated fax document retrieval system. It is maintained by Okidata's Customer Information Center. Answers to common questions about Okidata products are available through Faxable Facts.

Refer to the Service Center Reference Guide{ } for information on accessing Faxable Facts.

4.2.04 Technical Service Bulletins

Okidata's Technical Service Bulletins (TSBs) contain technical information developed after product release. Firmware updates, part number changes, and procedural changes are some of the subjects covered by these bulletins. The TSBs are distributed through Okilink II.

Refer to the Service Center Reference Guide { } for information on accessing Okilink II.

Service Guide OL400

Chapter 4 Failure & Repair Analysis

4.3 REPORTING PROBLEMS

4.3.01 General Information

Okidata strives to provide accurate and detailed service information through its training materials. The Technical Training Group realizes that service technicians have valuable experience, knowledge, and opinions. Okidata strongly encourages you to report any problems you may encounter when using the materials of this training kit. Please be as specific and detailed as possible. Your comments, suggestions, and criticisms are used to update and revise training kits.

You should reference the training materials when servicing Okidata products. Most problems can be solved by using the information provided in the training materials. If you encounter a situation that cannot be solved, please let Okidata know.

Refer to the Service Center Reference Guide { } for information on contacting Okidata.

4.3.02 Problem Lists

Technicians frequently request a list of common problems specific to a product. Technical Training Kits are written before a product is shipped to customers. Therefore, such information is not available when a product is first released.

Page: 69

However, Okidata wants to respond to these requests. Okilink II provides round-table discussions on technical problems. Errors and corrections in the training materials are listed in the Training Section of Okilink II. The Technical Service Bulletins (also known as Okidata's Monthly Mail) are available via Okilink II. Situations that are not addressed in the reference documentation, technical service bulletins, or round tables may be reported to the Dealer Service and Support Engineers (DSSEs) or the Technical Training Group. You will receive a response to your message within one business day.

The information on Okilink II is the most accurate and up-to-date technical information available from Okidata. This is only possible with your assistance. By reporting your suggestions, concerns, and problems, Okidata can provide the best possible information.

Your cooperation is greatly appreciated. Thank you for your help!

4.3.03 Reporting Methods

Okilink II You may use Okilink II to report your findings. Refer to the Service Center Reference Guide for information on using Okilink II.

Course Critique Use the Course Critique to report any problems you find as you are completing the self-paced training.

Fax Number

If you wish to fax your response, please use the numbers listed in the Service Center Reference Guide.

Mailing Address If you respond by mail, please use the appropriate address listed in the Service Center Reference Guide.

Information Provided Please provide the following information when reporting problems.

Okidata Dealer Number Technician's Name Company Name Company's Address (Street, City, State/Province, ZIP / Postal Code, Country) Telephone and Fax Numbers (with area / country access codes) Product Name Unit's Serial Number Firmware Revision Level Description of Problem Document Name (with page number or procedure) with error or problem.

Service Guide OL400

Chapter 4 Failure & Repair Analysis

4.4 TROUBLESHOOTING TIPS

4.4.01 Preliminary Checks

Is the product being operated under the proper ambient conditions? Does the paper being used meet the specifications for this product? Have the consumables been replaced as recommended? Have the consumables been installed properly? Are Okidata consumables being used? Is the LED Head Drive Time correctly set? Check the contacts and connections of the power supply board. If good contact is not made at all

connections and ground points, false diagnosis will occur.

Page: 70

Examine the basic check points as directed in the Solutions manual. Gather as much information on the problem from the customer as possible. Perform inspections in conditions which resemble those in which the problem occurred.

4.4.02 Tips For Preventing Image Problems

1. Do not let anything touch the surface of the image drum.

2. NEVER

3. Do not touch the fuser unit. It is heated during operation. Oil from your skin may cause uneven

fusing temperature.

4. Do not expose the image drum to light for more than 5 minutes.

expose the image drum to direct sunlight.

Service Guide OL400

Chapter 4 Failure & Repair Analysis

4.5 FAULT ALARMS

4.5.01 General Information

The operator panel is used to display printer modes and error conditions. The table below shows the operator panel display and the mode or condition it matches.

Failure To Initialize At Power-On

If the printer fails to go ON-LINE at Power-On, refer to RAP 01.

LCD Error Message

The failure status of this printer is displayed on the liquid crystal display (LCD) in the operator panel. The Error Messages Table lists the problems that may be indicated by messages on the LCD. The first and the second lines of each LCD message are displayed alternately at 1 second intervals. The messages are displayed until the associated error(s) is removed.

Image Problems

If the printer output is faulty, refer to the Output Samples and determine which example resembles the problem. Proceed to the Repair Analysis Procedure (RAP) referred to by the example.

Page: 71

4.5.02 Error Messages Table

Page: 72

Service Guide OL400

Chapter 4 Failure & Repair Analysis

LCD Error Message

ON-LINE Ready to receive data in

OFF-LINE Printer idling in off-line mode Normal Operation

DATA PRESENT There is data to be received in

PRINT FONTS Font samples are being printed Normal Operation

PRINT MENU Menu is being printed Normal Operation

CONTINUOUS PRINT

LOOP TEST Testing serial interface circuit

Message Description Recommended

Action

Normal Operation

on-line mode

Normal Operation

on-line mode

Repeated self testing Normal Operation

Normal Operation

loop

RESET Printer is being reset Normal Operation

MENU RESET Menu reset to factory default Normal Operation

ERROR RECEIVE BUFFER OVERFLOW

ERROR PAGE BUFFER OVERFLOW

ERROR DLL BUFFER OVERFLOW

Receive buffer overflow Possible

handshaking problem

Page buffer overflow Page layout too

complex. More memory may help.

DLL buffer overflow Too many DLL

Fonts. More memory may help.

FONT CARD FONT NOT FOUND

The font card is not recognized by the printer

Install card properly or replace main controller

ERROR FONT CARD REMOVED ON-LINE

ERROR PRINT OVERRUN

ERROR PROGRAM ROM CHECK

ERROR FONT CARD CHECK

ERROR FONT ROM CHECK

ERROR EEPROM EEPROM error Press RECOVER.

Font card taken out during on-line

Printing overrun Page layout too

Program ROM error Replace Program

Font card error Replace defective

Font ROM error Replace Font

Printer must be OFF-LINE when changing font card

complex. More memory may help.

ROM on main controller PCB

card

ROM on main controller PCB

Replace EEPROM

ERROR RESIDENT RAM CHECK

ERROR OPTION RAM CHECK

ERROR LOOP TEST Error occurred during serial I/F

ERROR PRINTER I/F TIMEOUT

ERROR OP-PANEL I/F TIMEOUT

ERROR ENGINE FUSING PROBLEM

Resident RAM error Replace main

Option RAM error Replace optional

loop test

Error occurred during main controller board and engine controller board interfacing.

Error occurred during operator panel and engine control board interfacing.

Fusing temperature is higher or lower than the required value.

controller

RAM

Replace Serial I/F PCB

Replace main controller or engine controller

Replace operator panel or engine controller

Refer to RAP 05

ERROR ENGINE FAN PROBLEM

Engine fan motor error Replace DC Fan

or engine controller

ERROR ENGINE Engine error other than the

above two

WARMING UP Power has been turned on and

now warming up.

PAPER OUT TRAY Paper cassette has run out of

paper.

PAPER FEED JAM Paper jammed during feeding. Refer to RAP 02

PAPER JAM Paper jammed during

conveying.

COVER OPEN Upper cover is open. Close cover or

EXECUTIVE TRAY REQUEST

Request to set executive size paper cassette

Refer to RAP 06

Normal Operation

Add paper to cassette

Refer to RAP 03

check cover interlock switch

Normal Operation

LETTER TRAY REQUEST

LEGAL TRAY REQUEST

ENVELOPE TRAY REQUEST

EXECUTIVE PAPER MANUAL REQUEST

LETTER PAPER MANUAL REQUEST

LEGAL 14 INCH MANUAL REQUEST<_>

Request to set letter size paper cassette

Request to set legal size paper cassette

Request to set envelope cassette

Request to manually feed executive size paper

Request to manually feed letter size paper

Request to manually feed 14" legal size paper

Normal Operation

Load paper. Press

FORM FEED

Load paper. Press

FORM FEED

Load paper. Press

FORM FEED

LEGAL 13 INCH MANUAL REQUEST

Request to manually feed 13" legal size paper

Load paper. Press

FORM FEED

Monarch ENVELOPE MANUAL REQUEST

COM-10 ENVELOPE MANUAL REQUEST

DL ENVELOPE MANUAL REQUEST

C5 ENVELOPE MANUAL REQUEST

SIZE TRAY ERROR Printer on paper of

CHANGE DRUM Drum life has been attained Replace Drum Kit.

Request to manually feed monarch 7.314 envelope

Request to manually feed commercial 10 envelope

Request to manually feed Int'l DL envelope

Request to manually feed Int'l C5 envelope

non-requested size

Load paper. Press

FORM FEED

Load paper. Press

FORM FEED

Load paper. Press

FORM FEED

Load paper Press

FORM FEED.

Refer to RAP 04

Press RECOVER when turning the printer ON

Page: 73

Service Guide OL400

Chapter 4 Failure & Repair Analysis

4.5.03 Output Samples

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Service Guide OL400

Chapter 4 Failure & Repair Analysis

4.6 REPAIR ANALYSIS PROCEDURES

4.6.01 Using the RAPs

When using the Repair Analysis Procedures, follow these steps.

1. Use the RAP INDEX to find the RAP associated with the printer's problem.

2. Go to the appropriate RAP.

3. All of the RAPs will begin with a START Statement, followed by questions or another

type of statement.

4. If the RAPs do not lead you to the cause of a problem, please report this to Okidata.

Refer to Section 4.3 for further details{

Page: 74

4.6.02 RAP Index

Page: 75

Service Guide OL400

Chapter 4 Failure & Repair Analysis

RAP #

01 Printer Does Not Initialize ..... ( )

02 Paper Feed Jam Alarm ..... ( )

03 Paper Jam Alarm ..... ( )

04 Size Tray Error Alarm ..... ( )

05 Engine Error- Fusing Problem Alarm ..... ( )

06 Engine Error Alarm ..... ( )

07* Light or Blurred Image ..... ( )

08* Dark Background ..... ()

09* Blank Output ..... ( )

10* Vertical Black Stripes ..... ( )

11* Repeating Marks ..... ( )

12* Blank Spots ..... ( )

13* Vertical White Stripes ..... ( )

RAP Description

14* Black Page ..... ( )

15* Poor Fusing ..... ( )

* Refer to the Output Samples, 4.5.03 { }.

CAUTION:

In some of the RAPs, you will be asked to replace the image drum cartridge and then told to reset the drum counter by turning the printer ON while pressing the RECOVER switch.

DO NOT RESET THE DRUM COUNTER unless you replace the image drum cartridge.

Service Guide OL400

Chapter 4 Failure & Repair Analysis

RAP 01Printer Does Not Initialize

START

Turn the power OFF, then ON. Is the WARMING UP message displayed?

YES Go to B NO Check the AC cable connection.

Verify that +5V output is generated. Check the connection at the main controller circuit board CN1-1 (+5V) and CN1-3 (0V)

YES Go to A

Page: 76

NO Is the power fuse open?

YES Check for shorts between AC and replace the fuse NO Is power generated when the engine controller circuit board is detached

(from the power supply unit) and AC power is turned ON? YES Is there a short between +38V and 0V? Is there a short between

+5V and 0V when the engine controller board is installed. (Make this check on the engine controller board.) Be sure that the circuit side of the engine controller board is not touching the shield frame.

NO Replace the power supply unit. YES Install Engine Controller Board correctly.

Is the Block Character displayed on the operator panel 16 seconds after the power is turned ON?

YES Replace the main controller circuit board or the engine controller circuit board. NO Is the operator panel cable disconnected?

YES Connect the cable. NO Replace the operator panel board.

Is an alarm displayed?

YES Take suggested action for the alarm (Refer to the Error Messages Table, 4.5.02). NO Is the fan rotating?

YES Allow the unit to warm up and go ON-LINE. NO Replace the engine controller circuit board

END

Service Guide OL400

Chapter 4 Failure & Repair Analysis

RAP 02:Paper Feed Jam Alarm

START

Does a JAM alarm occur when the power is turned ON?

NO Go to A YES Is the paper at the resist sensor?

YES Remove the paper. NO Is the JAM alarm cleared by overriding the resist sensor on the engine

controller circuit board? YES Check the resist sensor lever for normal operation.

Page: 77

NO Replace the engine controller circuit board.

Is the paper actuating the resist sensor lever?

YES Run the Engine Drive Test. Does the resist roller turn? NO Replace the paper feed assembly.

NO Replace the engine controller board.

END

Okidata OL840, OL830, OL820, OL800, OL400 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual