Upper frame assembly
B. Paper set sensors (PH1A, PH1B, PH1C)
7.3 Image Quality Troubleshooting
7.3.2 Image Issues
(1) Too light image (Only the halftone image)
(Print out Test Pattern No.1 and No.3 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
1 Was this problem cleared after basic image
adjustment is done? Yes OK
LED Head 2 Is the Lens Array of the LED Head dirty? Yes Clean it.
Copying media 3 Can you fix the problem if you use an newly
unpacked copying media? Yes 1. Since the copying media is humidified, advise your customer of proper way to store the copying media.
2. Explain to your customer that in case other than
recommended paper is used, there is a possibility that image quality gets worse a little.
Is the Image Corona dirty? Yes Clean the whole unit, or replace the Corona Wire with the new one.
Is the height of the Corona Wire proper? No Adjust it properly.
Image Corona 4
Is a proper power supplied to the Image
Corona? No Adjust or replace the High Voltage
Power Supply.
Pre-exposure Lamp 5 Does the Pre-exposure Lamp light up
correctly? No Check whether the connector is
connected or not to the Pre-exposure Lamp.
Or check or replace the Pre-exposure Lamp PCB.
Is the Transfer / Separation Corona dirty? Yes Clean the whole unit, or replace the Corona Wire with the new one.
Transfer / Separation
Corona 6
Is a proper power supplied to the Transfer
Corona? No Adjust or replace the High Voltage
Power Supply.
Contact Point of the
Developer Bias 7 Does the Contact Point of the Developer Bias
firmly touch the Developer Unit? No Contact it firmly to the Developer Unit.
Grease it with the electrically conductive grease.
Developer Bias Power
Supply 8 Can you fix the problem if you replace the Developer Bias Power Supply with the new one?
Yes OK.
Set Position of Developer
Unit 9 Is the pushing Cam of the Developer Unit
stopping at a correct position? No Check Cartridge Motor whether it is pushing Developer Unit properly.
Check Developer Pushing Cam.
Developer Unit 10 Is the Development Roller covered with the
toner evenly? No Check the Developer Unit for
finding out the cause.
11 Replace Photo Conductive Drum
(2) Too light image (Halftone and solid black)
(Print out Test Pattern No.1 and No.3 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
1 Does the image get better after basic image
adjustment is done? Yes OK
2 Turn the Main Switch off during printing cycle.
Then slide the Process Unit to right side in order to make Photo Conductive Drum free.
Check if the image on Photo Conductive Drum is normal before transportation.
No Skip to item 9
Is the Transfer / Separation Corona set firmly? No Set Transfer / Separation Corona firmly.
Transfer / Separation Corona
3
Is there a leaking on Transfer / Separation
Corona? Yes Clean the Transfer / Separation
Corona, and set it correctly.
Copying media 4 Can you fix the problem if you use a newly
unpacked copying media? Yes 1. Since the copying media is humidified, advise your customer of proper way to store the copying media.
2. Explain to your customer that in case other than
5 Does it have a proper resistance?
The resistance of the Lead Wire is approx.
10k-ohms.
No Replace the Lead Wire.
HV2 6 Is a proper voltage supplied to the Transfer
Corona? No Adjust or replace the High Voltage
Power Supply.
DC Controller 7 Is the signal confirmed properly? No Replace the DC Controller.
Transfer
Contact Point of the Developer Bias
8 Does the Contact Point of the Developer Bias
firmly touch the Developer Unit? No Contact it firmly to the Developer Unit.
Grease it with the electrically conductive grease.
9 Is the Development Roller covered with the
toner evenly? No Check the Developer Unit for
finding out the cause.
Developer Unit
10 Confirm if the Developer Unit is set properly.
(Confirm that Spacer Roller of Developer Unit is tightly contacted to Photo Conductive Drum.)
No Set Developer Unit properly.
Set Position of
Developer Unit 11 Is the pushing Cam of the Developer Unit
stopping at a correct position? No Check Cartridge Motor whether it is pushing Developer Unit properly.
Check Developer Pushing Cam.
Defective Develop-ment
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(3) Extremely light image (The whole image)
(Print out Test Pattern No.1 and No.3 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
1 Does the image get better after basic image
adjustment is done? Yes OK
2 Turn the Main Switch off during printing cycle.
Then slide the Process Unit to right side in order to make Photo Conductive Drum free.
Check if the image on Photo Conductive Drum is normal before transportation.
No Skip to item 9.
Development Driving System 3 Is the Development Roller rotating? No Check the Driving System of Developer Unit.
Is the Transfer / Separation Corona set firmly? No Set Transfer / Separation Corona firmly.
Transfer / Separation Corona
4
Is there a leaking on Transfer / Separation
Corona? Yes Clean the Transfer / Separation
Corona, and set it correctly.
Lead Wire of
HVP 5 Does it have a proper resistance?
The resistance of the Lead Wire is approx.
10k-ohms.
No Replace the Lead Wire.
HV2 6 Is a proper voltage supplied to the Transfer
Corona? No Adjust or replace the High Voltage
Power Supply.
DC Controller 7 Is the signal confirmed properly? No Replace the DC Controller.
Defective Transfer
Copying media 8 Can you get much darker image if you use a
newly unpacked copying media? Yes Use a new Roll.
Use a different type of material of Roll.
Developer Unit 9 Confirm if the Developer Unit is set properly.
(Confirm that Spacer Roller of Developer Unit is tightly contacted to Photo Conductive Drum.)
No Set Developer Unit properly.
In case you have removed the Process Cartridge before turning OFF the Main Switch, Spacing Roller might be not contacted on the Drum.
Lead Wire of
Developer Bias 10 Is the Lead Wire of Developer Bias connected
properly? No Connect the Lead Wire properly.
Developer Bias 11 Is a proper Developer Bias supplied to the Developer Unit? Check it during printing, or in the Service Mode.
No Check the Developer Bias Power Supply or contacts.
(Check both ON signal and Analog Input.)
Defective Develop-ment
DC Controller 12 Is the signal confirmed properly? No Replace the DC Controller.
(4) Different copy density
(Print out Test Pattern No.1 and No.3 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Is the Image Corona dirty? Yes Clean the whole unit, or replace the Corona Wire with the new one.
Image Corona 1
Is the wire height much different between both
sides? Yes Have a same height at both sides.
Set Position of Developer
Unit 2 Confirm if the Developer Unit is set properly.
(Confirm that Spacer Roller of Developer Unit is tightly contacted to Photo Conductive Drum.)
No Check the pushing system of Developer Unit.
LED Head 3 Is the LED Head dirty? Yes Clean it.
Pre-exposure Lamp 4 Are all lamps of Pre-exposure Lamp light up
during printing? No 1. Replace Pre-exposure Lamp.
2. Replace DC Controller.
Is the Development Roller covered with the
toner evenly? No Check if Regulation Roller is
cleaned properly..
Developer Unit 5
Check if toner in the Developer Unit is even. Yes Check the leveling of the machine.
K66sm7e3.doc (Ver. D.2) 7-32
(5) Totally appeared foggy image
(Print out Test Pattern No.1 and No.4 (White) for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
1 Does the image get better after basic image
adjustment is done? Yes OK
Developer Unit 2 Is the Development Roller insulated from the
ground? No Check the Development Roller and
the connector of Developer Unit.
Image Corona 3 Is the white paper also foggy, when white
paper is copied? Yes Check High Voltage Power Supply.
Developer Bias 4 Is a proper Developer Bias supplied to the Developer Unit? Check it during printing, or in the Service Mode.
No Check or replace the Developer Bias Power Supply.
DC Controller 5 Is the signal confirmed properly? No Replace the DC Controller.
Photo Conductive Drum 6 Have you used the Drum exceeding its part
life? Yes Replace the Drum with the new
one.
(6) Vertical blurred or foggy black wide line
(Print out Test Pattern No.1 and No.4 (White) for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Is the Image Corona dirty? Yes Wipe the Image Corona using Service Mode.
Or clean the whole unit, or replace the Corona Wire with the new one.
Does the Cleaning Pad stay at left side? No Confirm the movement using Service Mode 08-04.
Image Corona 1
Does the Cleaning Pad move properly?
(approx. 45 seconds for one way) No Replace PW6652 (Driver Board) or Image Corona Head.
Developer Unit 2 Is the Development Roller covered with the
toner evenly? No Check if Regulation Roller is
located properly.
External Light 3 Check if light from outside is affecting to the
Photo Conductive Drum Yes OK
(7) Vertical Clear Black Narrow Line
(Print out Test Pattern No.1 and No.4(white) for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Is there anything like a filament on the Grid Plate?
And does it touch the Drum?
Yes Remove it.
Image Corona 1
Is the Image Corona dirty? Yes Wipe the Image Corona using Service Mode.
Or clean the whole unit, or replace the Corona Wire with the new one.
Foreign Object is affecting. 2 Check if Foreign Object on Corona or LED Head is touching to the Photo Conductive Drum.
Yes Clean it.
Photo Conductive Drum 3 Is there any black line or any damage on the Drum, which corresponds with the position of the black line on the print?
Yes Clean off the black line.
Replace the Drum if it is damaged.
1. If it is scratched, confirm the
(8) Vertical White Line
(Print out Test Pattern No.1 and No.3 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Image Corona 1 Is there anything like a filament on the Grid Plate?
And does it touch the Drum?
Yes Remove it.
Dirty LED Head 2 Does this problem disappear, when the LED
Head is wiped. Yes OK
Transfer / Separation
Corona 3 Is there any foreign substance or dirtiness on
Transfer / Separation Corona? No Clean the Transfer / Separation Corona.
Developer Unit 4 Is the Development Roller covered with the
toner evenly? No Check the Regulation Roller.
Entrance of Fuser Unit 5 Is there any foreign substance or dirtiness Yes Remove it.
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(9) Void of image
(Print out Test Pattern No.1 and No.6 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
1 Make a half tone image using a Service Mode.
And check if white like is observed in the image.
No Jump to step 4.
Does it repeat approx. 157mm pitch? Yes 1. Clean up Counter Roller.
(For a gap between Drum and
Does it appear vertically mainly? Yes Check if Developer Unit has enough Toner.
Check Toner Sensor.
0V when “No Toner”.
(Service Mode “02-0C”)
Photo Conductive Drum 3 Does the defective image appear on the print
at intervals of about 250mm? Yes 1. Clean the “Drum”.
2. Replace if “Drum” is scratched.
(If it is scratched, confirm the cause of the scratch before replacement.)
Check if Transfer Guide is touched on Drum.
Check whether or not the Separation Finger is also damaged.
Copying media 4 Does this problem disappear when new paper
is used? Yes Use a newly unpacked copying
media.
Advise your customer of proper way to store the copying media.
(10) Dirt on the back of the copy
(Print out Test Pattern No.1 and No.4 (White) for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
1 Does the image get better after basic image
adjustment is done? Yes OK
Developer Unit 2 Check if Toner Receiver of Developer Unit is
full of toner. Yes Clean the Developer Unit.
Transfer Guide 3 Is the Transfer Guide dirty? Yes Clean it.
Then, check the gap between Transfer Guide and Drum.
(1.0mm).
Paper Feeder Unit 4 Is the Feeder Unit dirty? Yes Clean it.
And check where the toner spills out.
Check if Entrance Guide Plate is getting dirty. Yes Clean it.
Check if Shutter is dirty. Yes Clean it.
Fuser Unit 5
Check the dirtiness of Exit Roller, upper and
lower. Yes Clean them.
(11) Defective fusing
(Print out Test Pattern No.1 and No.3 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Does the temperature go high after Main
Switch is turned ON? No Refer to “Fuser problem” item.
Fuser 1
Is the fusing temperature proper? No Adjust it properly.
Fuser Unit
Agitation Fan 2 Does this problem start during printing? Yes Check the joint between Agitation Fan and motor. Tighten the screw.
Media
Selection 3 Is the Media Selector adjusted to the material
of the actually used copying media? No Adjust it properly.
Copying media
Humidity of the
paper 4 Can you fix the problem if you use a newly
unpacked copying media? Yes Since the copying media is humidified, advise your customer of proper way to store the copying media.
(12) Incorrect Image Placement, No Leading Edge
When the image white area exists at 3mm (+/- 2mm) from the leading edge, the printer is normal.
(Print out Test Pattern No.1 and No.6 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Paper Supply Roller
Paper Feeding Roller 1 Check if the life time of Paper Supply Roller or Paper Feeding Roller of the related deck is exceeding the expected life or not.
Yes In case it is exceeded the life time, replace to a new Roller.
Paper Gate Clutch (MC4) 2 Is the Paper Gate Clutch working properly
without slip? No Check or replace the Paper Gate
Clutch.
Leading Margin setting 3 Is the Leading Margin setting proper? No Check the setting value.
If it is not proper, adjust it.
(13) Jitter
(Print out Test Pattern No.1 and No.6 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Drum driving area and Photo
Conductive Drum 1 Does the jitter appear on the print at intervals
of about 251mm? Yes 1. Check both Drum Gear and
driving gears (80T and 50T).
2. Confirm scratch mark or foreign substances on the Drum edges, where contacts to the Counter
K66sm7e3.doc (Ver. D.2) 7-36
(14) Less sharpened image
(Print out Test Pattern No.1 and No.8 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Dirtiness of LED Head 1 Does this problem disappear if LED Head is
cleaned? Yes OK
Yes OK Position of LED Head 2 Does this problem disappear if LED Head is
mounted properly?
No Adjust the height using shims.
Transfer / Separation Corona 3 Does this problem disappear if Transfer /
Separation Corona is cleaned? Yes OK
(15) Uneven image vertically
(Print out Test Pattern No.6 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Image Corona 1 Is the Image Corona Head dirty? Yes Clean Image Corona.
Transfer / Separation Corona 2 Does this problem disappear if Transfer /
Separation Corona is cleaned? Yes OK
Does this problem disappear if LED Head is
mounted properly? Yes OK
Does this phenomenon show 1/3 of image? Yes Adjust the height using shims.
Position of LED Head 3
Does this appear every 8mm pitch? Yes Replace LED Head.
(16) Totally white (No image)
(Print out Test Pattern No.1 for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Developer Unit Pressure 1 Is the Developer Unit pressed to the Drum
during printing? No Check the pressure system of
Developer Unit.
Developer Unit Driving Area 2 Is Development Roller rotating during printing? No Check the driving system of the Developer Unit.
Developer Bias 3 Is the spring connected properly? No Make a good connection.
Is the connector connected firmly to the LED
Head? No Connect it firmly.
LED Head 4
Turn the Main Switch OFF during printing.
Shift the Process Unit to right side in order to make the Drum free.
And check if the image on the Drum is normal.
No Replace the LED Head.
Is the Corona Wire of the Transfer Corona
broken? Yes Replace the Corona Wire with the
new one.
Is the Transfer / Separation Corona set
properly? No Set the Transfer / Separation
Corona firmly.
Transfer / Separation Corona 5
Is the Transfer / Separation Corona leaking? Yes Check the Transfer / Separation Corona.
Is the connection of the Lead Wire correct? No Connect it properly.
Lead Wire of Transfer
Corona 6
Is the resistance of the Lead Wire correct?
(It is approx. 10-kohms, normally.) No Replace it.
HVP 7 Does this problem disappear if HVP is
replaced? Yes OK
DC Controller 8 Does this problem disappear if DC Controller is
replaced? Yes OK
(17) Totally black
(Print out Test Pattern No.1 and No.4 (White) for checking. If required, print out another pattern.)
Cause Checking
order Checking Item Result Treatment
Is the Corona Wire of the Image Corona
broken? Yes Replace the Corona Wire with the
new one.
Is the tension of the Corona Wire enough? No Replace the Corona Wire with the new one.
Image Corona and High
Voltage Power Supply 1
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