Konica Minolta bizhub C658 Service Manual page 1649

bizhub C658/C558/C458/C368/C308/C258
(5) Scanner troubleshooting procedure
Step Section
1 Original
2 Original Type
3 Basic -> Density
4 When DF is being used
5 When original glass is
being used
6 Parts along scanning
path
7 Main body side_shading
sheet
8 • When DF is being
used: 1st side
• When DF-629 is
being used: 2nd side
9 DF-704 or dual scan
document feeder is being
used: 2nd side
16.3.12 Void areas, White spots
(1) Typical faulty images
The arrow in the exemplary image troubles indicates the paper feeding direction.
[1]
[1] Void areas
(2) Initial troubleshooting procedure
Step Section
1 Paper Setting
2 Use in areas with low
atmospheric pressure
3 IDC sensor
4 Service Mode ->
Stabilizer
5 Service Mode ->
Gradation Adjust
6 Service Mode -> Charge
AC Output fine
adjustment
Check item
Original is damaged or dirty.
Select [Copy setting] -> [Original Type] and change the
setting, and the image trouble is eliminated.
Change the density setting, and the image trouble is
eliminated.
DF does not lie flat.
Original glass or original pad is dirty.
Mirror, lens, light guide or reflectors is dirty.
Shading sheet of main body is dirty.
Original reading glass or original reading glass cleaning
brush is dirty.
• Shading correction surface of DF-704 or dual scan
document feeder is dirty.
• CIS glass or CIS cleaning brush is dirty.
[2]
Check item
The paper to be used for printing does not match the
paper type and size of paper setting selected on the
machine.
Select [Service Mode] -> [Imaging Process Adjustment]
-> [Grad/Dev AC Bias V Selection] and change the
setting to [ON]. This eliminates the trouble.
• IDC sensor is dirty.
• IDC sensor shutter does not operate properly.
Select [Service Mode] -> [Imaging Process Adjustment]
-> [Stabilizer] -> [Stabilization
trouble is eliminated.
Select [Service Mode] -> [Imaging Process Adjustment]
-> [Gradation Adjust] and the image trouble is
eliminated.
The white spots is eliminated when [Service Mode] ->
[Imaging Process Adjustment] ->
fine adjustment] are selected and the setting value is
increased.
K-321
K TROUBLESHOOTING > 16. IMAGE QUALITY PROBLEM
Result
YES
NO
NO
YES
YES
YES
YES
YES
NO
YES
NO
[2] White spots
Result
YES
NO
YES
NO
Only] and the image
NO
NO
[Charge AC Output
Action
Change the original.
Go to the next step.
Go to the next step.
• Adjust the DF height.
(DF-704 / DF-629 / Dual scan
document feeder)
• Replace DF if it is deformed
or hinges are broken.
Clean.
Clean.
Clean.
Clean.
• Replace the LED exposure
unit. (bizhub C368/C308/
C258 / bizhub C658/C558/
C458)
• Replace the CCD unit.
(bizhub C368/C308/C258
bizhub C658/C558/C458)
Clean.
Replace the CIS module. (bizhub
C368/C308/C258 / bizhub C658/
C558/C458)
Action
Make the paper setting again on
the machine.
Change the setting to [OFF] and
go to the next step.
• Clean.
• Clean or correct the IDC
sensor shutter.
Go to the next step.
Go to the next step.
Return the setting value to the
original one and go to the next
step.
/