Canon GP160DF Service Manual page 253

Cause Steps
Shading cor- 11
rection
Poor connector 12
connection
(between the
CCD unit and
the image
processor
PCB)
CCD unit 13
Image proces-
sor PCB
2 Too Dark
Cause Steps
Dirty scanner
assembly
Automatic
shading correc-
tion
Cartridge
High-voltage
contact point
pin on the DC
controller PCB
Developing
bias
Image proces-
sor PCB
COPYRIGHT © 1999 CANON INC.
Checks
Is the trouble resolved when auto-
matic shading correction is per-
formed? (see page 13-9)
Is the flat cable which connects J208
on the image processor PCB and
the CCD unit properly connected?
Is the trouble resolved when the
CCD unit is replaced?
Checks
1 Is the trouble resolved when the
scanning lamp, reflecting plate, mir-
ror and lens are cleaned?
2 Is the trouble resolved when auto-
matic shading correction is per-
formed? (see page 13-9)
3 Is the trouble resolved when the car-
tridge is replaced?
4 Are problems occurring due to defor-
mity of the high-voltage contact point
pin (JH402) on the DC controller
PCB?
5 Is the trouble resolved when the DC
controller PCB is replaced?
CANON GP160 REV.0 FEB. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 13 TROUBLESHOOTING
Yes/No Action
YES End
NO Connect the cable firm-
ly.
YES End
NO Replace the image
processor PCB.
Yes/No Action
YES End
YES End
YES End
YES Repair it. When this is
not possible, replace
the DC controller PCB.
YES End
NO Replace the image
processor PCB.
13-19