Canon GP405 Service Manual page 472

CHAPTER 14 TROUBLESHOOTING
22 The copy is solid black.
Cause
Scanning lamp
Margin
Drum
Primary charging
assembly
Mirror
DC controller
PCB
Composite power
supply PCB
Image processor
PCB
CCD unit
14-54
Step Check
1 Does the scanning lamp remain on
during copying operation?
2 Is there a margin on copies made
normally?
3 Is the drum set correctly? (Is it fully
pushed in?)
4 Are the connection and continuity
(connectors and harness) from
J205-3 on the composite power
supply PC to the primary charging
assembly normal? (The resistance
on the primary charging high-
voltage cord must be about 10 KΩ.)
5 Generate test prints (1 through 8 of
PG>TYPE). Is the image on the
photosensitive drum normal?
6 Is the output (HVPDC*) of J103-
B4 (+) of the DC controller PCB 0
V during copying operation?
7 Execute FUNCTION>MISC-P>IP-
CHK in service mode. Does it end
in 'OK'?
COPYRIGHT © 1999 CANON INC. CANON 405/335 REV.0 JAN. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Yes/No Action
NO See "The scanning lamp
fails to turn on."
YES Go to step 6.
NO Go to step 3.
NO Correct the mounting.
NO Correct the connection.
NO Go to step 7.
NO Replace the DC
controller PCB.
YES Replace the composite
power supply PCB.
NO Replace the image
processor PCB.
YES Check the wiring of the
flat cable; if normal,
replace the CCD unit.