Kyocera Mita FS-1900, Service Manual

Page: 166 / 224

6-16
FS-1900
Yes
No
Yes
No
No
Call service
4200:0123456
Print status page.
Turn power switch off.
Turn power switch on.
Print status page.
Remove and check
harness between
engine board (KP-864)
and laser scanner unit.
+24 V DC
at #1 pin of YC601
on APC board
(KP-742) ?
Yes
Yes
No
Replace harness between
engine board (KP-864)
and laser scanner unit.
OK?
Replace engine board
(KP-864). See page 5-22.
Replace engine board
(KP-864). See page 5-22.
Replace laser scanner
unit. See page 5-37.
Does
pin #4 (LASER*) of
YC601 on APC board
(KP-742) goes high and
then low?
Pin #8 (_PDIN*)
of YC601 on APC board
(KP-742) output pulse
signal*
1
?
*
1
: Pin photo diode sensor
[board KP-746] detecting
horizontal synchronization signal
Frequency: 2.7 kHz,
Low level width: 1.4
µ
s
Harness (S02404) scanner unit
and engine board (KP-864)
Engine board (KP-864) and scanner
unit (replace at the same time)
NOTE:
If the problem is not solved by
this flow chart replace the
following items:
Meaning Suggested causes Corrective action
Laser beam detection
failed. The pin photo
diode sensor [board]
(KP-746) does not
deliver a horizontal
synchronous
signal (PD*).
No laser beam due to the laser diode defect
(PD*).
Soiled or defective pin photo diode sensor.
Defective gate array U204 of engine board.
Improper connector insertion.
Defective harness between engine board and
laser scanner unit.
Follow the flow chart
below.
(11) 4200 - Laser scanner unit (Pin photo diode sensor) error