Call Service 4200 - Laser Scanner Unit [Pin Photo Diode] Error - Kyocera FS-1050 - B/W Laser Printer Service Manual

(5) Call service 4200 - Laser scanner unit [Pin photo diode] error

Call service
4200
+5 V DC at pin 6 of
YC07 on main board
(KP-888) ?
Yes
Connect oscilloscope to
pin 4 (OUTPEN) of YC07
on main board (KP-888).
Turn power switch off,
then on.
Does
pin 4 (OUTPEN) of
YC07 on main board
(KP-888) goes high,
then low before
"4200" ?
Yes
Connect oscilloscope to
pin 4 (OUTPEN) and
pin 8 (PDN) of YC07 on
main board (KP-881).
Turn power switch off,
then on.
FS-1050
No
Replace main board
(KP-888). See page 5-12.
Replace main board
(KP-888). See page 5-12.
Turn power switch on.
OK?
No
End.
main board (KP-888) output
pulse signal*, within 0.1 second
after pin 4 (OUTPEN) goes
*: Pin photo diode
detect horizontal
synchronization signal
(Frequency: 1700 Hz,
Low level width: 10 µs)
6-12
Replace engine board
(KP-882). See page 5-11.
No
Turn power switch on.
Yes
Does pin 8
(PDN) of YC07 on
high, then
low?
No
B
Continued
to next page.
No
OK?
Yes
End.
Replace main board.
See page 5-12.
Yes
C
Continued
to next page.