Signal - Kyocera FS-1920 Service Manual

Code
4200 Laser scanner unit (Pin photo diode
sensor) error
• Laser beam detection failed. The pin
photo diode sensor [board] (KP-1075)
does not deliver a horizontal synchronous
signal (PD*).
Turn power switch off.
Remove and check
harness between
engine board (KP-1081)
and laser scanner unit.
Turn power switch on.
+24 V DC
at #1 pin of YC601
on APC board
(KP-1062) ?
Print status page.
pin #4 (LASER*) of
YC601 on APC board
(KP-1062) goes high
and then low?
Contents
NOTE:
START
If the problem is not solved by
this flow chart replace the
following items:
Harness (S03012 ) laser
scanner unit and engine board
(KP-1081)
Engine board (KP-1081) and
laser scanner unit (replace at
the same time)
No
OK?
Yes
Replace harness between
engine board (KP-1081)
and laser scanner unit.
No
Yes
Does
No
Yes
Causes
No laser beam
due to the laser
diode defect
(PD*).
Soiled or defec-
tive pin photo di-
ode sensor.
Defective gate
array U7 of en-
gine board.
Improper connec-
tor insertion.
Defective har-
ness between en-
gine board and
laser scanner unit.
Replace engine board
(KP-1081). See page 1-6-
20.
Remarks
Check procedures/corrective measures
Follow the flow chart below.
Print status page.
Pin #8 (_PDIN*)
of YC601 on APC board
(KP-1062) output pulse
1

signal*

Yes
Replace engine board
(KP-1081). See page 1-6-
20.
Replace laser scanner
unit. See page 1-6-35.
1
* : Pin photo diode sensor
[board KP-1075] detecting
horizontal synchronization signal
Frequency: 2.7 kHz,
Low level width: 1.4 ms
2FP/2FY/2FR
No
?
1-5-7