4000 - Laser Scanner Unit (Polygon Motor) Error - Kyocera FS-1900 Service Manual

(10) 4000 - Laser scanner unit (Polygon motor) error

Meaning
POLRDY* does not
go low within 20
seconds after
POLON*
goes low (When
starting) or within
16 seconds after
REGPAP signal goes
high (during printing).
Call service
4000:01234546
Turn power switch off.
Remove and check
harness between
engine board (KP-864)
and laser scanner unit.
OK?
Turn power switch on.
+24 V DC
at #33 pin of YC206
on engine board
(KP-864) ?
Print status page.
Does
pin #1 (POLCLK) of
YC206 on engine board
(KP-864) output
square-wave*
signal?
Yes
Suggested causes
Defective gate array U204 on the engine board.
Defective polygon motor.
Improper connector insertion.
Defective harness between laser scanner unit
and engine board.
NOTE:
Pins of YC206 connector are
crowded and tiny. When if
measuring signal, contact
measurement probe with pins of
YC206 connector accurately.
No
Replace harness between
Yes
engine board (KP-864)
and laser scanner unit.
No
Yes
No
1
1
* : 2.7165 KHz
Replace engine board
(KP-864). See page 5-22.
6-15
Corrective action
Follow the flow chart
below.
Print status page.
Does
pin #31 (POLON*) of
YC206 on engine board
(KP-864) goes high and
then low?
Yes
Print status page.
Does pin
#30 (POLRDY*)
of YC206 on engine board
goes low, after pin #31
(POLON*) of YC206
goes low?
Yes
Replace engine board
(KP-864). See page 5-22.
Replace laser scanner
unit. See page 5-37.
NOTE:
When If not solved this flow chart,
try to replace below items.
Harness (S02404) scanner unit
and engine board (KP-864)
Engine board (KP-864) and scanner
unit (replace at the same time)
No
No
FS-1900