@
Proceed to the feed circuit flowchart .
i
•
I
NO
Does the pickup lens move
up
and down
NO
Is IC404-@
QY'.'
after SW401 is set to ON from OFF?
YES
lYES
Proceed to the focus circuit flowchart.
ls the laser lit for about 2 seconds after
NO
SW401
is
set to ON from OFF? (Check the
laser power meter becomes
90-120
J1
W)
n_
Does
IC404-®
become
OY
from
SY
for
N
0
about 2 seconds after SW401
is
set to ON
,__
YES
from OFF?
'
!YES
Is
focus engaged for about 2 seconds after
NO
SW40!
is
set to
ON
from OFF? (Check the
-
Check Q401
's
peripheral circuits, the 8-pin
I
lens movement visually.)
cable and pickup.
YES
'
Proceed to the disc circuit flowchart.
Does IC404-@ become
OY
from
SY
for
N
0
about 2 seconds after SW401
is
set to
ON
r-
from OFF?
Proceed to the focus circuit flowchart.
f-
l
YES
Check the connections
of
IC402-®
.
IC404 faulty
8-1. Focus Circuit Flowchart
Are
IC409-Q)/@/@9Y'.'
YES
Remove the top cover.
Set SW401 to ON to tum the power
on and check that the pickup lens
moves
up
and down.
YES
Does the waveform shown below
appear at
TP-Xl
when SW401
is
set to ON from OFF?
Yref
.............
Approx.
4Yp-p
· '
Approx.
O.Sms
Solid line: When focus is engaged.
Dotted line: When focus
is
not
engaged
YES
Check focus circuit IC403.
12
NO
1---~
Check the power circuit.
NO
Docs the waveform shown below
appear berween IC409-(J)
and@
i---~
(FD).
Approx. 7V
-
/\-71·1·
OY
1L----~----~--
-
FD : Focus Drive
YES
Check the connection with the
pickup .
NO Check the pickup (dirt on lens, laser
is
output) and tracking circuit IC402.
t
NO
Does the waveform shown below
appear berween IC403-(J) and
®
.------.
(FEO).
Pin@
Yref
Approx. 3Y
-
A·.7l1-·
-V
....
~--
·
=-
..
FEO
: Focus Error Out
YES
Check the path berween IC403-@
and IC409-
® .
IC403 faulty.
NO
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