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NO
Is the Power ON?
YES
NO
Is the LCD normal?
YES
NO
ls the feed motor
at the correct initial
position?
YES
NO
Is the disc motor
rotating?
YES
NO
Does focusing
work?
YES
65
TROUBLESHOOTING
NO
s the voltage at
D/D OUT point
correct?
YES
Check U403 and reset
circuit Q4.
Check the OPEN/
CLOSE SW and micro-
processor IC U403.
Check the feed motor
control circuit, U301,
U302, U352, and U403
and the limit SW.
Check CLV circuit
U301, U352 and
U403.
NO
%
|
is laser beam
emitted?
YES
YES
* 2
Does the focus
search work?
NO
Check focusing control
circuit U301, U351
and U403.
For notes with an asterisk (>) in the above diagram, refer to page 64.
NO
Check U1, Q2 and Q3.
(In case of battery
Is the D/D con-
verter circuit
normal?
operation, check U901,
Y902, Q901
and
Q903
YES
Check power supply
switch Q805 to 0808,
Q401 and Q402.
Check RF amp U101,
NO
servo control U301
and
Is the LD-APC
circuit normal?
microprocessor U403.
YES
Check the laser pickup
and replace if required.
Check LD-APC circuit
U403, U101 and Q101.
66
Can the TOC be
read?
YES
NO
Is playback possi-
ble?
YES
NO
Is sound heard?
YES
NO
TROUBLESHOOTING
Is the eye-
pattern wave-
form normal?
YES
x 4
Is the limit SW
normal?
NO
YES
,
NO
!s the feed servo
circuit normal?
YES
NO
Is the muting
circuit normal?
YES
Check audio circuit
U404, U501 to U503,
Q501 and Q503.
For notes with an asterisk (3x) in the above diagram, refer to page 64,
NO
NO
Is the tracking
circuit normal?
YES
Check PLL servo circuit
U301
and U401.
Adjust the limit SW
position.
Check feed servo
circuit U301.
Check muting circuit
U403,
Q504,
Q505
and Q506.
Check tracking servo
circuit U101, U301
and U351.
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