1-22
KD-LH7R
Feed Section
Focus Section
Tracking Section
Spindle Section
Is the voltage output at
IC621 pin "40" 5V or 0V?
Check the feed motor.
Is 4V present at both
sides of the feed motor?
Is the wiring for IC621
(56) ~ (64) correct?
Check IC681.
Is 6V or 3V present at
IC681 "4" and "5"?
Is 3.3V present at
IC681 pin "20"?
Check the feed motor
connection wiring.
Check the vicinity of
IC621.
Check CD 8V
and 5V.
YES
YES
YES
NONO
NO
NO
NO
YES
YES
When the lens is
moving:
Check the circuits in the
vicinity of IC681 pins
"8","9" and "15".
Check the pickup and
its connections.
NO
YES
YES
YES
Does the S-search
waveform appear at
IC681 pins "10" and "11"?
Is the disk rotated?
Does the RF signal
appear at TP1?
Is 4V present at IC681
pins "7" and "6" ?
Check the spindle motor
and its wiring.
Is 4V present at IC621
pin "41" ?
Check the vicinity of
IC681.
Check IC621 and
IC601.
YES
NO
NO
NO
NO NO
YES
YES
YES
Check the circuits in the
vicinity of IC601 "19"~"24"
or the pickup
Is the RF waveform at TP1
distorted?
Proceed to the Tracking
section
When the disc is rotated
at first:
Check the circuit in the
vicinity of IC601 pins
"2" ~ "12".
Check IC621.
Check the pickup and
its connections.
YESYES
YES
Is the tracking error signal
output at IC601 "11"?
Approx. 1.2 V
4V
w
w
w
.
x
i
a
o
y
u
1
6
3
.
c
o
m
Q
Q
3
7
6
3
1
5
1
5
0
9
9
2
8
9
4
2
9
8
T
E
L
1
3
9
4
2
2
9
6
5
1
3
9
9
2
8
9
4
2
9
8
0
5
1
5
1
3
6
7
3
Q
Q
TEL 13942296513 QQ 376315150 892498299
TEL 13942296513 QQ 376315150 892498299
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