1-13
KD-S723R/KD-S721R
Feed Section
Focus Section
Spindle Section
Is the voltage output at
IC541 pin "53" 5V or 0V?
Check the feed motor.
Is 4V present at both
sides of the feed motor?
Is the wiring for IC541
(90) ~ (100) correct?
Check IC501.
Is 6V or 2V present at
IC501 "10" and "11"?
Is 5V present at IC501
pin "20"?
Check the feed motor
connection wiring.
Check the vicinity of
IC541.
Check CD 9V
and 5V.
YES
YES
YES
NO
NO
NO
NO
NO
YES
YES
When the lens is
moving:
Check the circuits in
the vicinity of IC501
pins "14" ~ "18".
Check the pickup and
its connections.
NO
YES
YES
YES
Does the S-search
waveform appear at
IC501 pins "6" and "7"?
Is the disk rotated?
Does the RF signal
appear at TP1?
Is 4V present at IC501
pins "8" and "9" ?
Check the spindle motor
and its wiring.
Is 4V present at IC541
pin "55" ?
Check the vicinity of
IC501.
Check IC521 and
IC541.
YES
NO
NO
NO
NO
NO
YES
YES
Check the circuits in the
vicinity of IC521 "2" ~ "7",
"18"~"24" or the pickup
Is the RF waveform at TP1
Check the circuit in the
vicinity of IC521 pins
"2" ~ "12".
Check IC521.
Check the pickup and
its connections.
YES
YES
YES
Is the tracking error signal
output at IC521 "12"?
Approx. 1.2 V
4V
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