KD-S747
1-24 (No.49822)
3.2 Troubleshooting
3.2.1 Feed section
3.2.2 Focus section
3.2.3 Spindle section
3.2.4 Tracking section
Is the voltage output at
IC521 pin u 5V or 0V?
Check the feed motor.
Is 4V present at both
sides of the feed motor?
Is the wiring for IC521
(90) (100) correct?
Check IC581.
Is 6V or 2V present at
IC581 Q and R?
Is 5V present at IC581
pin 6?
Check the feed motor
connection wiring.
Check the vicinity of
IC521.
Check CD 9V
and 5V.
YES
YES
YES
NO
NO
NO
NO
YES
YES
When the lens is
moving:
Check the circuits in
the vicinity of IC581
pins H K.
Check the pickup and
its connections.
NO
YES
YES
Does the S-search
waveform appear at
IC581 pins H and I?
4V
Is the disk rotated?
Does the RF signal
appear at TP1?
Is 4V present between
IC581 pins 1 and 2?
Check the spindle motor
and its wiring.
Is 4V present at IC521
pin x?
Check the vicinity of
IC581.
Check IC501 and
IC521.
YES
NO
NO
NO
NO
NO
YES
YES
YES
Check the circuits in the
vicinity of IC501 J O 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 IC501 pins
2C.
Check IC521.
Check the pickup and
its connections.
YES
YES
YES
Is the tracking error
signal output at TP3?
Approx. 1.2 V