(No.MA147)1-27
SECTION 5
TROUBLESHOOTING
5.1
Feed section
5.2
Focus section
5.3
Spindle section
5.4
Tracking section
Check the feed motor.
Is 4V present at both
sides of the feed motor?
Is the wiring for IC621
pin 40 correct?
NO
YES
YES
Is the voltage output at
IC621 pin 40?
NO
Is 6V or 2V present at
IC681 pins 17 and 18?
NO
Check IC681.
YES
YES
Is 5V present at IC681
pin 6?
Check the feed motor
connection wiring.
YES
Check the vicinity of
IC621.
NO
Check CD 8V.
NO
When the lens is
moving:
Check the circuits in
the vicinity of IC681
pins 1 and 2.
Does the S-search
waveform appear at
IC681 pins 13 and 14?
4V
YES
NO
YES
Check the pickup and
its connections.
Is the disk rotated?
YES
NO
Is 4V present between
IC681 pins 15 and 16?
NO
Is 4V present at IC621
pin 41?
NO
Check IC621.
Does the RF signal
appear at IC601 pin 19?
YES
YES
Check the spindle motor
and its wiring.
Is the RF waveform
at IC601 pin 19 distorted?
YES
Proceed to the Tracking
section
Check the circuits in
the vicinity of IC601
or the pickup.
NO
NO
YES
Check the vicinity of
IC681
When the disc is rotated
at first:
Approx. 1.2V
Is the tracking error
signal output at IC601
pins 10 and 11?
YES
Check IC621.
Check the circuits in
the vicinity of IC601
pins 2 to 12.
NO
Check the pickup and
its connections.
NO
