JVC KW-XC400 Service Manual page 17

5.3 Spindle section
Is the disk rotated?
NO
Is the voltage output at pin 15
and pin 16 of IC681?
NO
Is the voltage input at pin 26
of IC681?
NO
Is the voltage output at pin 41
of IC621?
NO
Is the power supply present
at pin 6, pin 15, pin 25, pin 39,
pin 43, pin 48, pin 51 and pin
64 of IC621?
NO
Check the connections of
CD8V power supply.
5.4 Tracking section
YES
Does the RF signal appear at
pin 19 of IC601?
YES
Check the spindle motor and
its wiring.
Is the power supply present
YES
at pin 10, pin 19 and pin 28
of IC681?
NO
Check the connections of
CD8V power supply.
YES
Check the connections
between IC681 and IC621.
YES
Check IC621.
When the disc is rotated
at first:
Approx. 1.2V
Is the tracking error signal
output at pin 11 of IC601?
NO
Check the circuits in IC601 or
the vicinity of IC601.
NO
Replace IC601 or repair the
malfunction connection point
YES
Is the RF waveform at pin
19 of IC601 distorted?
NO
Check the circuits in
the vicinity of IC601
or the pickup.
YES
Check IC681.
YES
Check IC601.
YES
Check the pickup and
its connections.
NO
YES
Proceed to the Tracking
section
(No.MA235)1-17