JVC KD-S821R Service Manual page 13

Feed Section
Is the voltage output at
IC541 pin "53" 5V or 0V?
YES
Is 4V present at both
sides of the feed motor?
YES
Check the feed motor.
Focus Section
When the lens is
moving:
4V
Does the S-search
waveform appear at
IC501 pins "6" and "7"?
Spindle Section
Is the disk rotated?
YES
Does the RF signal
appear at TP1?
YES
Is the RF waveform at TP1
distorted?
YES
Proceed to the Tracking
section
Tracking Section
When the disc is rotated
at first:
Approx. 1.2 V
Is the tracking error signal
output at IC521 "12"?
YES
Check IC521.
NO
Is the wiring for IC541
(90) ~ (100) correct?
NO
NO
Is 6V or 2V present at
IC501 "10" and "11"?
NO
Check IC501.
NO
Check the circuits in
the vicinity of IC501
pins "14" ~ "18".
YES
YES
Check the pickup and
its connections.
NO
Is 4V present at IC501
pins "8" and "9" ?
YES
Check the spindle motor
and its wiring.
NO
Check the circuits in the
vicinity of IC521 "2" ~ "7",
NO
"18"~"24" or the pickup
YES Check the circuit in the
vicinity of IC521 pins
"2" ~ "12".
YES
Is 5V present at IC501
pin "20"?
YES
Check the vicinity of
IC541.
YES
Check the feed motor
connection wiring.
NO
Is 4V present at IC541
pin "55" ?
YES
Check the vicinity of
IC501.
YES Check the pickup and
KD-S821R
NO
Check CD 9V
and 5V.
NO
Check IC521 and
IC541.
its connections.
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