LG OK75 - Electrical Troubleshooting: CD Function Check

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ELECTRICAL TROUBLESHOOTING GUIDE
8. CD FUNCTION CHECK
CD FUNCTION
Is motor_open/close ok?
(IC400 pin6, 7)
Replace cristal (X400).
Check loading motor.
Check IC400.
Check IC400 (Motor drive IC).
Is the MD (PN401 pin22)
about 190 mV?
Check MD (pick-up).
IM driving
(Focus and tracking) is ok?
Check Vcc of IC401.
Replace IC501.
Check cristal (X400).
Is motor ok? (about 12 Ω)
Is no signal at speaker?
Can the
disc insert?
Disc reading
is ok?
Check
the signal of IC401.
Check IC501
input/output and
control line.
Check
the signal (16.9344 MHz)
at IC401 pin49.
Focus,
tracking, sled signal
is ok?
Is load +,- ok?
NO
NO
NO
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
YES
NO
Refer to function check.