LG GSA-H20A Service Manual page 76

Recognition Fail Case 1:
CD-ROM Fail
Check Pickup Read Power
was 1.3 ~1.7mW?
YES
Does Focus Servo
operate normally?
YES
Check Pickup
RF signal IC121(Pin83)
RFOUT was about 400mV?
YES
Check EQOUTP
waveform (IC121 Pin 65) was
about 400mV?
YES
Check after replacing IC201.
It is OK?
YES
OK
Recognition Fail Case2 :
Blank CD-R/RW
Is there WBL (IC121 pin63)
signal?
NO
Replace IC121.
NO
Go to "LD CHECK".
NO
Go to "Focus Servo is unstable".
NO
Check the Pick-up FFC and CN101.
Replace the Pick-up.
NO
Replace IC121.
NO
Go to "Tracking Servo is unstable".
YES
Is there WBL (IC201 pin36)
signal?
NO
Check the connection between
IC201 and IC121.
YES
Replace the IC201.
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