LG GWA-4164B Service Manual page 79

Recognition Fail Case 3 :
DVD Disc
Check Pick-up Read Power
was 1.1~1.3mW.
YES
Is there RF signal at IC121
Pin81?
YES
Is there
RF signal at IC121 Pin95(RFP)
and Pin96 (RFN)?
YES
Check again after the replace
IC121 It is OK?
YES
OK
Recognition Fail Case 4 :
Blank DVD+R/RW
Is there WBL
(IC121 pin63) Signal?
NO
Replace IC121.
NO
Go to 'LD CHECK'.
NO
Replace the Pickup.
NO
Replace the IC121.
NO
Replace the IC201.
YES
Is there WBL
(IC201 pin39) Signal?
Check the connection
between IC121 and IC201.
YES
NO
Replace IC201.
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