LG RH4820W Service Manual page 66

Recognition Fail Case 1:
CD-ROM Fail
Check pick-up read power
is 0.9~1.3mW?
YES
Does focus servo
operate normally?
YES
Check pick-up
RF signal IC107(Pin115)
RFO(TP115)is
500~1000mVpp?
YES
Check RFEQO waveform
(IC107 Pin 99)is
800~1200mVpp?
YES
Check after replacing IC202.
Is it OK?
YES
OK
NO
Go to "LD CHECK".
NO
Go to "Focus Servo is unstable".
NO
•Check the pick-up FFC and CN101.
•Replace the pick-up unit.
NO
Replace the IC107
NO
Go to "Tracking Servo is unstable".
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