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TROUBLESHOOTING
Turn power on.
NO Check power supply circuit.
Is power on? (Check PN 807)
YES
NO
Does initial read work? Check laser circuit.
YES
Check focus circuit.
Check disc.
NO
Does it play? Check tracking servo circuit.
YES
NO
Does it output audio? Check audio circuit.
YES
OK
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Fails to initial read
NO
Disc motor turns. NO Does laser light? A
YES
YES B
Does RF Does tracking Does signal Does TE2 signal
NO NO NO NO
waveform servo work? appear at appear at pin Defective IC
appear? Lower envelope TP801(TEO)? of IC801? 801, pick up
TP 801(RF) of TP801(RF) and/or open
waveform is flat. wire.
1.3V
YES YES
YES Detective pattern.
Does signal appear at IC 803
Pin and Pin ? NO Defective IC 801
and/or IC 803
YES Defective pick-up
and/or connector.
Is rotation normal? NO Does GFS (IC802 pin ) NO
show as below? Defective IC 801.
YES
Is there no dropout of RF Scratch in disc
NO
signal? initial read area.
Defective pick-up
YES adjustment focus offset.
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A Laser does not light.
Is