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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
- 10 -
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 53 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 26 and Pin 27 ? NO Defective IC 801
and/or IC 803
YES Defective pick-up
and/or connector.
Is rotation normal? NO Does GFS (IC802 pin 25) 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.
- 11 -
A Laser does not light.
Is "3.5V" applied to pin 70 of IC 801?
YES NO
NO NO
Did pickup return to Is data transferred from Defective MICOM.
innermost circular? MICOM IC ?
YES YES
Does voltage appear at IC NO
803 pin 11, 12? Defective IC 801, 803
YES Defective slide motor and/or
connector.
Does it stop at inner pick Is defect output from LM
circular after shift? SW applied to pin 2 of
YES PN803? NO Defective LMT SW and/or
connector.
OPEN CLOSE
YES Defective MICOM.
YES
NO
Is power supplied to laser Q801? Defective connector.
(Q 801 collector: about 1.8V)
R801