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TROUBLESHOOTING
Turn power on.
Check power supply circuit.
NO PN807 PIN5, 6.2V
Is power on? PN807 PIN7, 5V
IC803 PIN 2, 3.3V
YES
NO NO
Does initial read work? Check the DISK turns Check the connector
PN801, PN802, PN809
YES
Check the Laser
YES
YES
Check the focus circuit
YES
Check the TRAKING circuit
NO
Does it play? Check the tracking servo circuit.
YES
NO
Does it output audio? Check the PN807 PIN1, 3
OK
- 2-3 -
Fails to initial read
NO Check the Voltage change of PN 809 NO Defective connector
Disc motor turns PIN20(OPEN, CLOSE) PN809
YES YES
Does RF waveform appear? Check the Data transmission from Defective connector
NO NO
IC801 Pin3 PN809 pin11 to CD DSP PN809, Defective
5V
MICOM
0V
YES
Check the Data transmission from Defective connector
PN809 pin13 to MICOM PN809, Defective
NO
5V
IC801
0V
YES
Check the change of SLDO 2V NO Defective IC801
Voltage(IC801 pin23) 1V
0V
YES
Check the change of SL +, 1.2V NO Defective IC802
YES SL - Voltage 0V
(IC802 pin 18, 19)
0.8V
YES Defective contact PN802
Does laser light? Defective PICK-UP
A
YES
Does FA+ waveform appear at
IC802 pin13? NO
focus coil drive wareform.
YES
Does TE waveform appear at
801 pin 15? NO
B
TRACKING ERROR wareform
YES
Is rotation normal?
NO
YES
Is there no dropout of RF signal?
Defective IC801
YES Defective PICK-UP
- 2-4 -
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
802 pin 17, 18? Defective IC 801, 802
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 PN802? 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)
R808