SHARP XL520H
Manual de Servicio

XL-520H,520E/CP-520,520E
� LCD indication error.
Is +5V applied to the pin 8 (VDD) of IC701? No Is +5.6V applied to the emitter of Q704? Yes Yes Check the pattern between Q704 and IC704. Check the pattern between Q704 and CNS603.

No

Is +5V applied to the pin 38 (SYS STOP) of IC701? No Yes

Check the PWB pattern between the collector of Q702 and Q701.

Check the peripheral parts of IC701 and LCD701.

� Laser lighting failure.
Is +2.5V applied to the pin 42 of IC802? Does the laser come on when pattern cut between pin 21 of IC801 and pin 42 of IC802. Yes Yes No Check the PWB pattern between IC701 and IC802 (BUCK/CCE/ BUS0~3) Is approx. 2V applied to the collector of Q801. No Yes Check CNW802. If it is normal, the optical pickup is faulty. Check the peripheral parts of IC801 and Q801. If it is normal, the optical pickup is faulty.

No

� Focus failure.
Does the optical pickup move up and down when the disc is removed? Yes Is the following waveform ouput at the pin 11 (FEI) of IC801 when the disc is set?
Pin11 (FEI)

No

Check as stated in item "FOCUS SERVO SAWTOOTH WAVE FAILURE".

Check the periphery of IC801 and CNW802. is it normal? No Yes The optical pickup is faulty. Yes The periphery of IC801 or CNW802 is faulty.

Pin16 (FSO)

Yes

Pin6 (SBAD)

Is the waveform shown above input at the pin 50 (SBAD) of IC802? Yes IC801 is faulty.

Check the pattern between pin 6 of IC801 and pin 50 of IC802. No

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