Sharp XL-3000V service manual Laser failure, Focus failure

Models: XL-3000V

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XL-3000V

• Laser failure.

Is +6.2V applied to the emitter of Q861 ?

Yes

Is +5V applied to the collector of Q861 ?

Yes

Is +5V applied to the pin 62 (VDD) of IC802 ?

Yes

Is +5V applied to the pin 1 (VCC) of IC801 ?

Yes

Is 0V applied to the pin 57 (SEL) of IC802 ?

Yes

No

 

 

Check the PWB pattern between emitter of Q607 and emitter of

 

No

 

Q861.

 

Check the peripheral parts of IC804 and Q861.

No

 

 

 

Check the PWB pattern between collector of Q861 and pin 62 of

 

 

No

 

 

IC802.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Check the PWB pattern between collector of Q861 and pin 1 of

 

 

No

 

 

IC801.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Does the laser come on when pattern cut between pin 8 (SEL) of

 

 

No

 

 

IC801 and pin 57 (SEL) of IC802 ?

 

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

Check the PWB pattern between IC701 and IC802 (BUCK/CCE/

 

 

 

BUS0~3)

 

 

 

 

 

 

Is approx. 2V applied to the collector of Q801.

Yes

Check CNP802/CNW3. If it is normal, the optical pickup is faulty.

• Focus failure.

Does the optical pickup move up and down when the disc is removed?

Yes

Is the following waveform output at the pin 43 (FEI) of IC802 when the disc is set?

Yes

pin 43 (FEI)

pin 48 (FOO)

pin 44 (SBAD)

Is the waveform shown above input at the pin 44 (SBAD) of IC802?

Yes

No

Check the peripheral parts of IC801 and Q801. If it is normal, the

optical pickup is faulty.

No

Check as stated in item "FOCUS SERVO SAWTOOTH WAVE

FAILURE".

Check the periphery of IC801 and CNP802/CNW3. Is it normal? No

Yes

The optical pickup is faulty.

No

Check the pattern between pin 13 of IC801 and pin 44 of IC802.

Check the periphery of IC801 and CNP802/CNW3.

IC801 is faulty.

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Page 44
Image 44
Sharp XL-3000V service manual Laser failure, Focus failure