CD-MD3000 (serv.man7). Trouble shooting guide - Sharp Audio Service Manual (repair manual)

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When the CD section does not operate when the objective lens of the optical pickup is dirty, this section may not operate. Clean
the objective lens, and check the playback operation. When this section does not operate even after the above step is taken, check
the following items.
Remove the cabinet and follow the troubleshooting instructions.
"Track skipping and/or no TOC (Table Of Contents) may be caused by build up of dust other foreign matter on the laser pickup
lens. Before attempting any adjustment make certain that the lens is clean. If not, clean it as mentioned below."

Turn the power off.
Gently clean the lens with a lens cleaning tissue and a small amount of isopropyl alcohol.
Do not touch the lens with the bare hand.

Dust gradually accumulates on the objective lens during use, and it may degrade performance.  To avoid this problem, use a
cleaning disc designed for CD optical pickup lenses.

HOW TO USE
1. Using the brush in the cleaner cap, apply 1 or 2 drops of the cleaning fluid to the brush on the CD cleaner disc which has

the 

 mark next to it.

2. Place the CD cleaner disc onto the CD disc tray with the brush side down, then press the play button.
3. You will hear music for about 20 seconds and the CD player will automatically stop.  If it continues to turn, press the stop
button.
CAUTION

 The CD lens cleaner should be effective for 30~50 operations, however if the brushes become worn out earlier then please

replace the cleaner disc.

 If the CD cleaner brushes become very wet then wipe off any excess fluid with a soft cloth.

 Do not drink the cleaner fluid or allow it to come in contact with the eyes.  In the event of this happening then drink and /

or rinse with clean water and seek medical advice.

 The CD cleaner disc must not be used on car CD players or on computer CD-ROM drives.

 All rights reserved. Unauthorized duplicating, broadcasting and renting this product is prohibited by law.

Cleaner Liquid

Cleaning Disc
PARTS CODE: UDSKA0004AFZZ

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STEP 1

Does the display "E-CD01" appear?

Yes

No

Does the pickup move to the inner/outer position using the
'UP'/'DOWN' key?

Yes

STEP 2

Laser ON?

Check from pins 7 and 8 of CNP5 via Q4 and pins 6 and 7 of
IC6 to pin 38 of IC2.

Yes

STEP 3

Focus search?

Yes

STEP 4

No

No

No

Check from pins 5 and 6 of CNP6 via pins 19, 20 and 21 of
IC5 to pin 41 of IC2.

No

Tracking servo?

Yes

No

Check from pins 21, 22 and 23 of IC6 to pin 24 of IC2.

No

Yes

Yes

Check the line of PU-IN SW.

Check from pin 2 of CNP6 via pin 25 of CNP1 to pin 94 of
IC901.

Check the line of the slide control.
Check from pins 3 and 4 of CNP6 via pins 17, 18 and 22 of
IC5 to pin 40 of IC2.

Focus search?

STEP 5

Check from pins 1 and 2 of CNP5 via pins 3, 4 and 5 of IC5 to
pins 31 and 34 of IC2.
Check from pins 2 and 5 of CNP7 to pins 4 and 5 of IC6.

RF signal

Check from pins 50 and 53 of IC2 to pins 24 and 28 of
CNP1.

No

AUDIO signal

Check from pins 3 and 4 of CNP5 via pins 1, 2 and 6 of IC5 to
pins 29 and 33 of IC2.
Check from pins 1, 3 and 4 of CNP7 to pins 2 and 3 of IC6.

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Check as stated in item "disc Loading is not normal".

No

Is disc loading normal?

Yes

No

Check as stated in item "Playback state cannot be set".

Is playback state set when the MD PLAY/PAUSE button is
pressed?

Is audio output normal?

Check as stated in item "Audio playback circuit".

No

Is record and playback operations normal?

Yes

Check as stated in item "Record and playback operations".

No

Yes

If the objective lens of optical pickup is contaminated, MD may fail to operate.  At first, clean the objective lens to check playback
operation.  If MD fails persistently to operate, perform checks as follows.
If dust or foreign substance is accumulated on the pickup lens, playback is disturbed and indication of TOC (content of tracks) may
be disabled.  Before adjusting check that the lens is clean.  If the lens is contaminated, treat it as follows.

Turn off power supply, impregnate the lens cleaning paper with a small quantity of isopropyl alcohol, and gently  wipe the lens with
it with due care so that the lens is not damaged.  At this time do not touch the lens directly with your finger.

Is it impossible to set both high reflection disc and low
reflection disc to playback state?

No

Check as stated in item "TEST mode check".

Yes

Only the high reflection disc cannot be played back.

Yes

Is 1.3V to 1.6V applied to the pin 93 of IC1401 with the high
reflection disc inserted?

Only the low reflection disc cannot be played back.

Is 1.6V to 1.9V (record enabled) or 2.0V to 2.3V (record disabled)
applied to the pin 93 of IC1401with the low reflection disc inserted?

No

Yes

Yes

After re adjustment check as stated in item "Normal playback".

Check SW1931 loading motor PWB, and CN1931.

No

Yes

No

Yes

No

Is audio output waveform observed on the pins 26 and 28 of
CN1501?

Check connection between IC1701 and CN1501.

No

Check the main PWB.

Yes

When sound is not output although the playback time display advances during playback in the normal mode.

Is audio output waveform observed on the pins 24 and 26 of
IC1701?

Check the pins 70, 71, 72 and 74 of IC1201, and the pins
12, 16, 17, and 19 of IC1701.

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Is disc loaded when it is inserted?

No

Yes

No

Check IC1401.

No

Check CN1401,CN1931 and SW1932.

Yes

No

Check CN1401,CN1931 and IC1601.

Yes

Check M903

No

Yes

No

Yes

Is change observed on the pin 19 or 20 of IC1601?

Is change observed on the pin 12 or 13 of IC1601?

Is ejection performed when the MD taking-out button is
pressed?

Yes

Disc retracts soon after completion of disc ejection.

Yes

Check SW1932.

Is the pin 5 of CN1401 set to H state?

Yes

No

Check the Main PWB and CN1501.

No

Check the power PWB, Main PWB, and
CN1501.

Is pulse input in the pin 6 of CN1501 when reset power supply
is turned on?

Is +5V to +6V applied to the pins 17 and 18 of CN1501?

Yes

No

Check IC1201.

No

Check the periphery of Q1804 and
IC1401.

Is pulse of 8.4672MHz applied to the pin 15 of IC1401?

Is +3.2V applied to the pin 62 of IC1401?

Yes

No

Check IC1401.

Is pulse output from the pin 34 of IC1401?

Yes

Yes