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– 89 –

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.

– 90 –

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.

– 91 –

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

– 92 –

Yes

Is initialization performed normally when high reflection disc is
played back?

Does disc rotate normally?

No

No

Check IC1201.

Is lead-in switch turned on in the TEST mode when the pickup is on
the innermost periphery?  (Is the pin 63  of IC1401 on L level?)

No

No

Check SW1936, soldered joints of mechanism switch PWB, and
periphery of pin 6 of CN1932.

Yes

When it has been confirmed that EEPROM value is normal in the TEST mode

Does the playback time display advance?

Check the position as stated in item "Lead-in switch position
measurement mode".

Insert the low reflection disc, and after verifying the audio output in the normal mode playback set the record/playback TEST mode.

Is recording performed after displaying TEST REC?.

Yes

No

Check whether the disc is record-prohibited.

Is RF waveform output to the pin 1 of IC1201 or TP1201
when playback is performed after recording?

No

Does RF pattern appear on the pin 50 of IC1201 during
recoading?

Yes

No

No

Check for IC1201 soldering failure.

Yes

Is output waveform given to the pins 22 and 24 of CN1501 in
AUX input record in the Normal mode?

Is input waveform given to the pins 3 and 5 of IC1701?

Yes

No

Check the main PWB.

No

Check connection between IC1701 and CN1501.

Check the periphery of IC1701, and the pins 70, 71, 72, and
73 of IC1201.

Yes

Yes

Does the level of pins 3,26 and 39 of IC1401 in record state
differ from that in playback state?

Check IC1300 to 1302 and periphery of CN1300.

Check periphery of IC1401.