CD-MD3000 (serv.man7). Trouble shooting guide - Sharp Audio Service Manual (repair manual). Page 3

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CD-MD3000H/CD-MD3000W
– 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
When MD fails to operate
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.
MD SECTION
• Playback state cannot be set.
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
• Audio playback circuit
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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