DV-550U
11-3
FLOW CHART NO.10 FOCUS TROUBLESHOOTING(2)
Focus servo does not function.
No
Is the FE waveform at pin(38) of IC707 present?
Check lines between at pin(27) of IC303 and all
Yes
the way up thru to pin(38) of IC707.
Is the output waveform output at pin(43) of IC707?
No
Check the power circuit line of IC707.
If OK, IC707 is defective.
Yes
Is the focus drive waveform output from pin(17) or
(18) of IC702?
No
Is the supply voltage of 8V fed to pin(21) of IC-
702? If OK, IC702 is defective.
Yes
Is the output waveform applied to pin(2) or (4) of
AB connector from IC702?
No
Check lines between the AB connector and all
the way up thru to IC702.
Yes
Check the connection of optical pickup cable.
If OK, optical pickup is defective.
FLOW CHART NO.11 LASER TROUBLESHOOTING
The LASER fails light up.
No
Is "H" level applied at pin(51) of IC303?
The IC303 or IC707 is defective.
Yes
No
Is applied to the emitter of Q301?
Check PC line.
Yes
No
Is applied to the collector of Q303?
Check a "L" level at base of Q303, Q307.
Yes
Replace Q307.
No
Yes
Is 2.3V applied to the collector of Q307?
Is 2.9V applied to the base of Q307?
Yes
No
Check between base of Q307 and all the way up
thru to pin(52) of IC303.
Is 3.3V and 2.3V applied to the pins(11) and (9) of
AB connector?
No
Check between Q303 and Q307 and all the way up
thru to AB connector.
Yes
Check the AB connector.
If OK, optical pickup is defective.
Tray is not opened.
Does it vary at IC504 (pin 94) when the
tray open-/closing button is pressed?
Is loading motor drive voltage output
to AG connector (pins 2 and 3)?
Visually check the gear and so on of
the mechanical section.
Check between IC504 (pin 94) and
tray open-/closing button.
Is loading motor drive voltage output
from IC701 (pins 9 and 7)?
Check between IC701 and IC504.
Is 8V measured at IC701 (pins 3 and 8)?
Replace IC701.
Check 8V line.
Yes
Yes
Yes
No
No
No
Is any signal input from IC504 (pins 70
and 69) to IC701 (pins 2 and 4)?
No
No
Yes
Yes
Check between IC701 and AG connector.
Summary of Contents for DV-550U
Page 5: ...DV 550U 4 1 For details on the use of each control 4 PART NAMES 14 Remote Sensor ...
Page 6: ...DV 550U 4 2 ...
Page 52: ...DV 550U ...
Page 53: ...A B C D E F G H 1 2 3 4 5 6 7 8 9 10 11 12 DV 550U DV 550U 14 1 14 2 14 BLOCK DIAGRAM ...
Page 56: ...U DV 550U 10 11 12 13 14 15 16 17 16 2 ...
Page 58: ...10 11 12 13 14 15 16 17 U DV 550U 16 4 ...
Page 83: ...Ref No Part No Description Code Ref No Part No Description Code 18 19 DV 550U ...