Sharp DV-500D Technical Manual page 92

Focus is not pointed.
No
Does pickup move up
and down?
Yes
Yes
Is FE signal measured
from IC303 (pin 27)?
No
Is signal measured
Yes
from IC303 (pins 57,
58, 59 and 60)?
No
Is any signal measured
Yes
from IC301 (pins 17 and
18)?
No
Replace pickup.
Laser is not turned off.
Yes
Is "H" measured at IC303 (pin 51)?
Yes
Is 3.3V measured at the emitter of Q301.
Is 3.3V measured at the collector of Q303.
Yes
Is 3.3V measured at the AB connector (pin 11)?
Yes
Check AB connector, and replace pickup.
Neither image nor voice is output.
Insert disk.
Yes
Is disk clamped?
Yes
Is RF signal measured at IC303 (pin 34)?
Is it corrected when main board is replaced?
Yes
Check IC6001, IC6002 and IC6003.
No
Is FE signal output
from IC707 (pin 38)?
Yes
No
Is FE signal output
from IC707 (pin 43)?
Yes
No
Is FE signal output
from IC707 (pin 43)?
Yes
No
Is focus drive signal
measured from IC702
(pins 17 and 18)?
Yes
Is drive signal measured
at the connector AB (pins
2 and 4)?
No
Yes
Check connector unit or
replace pickup.
No
No
No
No
No
No
No
Check the line between IC303
(pin 27) and IC707 (pin 38).
Check the line between IC303
(pin 27) and IC707 (pin 38).
Replace IC707.
Is 8V measured at IC702
(pin 21)?
Yes
Replace IC702.
Check between IC702 (pins
17 and 18) and connector AB.
Replace IC303 or IC707.
Check 3.3V line.
Is "L" level measured at the collectors of Q303 and Q304?
Check between Q303 and AB connector.
Check loading SW.
Clean objective lens.
Replace pickup.
11-4
No
Check 8V line.
DV-560H