QT-CD180 (serv.man5). Part 3 - Waveforms, Troubleshooting tables, IC tables - Sharp Audio Service Manual (repair manual). Page 5

– 23 –

Does the sled motor run in FF/REW state when the CD
TEST MODE is set ?

Is the following wave output to the pin 67 (TRO) of IC802
during track search in normal playback ?

Is the following wave output to the pins 12 (TEO) of IC801
during track search in normal playback ?

Yes

Yes

No

Check as stated in item "SLED MOTOR OPERATION FAILURE".

No

IC802 failure.

No

Check the PWB pattern between pin 67 (TRO) of IC802 and pin
25 of IC803.
Check the PWB pattern between pins 26 and 27 of IC803 and
Optical pickup.
If OK.  Optical pickup failure.

Yes

Is the above wave output to the pins 64 (TEI) and 65 (TEZI)
of IC802 during track search in normal playback ?

No

Check the PWB pattern between pin 12 (TEO) of IC801 and pins 64
(TEI) and 65 (TEZI) of IC802.  If OK. IC801 failure.

Normal.

Yes

Is the following wave output to the pin 60 (RFZI) and 61
(RFRP) of IC802 during track search in normal playback ?

No

Check the PWB pattern between pin 22 (RFO) and 18 (RFIS), 17
(RFRP) of IC801 and pins 60 and 61 of IC802.  If OK. IC801 failure.

Yes

TRO

TEO

TEI

TEZI

RFRF

REZI

Is above wave obtained between pins 5 and 6 of IC803 ?

Is following wave output to the pin 72 (DMO) of IC802 when
the Function is changed to "PLAY" from "STOP" ?

No

Yes

Check the procedure in "HF ERROR".
If OK.  IC802 is faulty.

Check the PWB pattern between pin 72 (DMO) of IC802 and pins
5 and 6 of IC803.  If OK.  IC803 is faulty.

No

Is above wave obtained between pins 5 and 6 of BI803/
CNS803 ?

Yes

Check the PWB pattern between BI803/CNS803 and IC803.

No

BI803/CNS803 connection failure or optical pickup failure.

Yes

DMO