XL-70 (serv.man5). Trouble shooting guide - Sharp Audio Service Manual (repair manual). Page 6

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XL-60H/70H
– 42 –
• Sled motor operation failure.
Yes
Yes
Is following sled feed signal output the pin 53 (FMO) of IC802
when FF/REW key is pressed after the CD TEST MODE
"STEP 1" is seted?
Is sled feed signal output the pins 10 and 11 of IC804?
Is sled feed voltage applied between both terminals of sled
motor?
No
Check the peripheral parts of IC804. If OK, IC804 is faulty.
No
C801 is faulty.
Check the BI803/CNS803.
No
Yes
Check the CD mechanism (periphery of sled motor).
If the sled motor does not run when DC2.0V is applied to
both terminals of sled motor, the sled motor is faulty.
• Sled servo failure.
Yes
Is following sled signal output the pin 53 (FMO) of IC802
during playback?
Normal.
No
IC802 is faulty.
• Track search failure
Does the sled motor run in FF/REW state when the SERVO
TEST MODE "STEP1" is set?
Is the following wave output to the pin 49 (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 49 (TRO) of IC802 and pin
18 of IC804.
Check the PWB pattern between pins 20 and 21 of IC804 and
Optical pickup.
If OK.  Optical pickup failure.
Yes
Is the above wave output to the pins 46 (TEI) and 47 (TEZ) of
IC802 during track serch in normal playback?
No
Check the PWB pattern between pin 12 (TEO) of IC801 and pins 46
and 47 of IC802.  If OK. IC801 failure.
Normal.
Yes
Yes
Is following sled feed signal output the pins 12 and 13 of
IC804 when FF/REW key is pressed after the CD TEST
MODE "STEP 1" is seted?
Check the PWB pattern between pin 53 of IC802 and pins 12 and
13 of IC804.
No
Is the following wave output to the pin 41 (RFZI) and 42
(RFRP) of IC802 during track search in normal playback?
No
Check the PWB pattern between pin 17 (RFO) and 18 (RFIS), 19
(RFRP) of IC801 and pins 41 and 42 of IC802.  If OK. IC801 failure.
Yes
TRO
TEO
TEI
TEZI
FF
REW
FMO
FMO
RFRP
RFZI
FF
REW
SL 
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