Sharp XL-1200 Service Manual page 31

• HF error.
Is output (tracking error signal) obtained at the pins 46 (TEI)
and 47 (TEZI) of IC802 the CD TEST MODE "STEP 4" is
changed to "STEP 5"?
Yes
test mode "step 4"
TEI
TEZI
Is output (HF signal) obtained at the pin 38 (RFI) of IC802
when the CD TEST MODE "STEP 4" is changed to "STEP 5"?
Yes
test mode "step 4"
RFI
Is output (HF signal) obtained at the pins 41 (RFZI) and 42
(RFRP) of IC802 when the CD TEST MODE "STEP 4" is
changed to "STEP 5"?
Yes
test mode "step 4"
RFZI
RFRP
Is the following wave output to the pin 55 (DMO) of IC802
when the CD TEST MODE "STEP 4" or "STEP 5"?
Yes
test mode "step 4"
DMO
Normal.
• No sound.
No sound from both L and R-ch?
Yes
Is +4.5V applied to pin 83 (DVDD) of IC802?
Yes
Is signal of pins 82 and 85 of IC802 output?
Yes
The main PWB is faulty.
No
test mode "step 5"
No
test mode "step 5"
No
test mode "step 5"
No
test mode "step 5"
No
No
No
– 31 –
Is output obtained at the pins 3 and
8 of CNP802/CNW3.
Yes
Check the periphery of IC801.
Check the PWB pattern between
pin 12 (TEO) of IC801 and pins 46
and 47 of IC802.
Is it normal ?
Yes
Check the PWB pattern between pin 49 (TRO) of IC802 and pin 19
of IC804.
Check the periphery of IC804 and CNP802/CNW3.
If OK. Optical pickup failure.
Is output obtained at the pins 4 and
5,6 of CNP802/CNW3.
Yes
Check the periphery of IC801.
Check the PWB pattern between pin 19 (RFGO) of IC801 and pins
38 (RFI) of IC802.
If OK. IC801 is faulty
Check the periphery of IC801.
Check the PWB pattern between pin17 (RFRP) of IC801 and pins
41 (RFZI) and 42 (RFRP) of IC802.
If OK. IC801 is faulty.
Check the periphery pins 28~32 of IC802.
If OK. IC802 failure.
Check the interval between the pins 82 or 85 of IC802 and the pins
2 or 5 of IC901.
Check the PWB pattern between R819 and Q861.
Check the peripheral parts of IC802. If OK, IC802 is faulty.
XL-1200/1200C
Optical pickup failure.
No
IC801 is faulty.
No
Optical pickup failure.
No