SM-SX1/SX1W
– 36 –
No
Yes
Is any 1-bit signal from Pins 27 and 33 of IC803 output
to RLY801?
Check IC808, IC809, IC811, IC812 and IC813.
No
Yes
Does RLY800 and RLY801 operate?
Check the operation of Q801 and Q802 and the wiring of
each to the microcomputer IC907.
Check the wiring from CNP303 to CNP304 and
1-bit amplifying unit.
Cont. from page 35
No
• 1-bit amplifying section check (Signal is output from CNP303 and CNP304 but it does not sound.)
Yes
Is any signal output form Pins 2, 3, 5 and 6 of ICA1?
(Fig. 33-1)
Check the waveform of the input pin, ICA1, voltage supplied
to ICA1 and ICA1 oscillating circuit.
No
Are the waveforms of QA1 to QA8 correct?
(Fig. 33-3, Fig. 33-4, Fig. 33-5)
Check ICA2, ICA3, QA1 to QA7.
Yes
No
Are the waveforms of ICA4 to ICA7 correct? (Fig. 33-6)
Check ICA4 to ICA7.
Yes
No
Are the waveforms of QA9 to QA16 correct?
(Fig. 33-7, Fig. 33-8)
Check RA53 to FA60 and QA9 to QA16.
Yes
No
Is any signal output from CNWAM6 and CNWAM7?
Check LA802 to LA808.
Check the soldering.
Yes
Check the surrounding of the relay PWB.
No
• 1-bit amplifying section check (power trouble/protector activation)
Yes
Don't the protector activate together with drop of voltage
±
22V if CNWAM4 and CNWAM3 are disconnected?
Recheck the main body section.
No
Does the oscillating circuit operate? Check Pin 9.
Replace ICA1.
Check CXA1 crystal and CA8, CA9.
Yes
Check ICA4 to ICA7, CA36 to CA39 and RA53 to RA60.
