Sharp LC-26SA1E/RU Service Manual page 38

LC-26SA1E/RU, LC-32SA1E/RU
No sound from external input devices (2)
No sound from an external input device connected to EXT3.
<EXT3>
Is IN3-L audio signal sent from pin (3) of J1201 terminal to pin
(16) of IC3002?
Is IN3-R audio signal sent from pin (5) of J1201 terminal to pin
(15) of IC3002?
Is the audio signal properly sent from pins (28) and (27) of
IC3002?
Is the audio signal of pins (1) and (7) of IC303 (OP-AMP) sent
properly?
Is the audio output signal of pins (13) and (16) of IC302/IC301
(MAIN-AMP) normal?
Check CONNECTOR (P301) and Speaker (right and left).
No sound from external input devices (2)
No sound from EXT4 (AUDIO) connecting an external input
device.
<EXT4>
Is D-SUB-L audio signal sent from J2702 to pin (15) of IC2704?
Is D-SUB-R audio signal sent from J2702 to pin (2) of IC2704?
Is D-SUB-L audio signal sent to pin (10) of IC3002?
Is D-SUB-R audio signal sent to pin (9) of IC3002?
Is the audio signal properly sent from pins (28) and (27) of
IC3002?
Is the audio signal of pins (1) and (7) of IC303 (OP-AMP) sent
properly?
Is the audio output signal of pins (13) and (16) of IC302/IC301
(MAIN-AMP) normal?
Check CONNECTOR (P301) and Speaker (right and left).
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO Check pins (3) (J1201) and (5) (J1201) of EXT3 and connection
to an external input device.
NO Check IC3002 or peripheral circuits.
NO Check IC303 or peripheral circuits.
NO Check IC302/IC301 (MAIN-AMP), HEADPHONE and peripheral
circuits.
NO Check IC3002 or peripheral circuits.
NO Check IC303 or peripheral circuits.
NO Check IC302/IC301 (MAIN-AMP), HEADPHONE and peripheral
circuits.
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