Sharp LC-37AD5E Service Manual page 43

No sound from an external input device connected to EXT1
(SCART1).
<EXT1>
Is IN1-L audio signal sent from pin (6) of SCART1 terminal
(J1101) to pin (14) of IC3002 (VCT)?
Is IN1-R audio signal sent from pin (2) of SCART1 terminal
(J1101) to pin (13) of IC3002 (VCT)?
Refer to "No sound output in all modes".
No sound from an external input device connected to EXT2
(SCART2).
<EXT2>
Is IN2-L audio signal sent from pin (27) of SCART2 terminal
(J1101) to pin (12) of IC3002 (VCT)?
Is IN2-R audio signal sent from pin (23) of SCART2 terminal
(J1101) to pin (11) of IC3002 (VCT)?
Refer to "No sound output in all modes".
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 (VCT)?
Is IN3-R audio signal sent from pin (5) of J1201 terminal to pin
(15) of IC3002 (VCT)?
Refer to "No sound output in all modes".
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
(SW)?
Is D-SUB-R audio signal sent from J2702 to pin (2) of IC2704
(SW)?
Is D-SUB-L audio signal sent to pin (10) of IC3002?
Is D-SUB-R audio signal sent to pin (9) of IC3002?
Refer to "No sound output in all modes".
No sound from external input devices (1)
YES
No sound from external input devices (2)
YES
No sound from external input devices (3)
YES
No sound from external input devices (4)
YES
YES
Check pins (6) and (2) of SCART1 and connection to an external
NO
input device.
Check pins (27) and (23) of SCART2 and connection to an exter-
NO
nal input device.
Check pins (3) and (5) of EXT3 (J1201) and connection to an
NO
external input device.
Check the line between J2702 and IC2704.
NO
(Q2703, Q2706, etc.)
NO Check the line between IC2704 and IC3002.
4 – 3
LC-37AD5E