Sharp LC-37XD1RU Service Manual page 8

LC-37XD1E/RU SUPPLEMENT
No audio output from the
headphones.
Is there audio output on pins
(2) and (3) of the headphone
terminal (J1301)?
NO
Is audio input/output signal of
pins (3) and (5)/(1) and (7) of
IC303 (OP-AMP) normal?
NO
Is audio output signal (SPK-
OUT L/R) properly sent from
pins (28) and (27) of IC3701
(MSP)?
NO
Check audio input signal of pin
(67) of IC3701(MSP), pins
(39) and (12) of the power
line5 and 8V, pins (3) and (2)
of I2C-LINE, and peripheral
circuits.
No sound except from speakers (3) -1
No audio output from
EXT1 (SCART) terminal.
Checklist:
1) Is the MUTE button on the remote control set to ON? ... Set to OFF.
2) Check the connection to external devices....Is there any improper connection?
3) ls S-MUTE-LINE [IC1710 (pin 92)] at H?....It is defective. Check the IC1710.
Is audio signal sent to pins
(3) and (1) of EXT1
(J1101)?
YES
Check the connection to
EXT1 (J1101) and exter-
nal devices.
NO ls S-MUTE-LINE
[IC1710 (pin 92)] at H?
(Check Q1106/Q1105
operation.)
NO
Is audio signal sent
from pins (33) and (34)
of IC3701?
YES
Check the audio signal
output line from pins
(33) and (34) of IC3701
to pins (3) and (1) of
EXT1.
2 – 2
NO Check the power supply
8/5 V pins (39) and (12)
of IC3701 and periph-
eral circuits.