Sharp lc-42ad5e Service Manual page 43

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?
Is audio signal sent to pins (3) (L-ch) and (1) (R-ch) of EXT1
(J1101)?
Is S-MUTE-LINE [IC1710 (100)] at H?
Is audio signal sent from pins (24) (L-ch) and (23) (R-ch) of
IC3002?
Check the audio signal output line from pins (24) (L-ch) and (23)
(R-ch) of IC3002 to pins (3) (L-ch) and (1) (R-ch) of EXT1.
(Q1108, Q1107, etc.)
No audio output from EXT2 (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?
Is audio signal sent to pins (24) (L-ch) and (22) (R-ch) of EXT2
(J1101)?
Is S-MUTE-LINE [IC1710 (100)] or S2-MUTE-LINE [IC3003 (25)]
at H?
Is audio signal sent from pins (22) (L-ch) and (21) (R-ch) of
IC3002?
Check the audio signal output line from pins (22) (L-ch) and (21)
(R-ch) of IC3002 to pins (24) (L-ch) and (22) (R-ch) of EXT2.
(Q1104, Q1103, etc.)
No sound except from speakers (1)
NO
NO
YES
No sound except from speakers (2)
NO
NO
YES
YES Check the connection to EXT1 (J1101) and external devices.
YES Check IC1710 and its peripheral circuit, and S-MUTE line.
(Q1105, Q1106, etc.)
NO Check IC3002 or peripheral circuits.
YES Check the connection to EXT2 (J1101) and external devices.
YES Check IC1710/IC3003 and its peripheral circuit.
(S-MUTE_LINE, S2-MUTE_LINE, Q1101, Q1102, D309, D310,
etc.)
NO Check IC3002 or peripheral circuits.
4 – 5
LC-42AD5E/RU/S