AOC L42W781HS Service Manual page 27

42‟‟ LCD TV
5.4.No sound
Check the source
OK
Check signal filter circuit
Check Earphone jack
OK
U601
U603
Check speaker
OK
NG
Reset source
NG
Replace the filter or inductance
NG
Replace the Earphone jack
Analog TV signal
Digital TV signal
Scart,AV,Component,PC
signal
OK
HDMI
NG
Replace U601
NG
Replace U603
NG
Replace Speaker
Check TV system setup
OK
Check TU1
OK
Check U1
Check TV system setup
OK
Check TU1
OK
Power supply U4
OK
Check U21
Check U9,
OK
Check U101
NG
Check U501
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AOC L42W781HS
NG
Replace TU1
NG
Replace U1
NG
Replace TU1
NG
Replace TU4
OK
Check U6,U7
OK
OK
Check U12,U17
NG
Replace U101
Replace U501