Skyworth 42E68 Instruction Manual page 79

Service Flow Chart
Check the mute circuit
if it is OK.
N
Fix the mute circuit
Done
Change the main
IC "U101"
N
Change the mainboard
Done
Check the voltage of "Mute" pin beside
the amplifier IC. It should not be 0V.
= 0V
Y
Upgrade the software
N
Done
OK
Done
Check if the Volume has set to "0"
or if the it is mute
N
Check the audio input line
& the audio input circuit.
N
> 0V
OK
-49-
Has video but no audio
OK
Done
Y
Done