Y
N
Y
N
Y
N
Replace
U300
N
Y
check
Z600/Z601
replace
U600
if 3.3V/12V no voltage
or low voltage,check
relevant circuitry
Fig4.Picture OK, but No Sound
Check the
speakers
Check the power supply
voltage of U700 and mute
control circuitry if
regular
Check voltage of Pin23 of
U700 and Q700/Q701 and
relevant mute circuitry
check the pin23/24
of U600 input if
normal
Picture Good,but No Sound
increase the volume and press the
mute key on remote control
test waveform of Pin27/28/29/30 of
U700 if OK
Test waveform of
Pin6/9/10/11 of u700 if
OK
test waveform of
Pin54/Pin55 of U300 if
regular
