No Picture
N
Y
Y
Y
N
Replace
U300
Y
Y
N
check
waveform
of Z600's
Pin8 if
regular
Replace
U600
N
N
Y
Fig3. No Picutre
check Q801 and U300's
working conditions if
regular.
Test waveform of
Pin54/55 of U300 if
have regular signal
input
check waveform of
pin1/2 of U600 if
regular
replace Tuner Z600
Replace U300
AV input if have picture
check P302 if assemble
regular
check Q805 Vcc-panel
power supply and
relevant if regular
Check P803's Pin16
BL_ON if high level,
over 3V is regular.