Sony KDL-43W780C Service Manual ▷ View online
TUS/TUS-A BOARD
125
IC2601
DDEM1.2V
DDEM1.1V
DDEM3.3V
Tuner
126
DMD_RESET1
IC2601
Tuner
TUS/TUS-A BOARD
127
IC2201
1
Tuner
TUS/TUS-A BOARD
128
Troubleshooting
3-4-10
. NO PICTURE: @ Tuner COL-T2 / BRZ / ARG
No Picture
Noisy Picture
Which is NG?
Analog RF or Digital RF
Both
Sound is normal ?
Check IC9001(Brownie)/
IC9001(Ayu2)
Yes
Confirm ANT connection
Digital only
Connect ANT Cable
correctly
Confirm Power supply
for RF input circuit
A2.5V / LNA_5V
Confirm RF Level and AGC
of Analog R F by Service m ode
Analog only
OK
No sound
Check RF input circuit
Include
TUS: IC2501 Pin6
TUS-A: IC2602 Pin4
Check IC9001
(Brownie)
Confirm tuner c ontrol line
TU_SCL / TU_SDA
A_RESET
Confirm IF1 line
IFOUTP1 / IFOUTN1
NG
OK
OK
OK
Check Power supply
circuit
Check M’t condition
in tuner c ontrol line
Check M’t condition
in IF1 line
NG
NG
NG
AGC = 0
Confirm Power supply
for Digital Demod
DDEM1.1V / DDEM3.3V
Confirm Demod c ontrol line
I2CB_SCL / I2CB_SDA
DMD_RESET / OSC_ENBN-1
OK
OK
Check Power supply
circuit
Check M’t condition
in Demod c ontrol l ine
Check M’t condition
in AGC2/IF2 line
NG
Check IC2201
NG
Error free
Confirm BER of digital RF
By Service mode
Check Brownie and
M’t condition in TS line
Confirm RF Level and AGC
of Digital RF by Service mode
NG
RF Level=High
AGC=Low
RF Level =Low
AGC=High
AGC=Low
AGC=High,
Which is NG?
Terrestrial or Cable
Both
Check IC
TUS: IC2501
TUS-A: IC2602
Either
L
Confirm AGC1
(TUS: IC2501 Pin6)
(TUS-A: IC2602 Pin4)
Check M’t condition
in AGC1 line
Input signal is too big
Set LNA off
H
Note:
(AYU2) – IC9000
(Brownie)- IC9001
Tuner
3-4-9