Sony BRAVIA KDL-55W900A, Service Manual, Page: 35 / 241

RB1G
CHASSIS
W900A/904A/905A
Troubleshooting
3-2. LED Blinking
3-2-1. LED BLINKING 3x (DC Alert, Audio Error & Communication Error)
(*)
Size B* Board Type G* Board
Type
OTHERS JP
3-time blinking
Ch k D 1 0V t
DC_ALERT
NG
DMD_TU_I2C
or
I2CB bus check:
I2C bus dumping or
TUNER
NG
40” BA2-S BA2-W G1A
46” BA2-S BA2-W G1A
55” BA2-S BA2-W G1B
Check D+1.0V at
JL9129
on the B* Board
F9105,IC9103,etc
(B* Board)
Speaker
Check
Speaker Impedance
at SP Connector
NG
OK
AUDIO
NG
I2CB bus check:
Probe CL2205,
CL2206
I2C bus dumping or
AYU2
Brownie
OK
Check +3.3V_MAIN_1
at JL9116 on
the B* Board
F9102,IC9102,etc
(B* Board) Check AUDIO+12.5V
at pin 8/10 of
G* Board
NG
NG
OK
SPIC check
Probe RB8522
SPI dumping
resistor
or AYU2
CN9101 on
the B* Board
G Board
Check +12 5V
OK
OK
OK
I2C_CCP check
R8502 and
R8503
I2C_CCP Pull
U
Check +1.8V_MAIN on
IC9201,etc
NG
Check +12.5V
at Power Amp side
of F4601
on
the B* Board
F4601,IC4601,etc
(B* Board)
NG
OK
(Continue) #2
HDMI
R8503
OK
Up
Pin 2 of IC9201
,
(B* Board)
OK
IC4601,etc
(B* Board)
OK
(Continue) #3
I2CA bus check:
Probe CL5023,
CL5024
I2CA bus
dumping
resistor
or AYU2
NG
OK
NG
Check +5V_MAIN
at JL9132 on
the B* Board
IC9101,etc
(B* Board)
35
OK