Sony XR-55X90K Service Manual page 15

TROUBLESHOOTING
1.0 No Power - PSU
No Power
Before open TV set rear cover & check details,
recommend to do force factory data reset
(method refer "factory data reset")
TV can boot up
End
No Power
Still
Check STBY 3.3V
NG
C1708 near CN1701
on BM5A board
OK
BM5A
board
NG
Replace Harness
between G* Board and
BM5A board
OK
Harness
u-Com Failure
DDCON/LDO
Main Device Failure
NG
Replace G* Board
15
SYS SET