Sony XR-55A75L Service Manual page 55

TROUBLESHOOTING
2.0 LED Blinking: 2x (Main power Error)
2-time blinking
Check "12.7V_MAIN"
Yes
at pin 5,6,7,8 of CN1700
G-Board
on B-Board,
Voltage > 13.2V ?
No
B-Board
55
SYS SET