问题在主板上，检查下DC转换电路和音频电路。 以下是维修手册复制来的：3 times blinking (Main Board Error)
3 times blinking
Check D+1.2V at
JL6002
on the B* Board
F6001,IC6001,etc
(B* Board)
Speaker
Check +3.3V_MAIN
at JL6005 on
the B* Board
Check
Speaker Impedance
at SP Connector
F6003,IC6003,etc
(B* Board)
Check AUDIO+12.5V
at pin 2/4 of
CN6001 on
the B* Board
G* Board
Check +12.5V
at F4601 on
the B* Board
F4601,IC4601,etc
(B* Board)
DC_ALERT
NG
OK
AUDIO
AUDIO
FE/BE Communication
NG
OK
NG
OK
NG
OK
NG
OK
Other B* Board’s parts
(Audio, Tuner, HDMI Eq...)
3 times blinking
Check D+1.2V at
JL6002
on the B* Board
F6001,IC6001,etc
(B* Board)
Speaker
Check +3.3V_MAIN
at JL6005 on
the B* Board
Check
Speaker Impedance
at SP Connector
F6003,IC6003,etc
(B* Board)
Check AUDIO+12.5V
at pin 2/4 of
CN6001 on
the B* Board
G* Board
Check +12.5V
at F4601 on
the B* Board
F4601,IC4601,etc
(B* Board)
DC_ALERT
NG
OK
AUDIO
AUDIO
FE/BE Communication
NG
OK
NG
OK
NG
OK
NG
OK
Other B* Board’s parts
(Audio, Tuner, HDMI Eq...)