Led Blinks 3 Times - Panasonic TH-42PX75U Technical Manual

LED blinks 3 times

<Trouble Mode and Defective Board>
Warning: Disconnect AC Power prior to
Trouble Mode Defective Board
making any disconnection or
connection.
3.3V down SOS D Board
<How to find the defective boards>
The D board is defective.
Note: CN = Connector
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