3 Blinks/4 Blinks Error Code
3 Blinks Error Code
Since the IC (IC9805) that generates the monitored 3.3V for 3 blinks condition and the IC (IC9003) that detects this condition are both located on the A board, then the A board is the only suspect when the TV shuts down and the power LED blinks 3 times.
Replace the A board.
4 Blinks Error Code
Primarily the P board causes 4 blinks, followed by the A board.
To troubleshoot a 4 blinks condition, measure the voltage at pin 12 of connector P25. If the voltage goes high, the P board is the problem. If the voltage stays low, then the A board is the problem.
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