Hi,
You have to check the back light inverter of your lcd tv. In all lcd tvs there are back lights to illuminate the pixels. There are two types of back lighting in use . CCFL ( cold cathode fluorescent lamp) and LED (light emitting diode). In you your tv it will be CCFL. If it is CCFL then it need an inverter (voltage step up circuit) for getting its working voltages. Normally it will produce above 1000V in low current. In the inverter circuit there will be inverter transformers. If the winding of the transformer get shorted then the inverter will drain a high current from the power supply. If so then the current sensing circuit senses the same and it will shut down the power supply. That's why it do the cycle ON an OFF repeatedly.
Just check the inverter board. Normally there will be three circuit boards in LCD TV. Mother board, SMPS (switch mode power supply) and inverter board. In some tvs the SMPS and inverter bord will com-pained as one board. you have to check the inverter transformers. there will be 4 or 6 inverter transformers. if available replace the inverter board as a whole.
Also check the electrolytic capacitors in the power supply. if any of the capacitor seems like one that in the picture, then replace the same and then only go for the inverter board
ok
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