Hi it sounds like your power supply. Unplug the TV keep on pressing the on/off button not by using the remote .this will help discharge a few capacitors.
.Remove the back covers sliding it down the power cable.
The power supply is the board which the mains lead goes to.
.Check the capacitors which have a pressed cross on the top of them, if any have a dome shape on them, they have gone and need replacing.
It’s an easy job. Most of the time up to five will have blown.
Draw where the capacitors are and which is the –negative side
Remove the Power supply. De-solder and replace the capacitors taking note of the value in uf and voltage do not mix them.
Power supply repaired. Take care not to touch the large capacitor as it could hold a charge. That can be discharged by bridging the 2x terminals with insulated pliers across the two soldered joints.
geoffrey rhodes
August 2010
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