The TV does not start because it is in protect mode, this happens when a problem is detected, as a fault or an incorrect voltage.
Try first leaving the TV power cord unplugged for some times, let say one hour or so.This will drain power, discharging capacitors and resetting the unit.
Ensure that the fault is not coming from a faulty receiver box sendingbad signal, check if you get same problem on dvd with no receiver boxconnected.
If that does not work, and you keep having the led in front of the TV on, and tv not turning on,that indicates a fault condition.
The light indicates a diagnostic state called protection.
When the unit goes on protection there are only two possible causes.
1Theinternal circuits are jammed because of electrostaticcharges accumulating on capacitors, or because of a wrong voltage had been detected. This started theprotection circuit.
2 The protection circuit detected a wrongvoltage or abroken contact, identified an internal fault and kicked in, starting the fault mode.
If you are in situation one, then theTV will reset just unplugging power cord for one or two hours,sometimes even minutes.
If you are in situation 2 , then there is an internal fault.
Common faultsthat can occurr are a blown capacitor on power board, aconvergence IC has blown, or a fault on Digital board.
Check alsothe video cable or any external connection cable, if the cable is shorting, or the connector is bad, youcan get same flashing statebecause of the video cable.
Try moving the video cable, and if the cable is not built in, then also try a replacement cable.
If under warranty contact the manufacturer ringing the number on the user manual
If you want to repair at your own expenses, just locate any good qualified repairer.
You can find parts here.