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If you can give me the full model # of the tv, I can try to give you a bit more information about the problem.
Typically, however, any red flashing light with a pattern such as this indicates an internal fault, which is generally something that will need to be repaired (usually related to a faulty component on the power supply or one of the boards)
You would need to contact a repair tech for an on site diagnostic. If you'll let me know your zip code, I can help you locate the closest authorized repair shop (This is important if you're still under warranty, and even if past warranty to be sure you're getting the correct quality parts.