Did you call in and ask for an one time warranty extension or check if you bought from Costco or on a CC?
I have 50" LED LG TV and it started to show horizontal lines.
it is 18 months old and its model is
50LN5420-TC
Serial number is
308KCXM6A634
Software Version is
03.30.24
here is video about the problem showed on the screen http://youtu.be/XIw9aq29tYE
thank you

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