Hi Shaun,
I take it that this is a CCFL backlit TV? Sounds like it's giving a Code 1 error message, 3 seconds between each blink, which is an invertor SOS. So it could be lamp short circuit protection, lamp open protection or arc protection, in short, a buggered CCFL, or it could be a fault on the psu, like dry joints or mismatched resistance on the inv. drive transformers. Something to be getting on with, anyway. Can upload service manual should you need it.
Bruce