Hi, welcome to Just answer
Please tell me its complete model number
and are you using HDMI or component cables ?
We are using HD7 I
Sorry that should be HDMI
Thanks...from what you have described it sounds like a power supply issue. The power supply on these models include the high voltage inverter which supply voltage to back-light ... if you are willing to do this yourself then leave the unit unplugged and take the back off the TV...then check the board where power cord plugs in
If you get a tech. involved then the cost of repair/replacement will be around £120-£150 including parts
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