Hi Buddy

There have been known issues and cause is the Wi-Fi.

1. Set your SSID to 8 alphanumeric characters or less.
2, Set WPA key to 10 digits or less. (If you want, try WPA2 later.)
3. Broadcast SSID.
4. reconnect your TV to the Wi-Fi and retest.

Try to update the software. If it doesn't help then try unplugging the front panel key connection
If you wish to get some details about LCD TV repair then check the below added link.
http://electro-medical.blogspot.com/