There is one thing you could check under setup or however the set up pages on your TV work? But before giving up to what could be an internal fault i would take a look at this first. Most of the flatscreen Televisions now have a sleep mode where by you can set the television to switch off into standby mode. Make sure this timer setting is not adjusted to 15 secs. If unsure try and find the part where by you take the unit back to factory settings if that exists. Otherwise you have an internal fault and will need a repair. Hope this helps
carlito Corway
November 2010