I had a similar problem with my 42 in Philips LCD HDTV.
Here was the problem. My Power Supply Board had several bad capacitors. I opened my TV (warranty was expired of course) and found four bulged capacitors on the PSB. Many major electronics companies Philips/Magnavox, Sony, Panasonic, and others were sold capacitors that failed in 2-5 years instead of 10-20. The capacitors fail prematurely due to a lack of preservatives. Unfortunately, they were installed in all sorts of devices and cause a wide range of failure problems.
Here are some options for you.
1. Have it fixed by a professional $$$$$$$??????? (Is it under warranty?)
Remember, TVs CONTAIN HIGH VOLTAGE AND CAN KILL YOU! Do this at your own risk.
2. Open your TV and find PSB. (The board that the power cord plugs into) Check for faulty caps. If you find some (bulged or leaking) bad caps replace the entire board. The entire board costs around $250 right now because they are in high demand right now. They can be found online. I would definitely shop around though.
3. Remove and then replace individual faulty caps. This takes some soldering skill.
Caps are inexpensive and if you can take care of it yourself it will save you hundreds.
This may be your problem. If you determine that it might be.
I have a Tip/How TO tutorial on this site that may also help. It gives step by step instructions for replacing caps on PSB #715t2432-2. If this is your board you are in luck. Here is the Link: Fixing the Philips Turns/shuts off on its own problem. I'm working on uploading pictures to help guide people though the process as well. Let me know if I can do anything to help.
Hope this helps and if it does please rate it accordingly. Good luck.
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