I purchase my TV 02/01/2009. My TV loses picture. During that period, the screen is white. This problem happens at will,and can last up to 30 to 45 minutes, before picture returns.

Try going into set up menu and look for a screen degauzing function or try setting the screen temp. to warmer or cooler.

change your device cables or try to put at a pc to check if isworking your pc

Hi,
KP-51HW40 shuts off due to incorrect white balance and blue arch lines is an evidence of that incorrect white balance. I hope tv standby red light would flashing 5 times then 3 seconds pause and again 5 times when tv shuts down.
This is rear projection tv that has three picture tubes (red-green-blue) inside to generate picture that projected at front screen. These three picture tubes must be drive with correct drive voltage to produce good picture of each color.
Solution for your tv problem is Screen Voltage adjustment that can be done easily if you are handy with electronics stuff repair.
Let me know your expertise level to guide you more and if you feel unconformable by tv repair then local tv repairman will help you to adjust white balance in tv.
Hope these info will help you.
Let me know if you have additional questions.
Thanks.

I would try the lamp first,if it has never been replaced they only last for up to 5,000-8,000 hours.

Ours is crapping out just like yours. Picture goes out, "black and white squiggles" appear in the top left of the screen then TV input appears, then it either repeats or gives me my picture back. This happens with both the HDMI slots (tested all 3) and both Component slots. Seems like the bulb or a circuit board on the TV is faulty. What a piece of ****, never spending another dime on LG products. I did get it to come back by hitting the back of the TV with a good slap, but it gets really annoying.

Sounds like vertical collapse. Have tech replace vertical ic. Shouldn't be to expensive

check some settings such as pbc

thank you

Hi.

Just read your list of problems The first fault (Diagonal lines & picture collapse from left & right) Sounded like either A poor connection or dry solder joint either on scan coils or scan coil plug / socket on main pcb.
If this were the case the engineer that called out should have spotted this & sorted it very easily. But you say it is still the same so what did he do ?
Did he give you a reciept with break down of what he did ? If yes please post it here for me to go over.

The sound problem you describe has thrown me a little so could you please post your tv model number on this page so I can see if this is a stock fault.

The static shocks you are getting is relatively normal & not a problem unless you are getting them off of speaker grilles or even tv casing if it is silver in colour.
I am UK based & have access to samsung technical but I will need your tv model number.

http://dysonmanuals.inc.io/

Chris.

Classic bad picture tube! End of natural life for that make/Model.

The  current sensing circuit is turning the video on/off.

The orangey look also indicates CRT no good.......T.