Power will not stay on...

I had this problem with mine about 4-5 years ago. i was watching it one night and snap/pop it went off. i tried to turn it on and it would click on and go right off. i took the dang thing in to repair shop and it cost me $450.00 to fix the overheated circuit board, according to the repairman, he stated that this is a problem with this tv. so here we are again with the same problem 4-5 years later. in my opinion this is one of pioneers biggest piece of junk electronics ever made. when a $2000.00 plus tv lasts less than ten years there is a problem. i hope this may kinda help answer someones questions. good luck tim

If the power lamp is blinking a 5 times and repeating, then you probably have a Defective Lamp Driver Power Supply (Ballast). With this many users experiencing the same problem, it would seem that Sony, being a responsible manufacturer would issue a recall, or find some way to make it right.

The Samsung rear projector TV's have a Fail Safe circuit connected to the Flyback transformer, if the power at RR402S dosn't reach 2.25 v in a few seconds the Micom kills power to the switching IC. Most of the time this problem originates in the power section. It could mean the Flyback Transformer is getting bad. But most of the time I have found that the Switching IC is failing. This IC is located between Transformer T801S and attached to large Aluminum Heat Sink. It is identified as IC831S (STR-X6456).

You probably have a short in the horizontal deflection scan derived power supplies. This would require some pretty good trouble shooting tecnics and most importantly a schematic to check out these circuits.Maybe a diode? Maybe a vertical IC ? When the power supply has an overload it will try to start maybe three times and then shut down depending on the particular make and model of your tv. Your HV spltter block could be shorted also.

I'd like to know if you figured out what the problem was too. Mine is going through power off/power on cycles at seemingly random instances as well. I can't reproduce it on purpose. Temperature or time running doesn't seem to matter. I've tried different inputs, and the problem still happens randomly. I called InFocus, and they said it MIGHT need the lamp replaced, but it was unlikely the cause of this problem. A local tech shop said it might simply be a loose internal wiring connection. They couldn't help unless they actually witnessed the problem, which I can force to happen. So if you had a solution or service guy fix it, I'd love to know what happened.

We had the same problem.  Call it a big coincidence but we opened the panel around the inputs in the back after unplugging the various connections and completely vacuumed it it out with small computer vacuum attachments, as it was very dusty.  Left it unplugged for a day.  Turned it on with nothing attached and it stayed on the first time.  We moved it back in place and it is working fine....for now.   We were told it would be $400 to fix.  Being four years old we would probably just buy something else rather than taking a chance of having to fix it again in the future. Good luck.

My Mom had the same problem called for a service call but he couldn't find the problem so she bought a new TV. I brought this one home, about an hour trip, in a trailer plugged it in and it worked. I guess the bouncing around did something. Go figure

I had mine repaired for same problem. Soon after it was doing same thing and repairman looked at it again. Problem was and is leaking capacitors. My unit is working now (some issues with brightness - need a remote). I won't put any more money into it. Already spent over 300. John

A good guess is that the high voltage sweep circuits are developing a problem that needs a very good technician (not a handyman). There are voltages as high as 32,000 volts being developed. If anything goes wrong that might cause this voltage to go higher - there is circuitry that detects this condition and shuts down the power supply. This is to prevent unsafe X-rays that may be generated. It will reset and kick out every time you turn the set on (unless you fix the problem).

Its possibly the lamp ...check the lamp light which is on the right side of the tv where the green power light.....if you turn the power on abd the lamp light goes orange ...you may have to replace the lamp if it goies red and flashes it could be the lamp or something near the lamp inside the tv ....check the tv manual ...it describes the lamp button

My Television is doing the same thing, the set was on and it went off as though we turned it off. Now when we push the on button it tries 3 seperate times to come on, but never does. We can hear what sounds like tubes warming up as always when turning it on, but it shuts down before the screen comes on. Is it cheaper to just buy another set than trying to get one of these repaired?

I had a similar problem with my TV and didn't want to spend the money to fix it. Disconnect the convergence board (bottom left of backside). Turn the TV on and run it without convergence for about 20 min. Unplug the TV to reconnect the convergence board. Turn the TV back ON. The only problem is, you have to leave your TV ON all the time. Instead of shutting the TV off just switch to an unused Video channel. People leave computer monitors running all the time.

Samsung does'nt make the original replacement lamp so after replacing with new model lamp T.V. would shut down intermittently.I thought it was a defective lamp so I replaced it again. same problem.After talking to various tech men I decided to take a look. Fan worked properly but I noticed a flaw in the rear lamp cover. I by passed the switch with the cover off and the T. V worked perfectly. My theory is the new lamp operated at a little higher temperature and the cover restricted the air passing over the lamp from the cooling fan from exausting out the rear of the set.A slight modification on the rear cover cured the problem.

I also have the same problem and the repair guy wants $575 to fix it. he said the main power supply board has to be replaced. I'd do it myself but haven't found the board online anywhere yet.