http://www.samsung.com/us/support/detail/supportPrdDetail.do?menu=SP01&prd_mdl_name=LN-T4665F
http://www.retrevo.com/support/Samsung-LN-T4665F-TVs-manual/id/1235ci960/t/2/
http://www.scribd.com/doc/26351010/Samsung-Lcd-Lb350-650-Training-Book
www.plasma-television-repair.com/Sample-Preview-Plasma-Tv-Repair-Training-Manual.pdf -
www.scribd.com/doc/.../LG-TV-Plasma-Training-Manual -
http://www.scribd.com/doc/13862078/SONY-KDL42XBR950-TV-Plasma-Training-Manual
I have given you LCD and Plasma, manuals.... As you have asked for two differing sorts of sets, ???
please find above service and training manuals to help you get a handle on your problem, I am glad to see you started at least in the right place, the Power supply, well done! Please use the troubleshooting procedures and i think you will soon be able to repair your set, usually all one can do is be a "Board Jockey", but you may have to go Down, to component level to effect repair, so be safe good luck.
Troubleshooting say if it is shutting down, after a certain amount of time, of working and then faulting, then it is most definitely a "Thermal" problem, the way we "Find" problems such as this is "Freeze Spray" you use this on each component that is suspected of being the "Culprit" and you will soon,find that errant component. Now also not every fault is a Capacitor, I see many, many people that think, that Capacitors are always the "Culprit" now while that may be true in a few cases, a faulty Electrolytic Cap, or ordinary, Cap goes faulty, this is only a SYMPTOM, something has damaged those caps causing them to "Fail". One MUST always find the root "Cause", otherwise if you just treat, the SYMPTOM, the "Cause" will just make the "Symptom" come back, in short order, as the prime cause still, hasn't been fixed., Now Capacitors hate AC ripple, or Over Voltage. Thats it. Oh.. and Heat, if these Capacitors, are too close to a Heat Source, then thats a prime cause of failure. Resistors, hardly ever go faulty,and if they do, it is generally obvious. However it doesn't hurt to check values with our Multimeter. Remember though resistors are made, with up to 20% tolerance from stated value, as such, are not too critical, unless in Timing circuits etc. Always check, the Values, of resistors, as with any other component, with the power OFF. Now Diodes especially "Zener Diode", are another thing to check, those and ordinary "Signal Diode" should always be suspect. next we have Transistors and IC's. The Transistors MUST ALL be checked to see if they have a good, "Junction" this is done, with our meter set to "Diode Test" and usually are about 0.6 to 0.7. With IC's you must check, voltage levels, or Logic Levels, going in and out, have a look at the circuit diagram, and it will tell you what they should be. It is a good idea to always measure the Power Supply voltages, see if a "Rail" is Low, that will be because some component has gone somewhat or all short circuit, to Earth, now, if the "Rail" is Higher, suspect an "Open Circuit" component, like a Diode, or Transistor. The voltages expressed in the manual are spot on, ANY variation MUST be investigated. I have been doing all this for over 30 years now, and I do indeed wish, we could have a set of "Symptoms" and be ables to say.. "Oh that;s the so-in-so and replace this" however unfortunately this although does happen, most "Symptoms" can have literally tens, of "Causes" all often "Interlinked" One simply has to do a methodical troubleshooting procedure, and always think, "are my Voltages Correct" as this is how, you Fix the problem, by making them so. Keep up the good work. If that link above doesn't furnish a Service manual, it is imperative you get one, even if you must pay for it. It will pay for itself in about 2 mins. Now just replacing boards will most likely just end up with more faulty, boards, as related you MUST ensure that you have the cause of the event, before we change anything. I have seen so called, "Techs" replace every board, and virtually every component, and that STILL didn't fix it, because the "Fault, or Cause" lay elsewhere, and had not be repaired FIRST, you see that FIRST STEP, like everything in life, is, CRITICAL.
