HiCustomer Thank you for asking your question on JustAnswer. Heat is the enemy of electronics, and these plasma sets operate hot. You might wish to unplug the TV for an hour or more. If this power reset does not allow the TV to turn on component failure is indicated. The TH-42PX50U are assembled using the wave soldering process they are known for having cold solder connections. The safety circuitry shuts the TV set down when it detects a problem. This model of TV has over 2,000 parts which include millions of transistors inside the integrated circuits. The capacitors will change value, leak and become defective. Resistors will change value and burn. Integrated circuits and transistors can go bad. This can cause other components to become defective, which can have a domino effect and cause other parts to fail. Replacing one defective part may make the TV operate for a short time but the part will fail again since if the parts that caused the failure to begin with are not replaced. The only way to know for sure what is causing the problem, which parts that are no longer within factory specs and for proper repair all the electronics must be diagnosed by someone with the correct electronic test equipment and the skills to use the test equipment. I wish I could tell you there was a quick fix or button to push that would fix the TV but that is not the case or the solution needed to get the TV operating correctly. If you wish to repair it yourself what type of electronic training do you have? What type of TV test equipment do you own? Do you own and know how to operate an oscilloscope? If you decide this is not something that you can do I expect this repair will be about $250 to $450, depending on how many parts are found to be out of factory specifications, if the problem is a bad circuit board, and if the board can be repaired or has to be replaced. A small TV repair shop will often charge less for the repair than a large electronics repair facility. Should you require further clarification, never hesitate to ask. It would be my pleasure to clarify my answer to your question. If after reviewing the above information, you have additional questions, I will be glad to answer them. My goal is your 100% satisfaction with all questions I answer. Please click the green ACCEPT icon if you feel I have given a complete answer, and you can leave positive feedback. Positive feedback and bonuses are always greatly appreciated!Regards,EdwardAs always when using Just Answer your accept is required for me to be paid. By accepting you are agreeing that I have satisfactorily answered your questions. If you do not accept, your deposit if applicable, will remain in your Just Answer's account until you request otherwise. Please do not accept unless you are 100% satisfied with the answer and feel you can leave positive feedback.
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