Sound on (and good) Picture off

Check and resoldered the suspected loosen part. this could happen the TV may turn normal at first to turn on after few seconds it is getting heat the suspected loosen part may totally open. resoldered the board at the secondary area near around the flyback. good luck!!

If you can solder and have good eyesight, you're in luck. That is a classic symptom of a bad solder connection leading to the base of the Horizontal output transistor, labeled Q14401 or possibly Q4401 on the printed circuit board. This transistor is mounted to a aluminum plate heat sink near the high voltage transformer with a red wire coming out of the top of it. First Unplug the set. You will then need to follow the circuit trace from the 'B' connection of that transistor back to a coil of wire labeled L14401 or L4401 and you will find that one of the two connections there will be loose. Resolder that and you should be all fixed up. You may also find a bad solder connection or two on the pins of the high voltage transformer. A good magnifier will definately help. Good Luck.