what causes pcb failure? ~ Sharp LC-60E69U

[mojointn]

So my Sharp LC-60E69U just up and quit working. No sound no picture no lights. I changed the power control board. Plugged it in and the power light lit up. Waited about a hour and turned it on. It took like two minutes to get a picture. Watching it for ten minutes turned it off then came back hit the power button and the power light went off again. Pcb again... what would cause pcb failure?

 

[hang-the-9]

That's like asking what can cause any electronic failure. Heat/cold flex, failed components, electrical surges or unstable voltage.