I have a 48in vizio TV model # E48-C2 it keeps cutting off

@mike37hkr by this “cutting off after about 15 or 20 seconds after turning on  “ you mean it turns off? let us know if it completely turns off or if you get any power LED blinking. If so, you want to check your power board first. It could be shutting down based on components overheating or the firmware shutting it off, to protect the circuitry due to bad boards. If you need to look at those, remove the back from your TV and check for obviously damage like charred, missing or expended components. Post some images with your question so we can see what you see. 在已经存在的问题里加入图片

Right now my prime candidates would be the power board and the main board.