Vizio LED TV E48-C2 keeps turning on by itself.

Does the menu look normal or does it have lines through it?

Vizio TVs have an auto-off function intended as a power-saving feature. By default, the TV will turn itself off if it detects no signal for ten minutes. You can disable the Auto Power Off feature from the sleep timer menu.

Your done, replace the TV before you bury yourself in parts cost and labor.

Defective LED back lights strips, or damaged EEPROM on main board. I will try a main board first, if you do nor have a TV LED strip tester.

Firmware corrupted. A reinstallation is necessary. Contact any service technician.
http://electronicshelponline.blogspot.com/

how about the power supply did you check, if their is any bulged capacitors which need replacement.

Reset the TV to its factory settings. For more details, refer its user manual. Unplug the TV from AC mains socket, and replug it after some time, say after 2 minutes or so.

make sure you have not accidentaly scheduled a power off and on if yes torn off/disable them if not check that your power cable is secure

solder bad connections on power supply pcb.......T.

I had a similar problem with my 32 inch plasma tv. I called vizio's
1 800 number and the guy said to unplug the tv from the wall and hold down the power button for a minute and then plug the tv back in outlet and turn on. And it works I guess from what I understood from his heavy accent was that the tv retains power and this resets it somehow. hope that was helpfull!!