Help Phone reboots it goes into sleep mode help!!

[Novoken]

So my phone has been working fine, but just today its keep rebooting on its own. When its goes into sleep mode it will restart. When I take out the bat and put it back in it will turn on on its own as well. I cleared the cache. Same problem. I uninstalled a bunch of apps but still the same thing..

ver 4.1.2

 

[Gendo420]

Turning on on its own like that is a sign to power button failure, which would also account for rebooting like that.