phone randomly turning itself off

[vrelron]

My phone always turns off every so often i noticed it happens only when wifi or 3G is turned on it does not happen when i put my phone in the charger

[Thommo]

Check your SIM card is correctly seated and free from dirt etc - Also is your card a correctly manufactured one or have you cut it down to size? as a loose fitting or ill fitting SIM card will do this

[vrelron]

I tried taking the SIM out and replace it, did not work I made sure that my SIM was clean and did not work, I tried it without SIM in the phone and it keeps turning off

[Thommo]

Sorry to say but in circumstances like this you need to either return your device to the place of purchase or contact Xperia care http://www.sonymobile.com/global-en/support/contact-us/

[vrelron]

I found out what the problem was the conection with the battery is broken and I am having it repeared but thank you for the help