Its Not At All A Hardware Problem. Since White Screen Comes Up, It Means You Hardware Is Perfect.
Download WotanClient From Online de-branding and software upgrade service SonyEricsson (SE) mobile phones | WotanServer.com And Let The Client Update.
Now Clear The User And Password Fields And Hit Start.
Then Plug Your Phone By Pressing 2+5 Keys Instead Of c.
In 11 seconds, Your EROM Will Be Updated And Your Phone Will Most Probably Work. Next, Although Your Phone Will Work Fine, Still You Will Need To Flash Your Firmware To Prevent This Cause In Future. Be Carefull Because Next Time You Get This Problem. Wotan Wont Flash Your EROM And You Phone Will Be Incurable.
Tell Me Any Further Details As You Go.