Sony Bravia KDL46EX402, the screen became white and no sound

you need to change the picture board/ the display board

I think fault is in electrolyte capacitor.You should check the supply volt of cathode & all relative component of RGB input.

sadly you have a bad panel. Sony panels carry a two year warranty.
your best hope is to call Sony and ask for a warranty extension to cover the cost of the part.

my tv goes white screen can i fix it..

That is only available to Sony authorized servicers. See esupport.sony.com

the most likely the t-connector board became unplugged or failed completely (sits right behind the screen modual at the top&center) or.. the logic board has went kaput on ya...ontop of that, you are dealing with the notorious sony. try and get a replacement if under warranty. do not settle for thier refurbishing.

repairing these things i can tell you , it could be anything from a bad connection or ring cracks to completely failed parts. but only if i was in it would i know for sure. but the symptoms suggest t-connector or the logic board.

biu

SOUNDS LIKE YOU HAVE A BAD LCD PANEL. TAKE IT TO A SONY AUTHORIZED SERVICER.

it's in a service test mode. have you unplugged the tv? that should reset the tv..if you still have problems after ..it will need repair.

If you can bring up the TV menu, it's probably the video board. If the won't come up, it could be the LVDS cable or the LCD panel. Either way I recommend a qualified service tech take care of this.