Vizio 470va have backlight but no picture

[bvcrimson]

Hi all!
I originally found this site trying to help the maintenance guy at work fix the tv in our break room. The big wigs decided to buy a new tv and I was allowed to have the broken one.

When I turn the tv on, I get a backlight and the white vizio logo and no picture. Sound is working.

From what I've found on the internet it looks like the mainboard's go bad in these tv's pretty regularly. Does this sound like what I'm running into?

Pictures to follow...

[bvcrimson]

Re: Vizio 470va have backlight but no picture

Sorry if pics aren't that great. I only have a 5.5mp phone camera.
The wife is out of town with the good camera.

[budm]

Re: Vizio 470va have backlight but no picture

You need to check the fuse (TV unplugged) and the DC voltage (TV on) at both ends of the fuse on the T-CON board (the board in the center bottom under the metal shield wit two flat cables to the LCD panel).

[bvcrimson]

Re: Vizio 470va have backlight but no picture

Is this the fuse? If so, there is no power measured there.

[bvcrimson]

Re: Vizio 470va have backlight but no picture

I checked again with a different tester and there is still no voltage at either side of the fuse.

[budm]

Re: Vizio 470va have backlight but no picture

FB is the Ferrite Bead, you will have to remove the shield to see what are under the shield.
I am not sure if the B+ is fed to that ferrite bead or not.