Vizio M421VT LED faulty!

[silva1955]

Hi guys; i need your help on this Vizio M421VT LED TV, one of my last finds,and i'm trying to save it from going to landfill;
i have this screen pic,
also there is no sound.

http://postimg.org/image/b1s2lk0zx/ae269042/

[silva1955]

hi guys; has anybody here an idea of my issue, it's like as if my video is scrambled by the provider.
all voltages from power supply are ok.


 

[downunder]

My money would be on the main board, possibly poor ball joints on the BGA chip. Try heat on the metal can.

Bruce

[silva1955]

Thanks downunder:Update on this Vizio M-421VT Led display, i have made a Utube video,i've got hold of a remote control and was able to set chan-3 and i get sound and the scrambled pic.
sometimes when i plug from the wall it gets the vizio logo blinking then a few pugs in and out from the outlet i can get pic scrambled and sound,
well i would be happy if it was not the screen, no money now for a main board that is being sold for 130 dollars which is out of the question for now,maybe i come across a cheaper a board in the future









https://www.youtube.com/watch?v=YiSs0lPw6RY

[downunder]

Looked at your video. Doesn't look to be panel or T-Con. The fact that you can't turn it off by remote, makes me more certain that it's the main board, so keep looking.

Bruce

[silva1955]

Thanks Downunder; i Follow your advice  on the BGA chip heating and it payed off,it's running, i don't know for how long,
i applied  the same method as the Ps3 YLOD fix tutorial just by heating first bottom side with low heat then with high heat the heat sink , let it cool for an hour then put it together and voila it's running for now,i also made a hole in the Plastic behind the Heat sink and  added 2 small 5 v fans connected to USB.

Thanks for the help clue, appreciate.

[downunder]

Well, well, well. That's positive feedback. Isn't Vizio made by LG? We have a high degree of success by baking LG main boards for 10 minutes in a 200 degree oven. Seems to remedy a host of ailments, but strangely only seems to work on LG boards. Good work.

Bruce

[Turnip]

Hi Bruce and well said,

Have a thought though - ovens, even new ones aren't precise temperature wise. Tried it with a dubious board at 200C and the wife wondered what all those little Black things were at the bottom of the oven.

As mentioned at the time, the oven was only a couple of weeks old, so would suggest using an oven thermometer clipped to the rack used and when 200C is achieved, turn the oven off and slip in the panel for 10 minutes.

Just a thought - Chris.

[silva1955]

Thanks guys,about Oven Heating the Main board?  isn't   that a big risky? cause you're gonna  heat all the components,and some of the them are too sensitive to too much heat!, i still think heating the BGA heat sink is a lot more safer!

[Turnip]

Hi Silva,

Would suspect just because oven temperature was wrong, It isn't such a bad idea.

Relied on the oven, as was a new one to sort 200C but guess as bits fell off it wasn't accurate as not made for the job - More for cooking food.

Suspect if used a thermometer on the shelf and turned off when it got to temperature, Shoved in the panel for ten minutes - wouldn't have had the problem - Chris.

[downunder]

Hi Chris,

Don't you sit the board in an oven tray? Mind you my oven isn't exactly pristine, so I don't notice. Ovens aren't made to be cleaned - cleaning ovens is worse than latrine duty.

Mind you, I just cooked a cheapie TCL main board that had intermittent sound, and the RCA sockets took a bit of a beating. Had to drill the holes out due to partial closure. Might go for 9 min @ 180 degree next time. Sorted the sound problem, though.

Just a thought, Bruce