Vizio VL470M 47" LED TV minor problem...***Please Help***

[Jason Curtis]

Hi, I have a Vizio VL470M 47" LED TV and the picture is working fine but the front Vizio light is blinking white and the sound is blinking in and out in sinc with the light...Please help we dont have the money to buy a new TV....is it the main board or the power board...if it is one of these do you know a good place to buy them online so i can replace it? ***Please Help***

 

[tunedwolf]

Vizio are well known for using several different chinese manufacturers throughout their product cycles. Without close-up photos of the boards there's no real way to identify which is used in your particular TV. The issue you are having could be power supply related, or it could be bad firmware causing the inputs to switch quickly back and forth. It could also be a bad hand control. Have you tried hiding the hand control in case it is a stuck button on it? Replacing boards is not only frustrating, but gets costly quickly with these sets. There are so many of the boards used in so many different TV's, that the firmware is different enough to prevent a board meant for one TV brand, working in an identical TV of another brand. If you replace anything beyond the power board, you must ensure it is not only the board you require, but that it is intended for your exact model of TV.

 

[Jason Curtis]

I took the batteries out of the controller and checked all the buttons to make sure the ones on tv were not stuck....its so weird...I plugged it up in my back room and it stopped blinking for a sec and the sound was fine but then started again in about a minute or so. when this starts the volume up moves very slow and some of the buttons do not respond. when it stopped for a sec they all worked fine...then back to the same thing....again the picture is fine and we use our headphones on my ps4 to listen to the sound on Netflix but im worried about this because we are so broke raising our kids...I just don't get it....it just started doing this all the sudden about a week ago and its not under warranty now...I can get pics of anything in the set as I am willing to do anything to get it fixed...should I just try to fix it myself or take it to a tv repair shop and is that expensive?

 

[tunedwolf]

That's the thing, these type of buttons don't necessarily need to be physically stuck down, but the contact inside may be sufficiently made either physically or bridged by foreign matter, as to create a false press. I have seen that a couple of times when kids have had juice etc on their hands and pressed the buttons. It doesn't happen immediately, takes months, long enough after the incident that nobody remembers it happening. However, in saying that, removing the batteries would certainly rule the hand control out of the equation.

It could still be a firmware issue, or a power supply issue, or just a bad regulator or dry solder joint somewhere on the main board. You mention that the picture is good throughout the whole blinking thing. Are you certain that the backlight is not flickering in any way or that the picture is totally unaffected when it starts with the blinking LED and sound popping in and out?

If you feel confident in your ability to repair the set, your first action should be to take loads of good quality, close up photos and post them here so that we can at least attempt to identify the chassis and board manufacturer. Otherwise, I would suggest, as this seems to be your main/ only TV, that you take it to a half decent TV Engineer and let him have at it. It may cost a bit more to get him to repair it, but better that than either a new TV immediately, or worse, you spending needless money buying parts that are not faulty and then having to buy a new TV anyway.

The sound coming and going certainly hints at a power supply issue, but as the audio circuitry is usually a lower current demand, other areas of the set often show signs of distress first. That doesn't rule out a power supply issue by any means, but it may, given other clues, point you in a different direction.

Do you have some basic test equipment and tools to hand? Do you know how to use a Multimeter? Multimeter? Soldering iron? Desoldering braid? Mixture of small, insulated, screwdrivers, long nose pliers, small side snips etc? If the answer is no to any of these questions, then you really are between a rock and a hard place with this and I would say a TV Engineer would be the route to take.