Hello, If you're certain it's not the TV's Input setting, or a single HDMI port (meaning you've tried more than one port on the TV, as well as more than one HDMI cable - even IF the same cable works on another set - that is not a conclusive test, as we see one cable work on 2 sets and not a 3rd in MANY CASES), then this would point directly to your Vizio's Mainboard.
The only way to tell which Mainboard your set uses is to remove the back of the set and pull the part number off the board. This is common with Samsung, Vizio, LG and many other sets since the manufacturer will make revisions to the boards without notifying anyone. The part number must match the one in your set to be certain you purchase the correct Mainboard. Even pats sits like Shop Jimmy and TV Parts Guy state this on their sites to order by "board number" instead of model number - for that very reason, so unfortunately there is no way to make sure with 100% certainty that you get the correct board, without removing the back of the TV to verify.
If you need further assistance let me know. Before you go, PLEASE DO click at least a 3 STAR RATING, at the top of your screen. That is how I am credited for my efforts by the site. You can follow up any time as needed at no additional cost.
I have no private board sources. Everything is on Google. Did you Google search using the board number? If not, I would strongly suggest doing that to find more options to purchase it.
They're showing as out of stock through TV Parts Guy as well:
Actually, my bad. If you scroll further down the page there are a couple in stock options.
It's impossible for me to do a postmortem, but in general electronics don't give much warning when they fail, it's simply the nature of the beast. Something can work one minute, a chip gives up and it goes out. Heat, use, wear, cheaply made Chinese parts, etc. can all be culprits.
You're welcome. I'm not sure if you saw my post above, but TV Parts Guy was showing some options about halfway down that page as well.
Let me know if you need more help. Also, could you please click a POSITIVE RATING (3-5 stars at the top of the page) and click SUBMIT so that I am credited for working with you today?
Do you need further assistance with this?
Hello, I was just following up to see if you needed further help? The site shows that since the question is open that you are still looking for help. Or, if you received the information you were looking for-could you please kindly rate my service POSITIVELY (by clicking a 3-5 star rating by scrolling to the top of the page)? Thanks in advance.