Green vertical line on 55" Vizio TV?

Sounds like a defective TV. May be something is wrong with the connections, but my advice would be to take it back and get a replacement. A brand new TV should not have any defects!

Oh NOOOOOOOOOO

Is it the same on all channels?
Do you have a computer or DVD player with HDMI, maybe it’s the cable box?

My dad had the same issue with his tv. After a bit of playing around we figured out it only happened when the tv was hot. Doesnt sound like your issue though. Id call vizio about it.

From the information you provided the TV, the HDMI cable, or the cable box could be the cause. Is there a setting within the TV to select the input source? Perhaps the correct input isn’t selected. Do you have another HDMI cable that you can test with to see if the problem disappears? Same question with the cable box? Also, does the cable box have an output setting that can be changed?

The thing is to isolate the problem. Determine the source of the problem. Then you’ll have your answer.

This assumes the following : 1) the line is sharp 2) the line never moves 3) the line is always there.
The short answer is, “it is in the display electronics driving the flat panel array”. This means it is irreparable “in the field”. Meaning anywhere but factory.
The long answer is to explain the workings of the display drive electronics, but the net answer is the same…....
It is possible that the problem will only occur at certain temperatures or other specific conditions, but the net answer is also the same.
If this is under warranty, it will be a new TV, since the panel will not be a shop replaceable item.

Since you say the line is on the right hand side and goes away then it is not the panel electronics, but more likely in the video that you are feeding it. if there is not enough information, or picture to fill the entire width of the screen, the vacant signal area could be anything, not uncommon to see green.
If the HDMI cable is really the problem it could be affecting the signal in timing, lots of this kind of thing can be seen on computer monitors with longer vga cables, the length of the cable causes signal degredation and image blurring, as well as lines of this type. Since the sync signal is often embedded in the green color signal it is most likely this color you will see.
the component signals are much easier to send longer distances thru cable, because of the design impedance of the component system – so they are less likely to have a cable length problem. I might suggest a high grade HDMI cable; there are cheaper cables which could cause this problem too. For the sake of signal, this can be the weakest link so its best to spend a good coin on it.
Hope this has covered most of the bases for you.
Good Luck.