Vizio TV Half Screen Dark? Fix in Minutes

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There’s two main causes as to why your Vizio TV has a half dark screen, and the good news is that both issues are fixable at home if you are willing to put in a little work.

The problem can be seen as either a black shadow on your Vizio TV, the top half of your TV screen is dark, there is a dark band across your Vizio TV or your Vizio TV is dark on one side.

Whichever of these your TV is suffering from, I’ll cover all of the proven fixes below, to get you back up and running as soon as possible.


vizio tv half screen dark

How to Fix Vizio TV Half Screen Dark

If your Vizio TV is dark on one side, fix it by either replacing any failed LED backlights or re-soldering any faulty connections between LED strips, or add strips of tape to the ribbon cable connecting the T-Con board to the panel to block any faulty clock signals.

Because people mean different things by “Vizio TV half screen dark”, or “Vizio TV dark on one side”, the issue can be caused by a couple of different problems, both of which have different solutions.

For example, a dark band across your Vizio TV is caused by a backlight issue, while either the left or right hand side of the TV screen being totally blank is likely a T-Con issue.

And if you see flickering, then look at my article on how to fix Vizio TV flickering screens, while if your TV doesn’t seem to be getting power, then check out Vizio TV won’t turn on article.

We’ll cover every possible fix below, but make sure you read the description for each carefully so that you can match the correct fix to your exact problem.


1. Power Cycle Your Vizio TV

You want to be sure that half of your screen going dark is caused by a hardware, rather than a software issue, so the first step is to power cycle your TV.

Power cycling your TV will clear out any issues with non-permanent memory without losing your personal settings.

  1. Unplug your TV.
  2. Hold down the physical power button on your TV for at least 15 seconds to drain any residual power from the capacitors.
  3. Leave your TV unplugged for at least 30 minutes.
  4. Plug it back in and switch back on. The power light should come on.

nb. Make sure that you hold down the physical power button on your TV, not the one on the remote.

vizio tv power button

Although this might seem a basic step, it’s surprising how often power cycling your TV will help to fix it.


2. Confirm Your Wall Socket is Properly Supplying Power

Because flat screen TV’s rely on a constant power supply, when there are fluctuations in voltage these can show up as inconsistencies with the backlight, causing dark areas on your TV.

If your TV is on, then you know that your wall socket is suppplying power, but the question is whether this is constant without fluctuations and is of a sufficient voltage.

The most common cause of low voltage from wall sockets are faulty surge protectors.

If you don’t have a wall socket testing rig, then just unplug your TV, remove any surge protectors and try another appliance that you know draws a similar current. Check if this works as expected.

You can also plug your TV into another wall socket, preferably one located on the other side of the room from the current socket, again without any surge protectors or consumer extension cords that you might be using.


3. Return Under Warranty

Although the two steps above are unlikely to have fixed your TV screen, they are worth trying because the next steps involve physically opening up your TV.

Before trying anything that involves taking your TV apart, check whether you are still in warranty.

Removing the back panel from your Vizio TV will void its warranty, so if you have bought it in the last year, then you are best to contact Vizio support and get them to either fix or replace your TV.


4. Check Backlight for Dark Areas On Screen

vizio tv screen darker than normal

If you are seeing dark areas on screen, or either the top half, bottom half, left side or right side is darker than its counterpart, or your Vizio TV screen is darker than normal, then you have a backlight issue.

Backlights on modern Vizio TVs come in LED strips of varying lengths. Older models used lengths that spanned the entire frame of the TV, but due to cost savings, more recent TVs use a set 16″ LED strip which is connected in series for each row to span your TV.

These cold soldered connectors are a notorious failure point on Vizio TVs, but can be easily fixed if you are willing to re-solder a joint yourself.

Equally commonly, the LED backlights themselves can fail. This is due to repeated current over powering, which over time causes thermal degradation of the LEDs leading to burnout. You can replace any failed LEDs by just removing the entire strip and replacing it.

The problem with fixing the LEDs is that they are located in the most difficult to access part of your TV. So if you are not comfortable with a larger repair job, then now is a good time to seek help from a professional.

You need to remove the back panel, remove all of the circuit boards and connectors, then another layer of screws for the front panel, and only when you have fully removed the LCD panel can you get to the backlights.

You will also need a multimeter to test the backlight strips to find out where the problem lies.

tv led lights
Replacement LED backlight strips

To fix a failed backlight:

  1. Unplug your TV, hold down the power button and wait for at least 30 minutes. There are large capacitors in the power board for the backlight and these can hold charge for an extended period of time.
  2. Place your TV face down on a large table or workbench. Make sure there is nothing that can scratch the screen on your work surface.
  3. Ground yourself.
  4. Open your TV by unscrewing the screws in the backpanel. It should come apart in two pieces: front and back.
  5. Put the back panel somewhere out of the way and take a look at the circuit boards that have been revealed.
  6. You will see a T-Con panel for translating the signal into a TV picture, a power board and a main board. Any wires or ribbons that are near the edge of the TV should be disconnected.
  7. Then remove the screws around the edge that hold the bezel of the TV.
  8. With some care, you should be able to remove the bezel, panel and reveal the TV backlight underneath, which will be in strips of LED lights.
  9. Use a voltmeter or TV backlight tester to check whether they are working, and replace any failures.

The video below covers checking and replacing the LED backlights, with some additional tips on when you should seek to replace your backlight driver board instead.

It’s also possible that one of the connectors linking the LED strips as they span the width of your TV has failed. This can be fixed by checking the connectors with a multimeter and re-soldering and broken connections. This article has a good study on this.

Rarely, the backlight issue can be caused by a faulty main board. You can follow the next step to identify it, clean the contacts going into it and replace it if necessary.


5. For Half Your Screen Being Black, Check Your T-Con Board

If either the left or right hand side of your Vizio TV screen is totally black, extending from the edge to the center or your screen, then there is a problem with your T-Con board or the cabling connecting it to your screen.

The Timing Control (T-Con) board is a small PCB board that drives your TV’s panel, translating the signal into a picture on your screen.

It’s hidden away under the back panel, behind the screen, and is the cause of a half black TV screen because it connects to the LCD / OLED panel with ribbon connectors which can come loose or get covered in grime or dust, impeding their contact.

vizio tv t con ribbon cables

To access the T-Con board, you need to remove the back panel. If you’re not confident doing this, then now is the time to get an expert in. Otherwise:

  1. Unplug your TV, hold down the power button and wait for at least 30 minutes. There are large capacitors in the power board for the backlight and these can hold charge for an extended period of time.
  2. Place your TV face down on a large table or workbench. Make sure there is nothing that can scratch the screen on your work surface.
  3. Ground yourself.
  4. Open your TV by unscrewing the screws in the backpanel. It should come apart in two pieces: front and back.
  5. Put the back panel somewhere out of the way and take a look at the circuit boards that have been revealed.
  6. You will see a T-Con panel for translating the signal into a TV picture, a power board and a main board.

Or see this in action in the video below.

The position of the boards will vary by model, but the T-Con board can be identified by the ribbon cables connecting it to the TV’s panel. Identify the main three boards you will see in the images below.

tv main board
tv power board
tv t con board

Start by giving everything a good clean, preferably with compressed air or a non-static brush. It’s possible that dust in the connections can block the signal.

Then, you should be able to remove the cables on the T-Con board by pushing the locking cover down and they will then easily come away from the board. Don’t try to force them out without unlocking them first.

removing t con cable
Push the locking bar to remove the T-Con ribbon cables

After removing the ribbon cable, take a look at the individual connectors on the ends of the cables, and the connectors in the socket. You are looking for any signs of corrosion, damage or dust.

The contacts should be a shiny gold or silver color. If they are dull and appear to have a rough, copper-like layer over them, this would indicate oxidation and therefore a new cable is recommended.

t con cable
A T Con cable in good condition

Give the cable and socket a good clean with compressed air, then put the cable back in, put the back panel back on your TV and fire it up.

If half the screen is still black, there’s a good chance that there is a fault somewhere on the T-Con board itself. These can be replaced for around $30 from eBay.

To get the correct board, note the T-Con model number written on the label on the board, and put this into eBay.

But before you replace the T-Con Board, try the final step which can fix faulty boards without you needing to replace them.


6. Block the T-Con Signal with Tape

This might seem like a bit of a hacky approach, but it is possible to use small pieces of non-conductive tape to block the indiviual contacts on the T-Con cable.

This blocks the “bad” signal getting sent through that contact, and can actually clear up the image.

This works because the T-Con cable sends a clock signal through a handful of the pins (usually 8 pins per cable) which is implicated in the most common issues of half your screen going black.

And with two cables, one for each side of the TV, you can use the signal from the working side of the T-Con board to fill in for the faulty clock signals on the other side.

This method can also work well for fixing horizontal lines on a Vizio TV.

It can take some trial and error to get this right, so I recommend you check out the video below for a good demonstration of how to follow this approach.


Final Thoughts on How to Fix a Vizio TV With a Dark Half Screen

There are a couple of main causes for a half dark screen on your Vizio TV, but these can be fixed by following the steps below.

  1. Power cycle your Vizio TV.
  2. Confirm your wall socket is supplying consistent power.
  3. Return under warranty.
  4. Replace any burned out LEDs in the backlight, and re-solder any poor connections in the backlight strips.
  5. Clean and replace the T-Con board if half the screen is totally black.

Let me know if this helped in the comments, and let me know if there’s anything else you need help with!


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Hi, I'm Tim Daniels, photographer and photo trainer, founder of Lapse of the Shutter and creator of the totally free Lightroom Develop System. I've travelled to (probably) 30 countries over the last few years, taking photos and licensing them around the world, and creating lots of free photography learning resources. Read More ...

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