
All you want is to sit down and unwind while watching your favorite shows.
But instead of seeing the usual crisp resolution of your LG TV screen…
You find that one side is weirdly darker.
Oh-uh…
Now what?
You’re in luck, as you found the right website.
Read on to find out:
- How to effectively run LG TV’s self-diagnosis.
- 5 easy fixes to do when half of your LG TV screen is darker.
- Whether loose wires are causing this and how to clasp them together.
- And we’re just getting started…
Why is half of my LG TV screen dark?
Half of your LG TV screen is dark because of loose wire connections. To fix this, you need to check your HDMI cables, input sources, and the T-CON board inside your TV. On rare occasions, the cause is faulty LCD panels or motherboards, which are trickier to fix.
LG TV half screen darker: 5 fixes
#1: Do a quick power cycle
Before you try to change anything in your LG TV…
Try to do a quick power cycle.
“I already restarted my TV earlier. But it didn’t work.”
Well, a restart isn’t the same as a power cycle.
A restart simply turns your TV off, but it doesn’t drain its power.
Think about it…
When you restart your TV, it’s still plugged into your outlet, right?
But in doing a power cycle, your goal is to drain all the power in your TV.
“How would this help fix my dark screen?”
To answer that…
Inside your TV, some capacitors store power.
And sometimes, when there’s an occurring issue…
Capacitors store the information of the problem just like they store power.
And as long you don’t drain the power…
Your TV will keep repeating on showing a half darker screen.
So how do we fix this?
Lucky you, it’s easy to power cycle your LG TV.
How to conduct a power cycle:
- Power off your TV.
- Unplug it from the outlet.
- While unplugged, press the power button for 10 seconds.
- Wait for 10 minutes.
- Plug your TV again and turn it back on.
If the issue still exists, proceed and…
#2: Check the HDMI cable

HDMI cables transmit the video from your input source to your TV.
So it goes without saying that…
A faulty HDMI cable can also cause a faulty transmission to your screen.
But rest assured. Checking HDMI cables is an effortless task.
Plus, if you have a post-2018 LG TV model, this step will be even easier for you.
Modern LG TVs have their own self-diagnosis function.
If you have a post-2018 LG TV:
- On your remote, long-press the #9 button.
- Click on Optimization settings.
- Review the overall status of your TV.
- If there are no issues, go back to the previous screen.
- Select Check Items.
- Click on Check the Status of TV.
- On the list that shows, select RF/HDMI.
- Select Start Diagnosis.
If there’s a problem with your HDMI cable connection, it will show up in the diagnosis.
But if your smart TV remote isn’t working, or you have an:
Older model:
- Unplug the HDMI cable from your TV.
- Unplug the HDMI from your input source.
- Check for any visible signs of damage.
- If there’s no damage, plug one end back into the TV.
- Insert the other end to your input source.
If one side of the screen is still darker, try using a different HDMI cable if you have one.
A high-quality HDMI cable is crucial in having a high-quality streaming experience.
So if you’re using a standard or old HDMI cable, I suggest you invest in a higher-quality one.
In cases when the HDMI cable isn’t the problem, the next fix is to…
#3: Change external factors
Sometimes when LG TVs have a problem…
The issue isn’t really the TV but the external devices that connect to it.
“What external devices?”
I’m talking about input sources like a cable box or a streaming device like Roku.
To check, you can connect a different input source to your TV.
So I’ll teach you how to do that…
To change your input source:
- Turn OFF both your TV and your input device.
- Unplug the HDMI cable from the device you’re using.
- Choose a different input source like a laptop, phone, or PC.
- Plug your HDMI cable to the HDMI port of your chosen input source.
- Turn both the TV and your new input source ON.
You might also want to know: How To Connect a Non-Smart TV to Your Phone?
If your input device is the problem, this will fix the issue.
But if it’s not, you might need to…
#4: Clasp loose wires together
“You mean I have to open up the TV?”
Luckily, this method doesn’t require that.
This method is often overlooked.
But believe it or not… it’s also one of the most effective fixes.
And to clasp loose wires together…
You have to clap your hands with the TV in the middle.
No joke.
Let me guide you through the process.
Here are the…
Steps to clasp loose wires together:
- Keep your LG TV open.
- Stand on the dark side of your LG TV screen.
- Place one hand on the back of the upper corner.
- Place the other hand in front of that corner.
- Clap your hands together gently with the screen’s corner in between.
- If this doesn’t fix the problem, do the clap again, with more force.
- Check if your screen is fixed.
If the TV still isn’t fixed, you might need to…
#5: Inspect your T-CON board
If you’re thinking…
“I guess I need to open my TV this time.”
You’re right.
Unfortunately, if the previous methods don’t work…
You have no choice but to check your TV’s T-CON board.
And the only way to access your T-CON board is to pry your LG’s back cover open.
Warning: Proceed only if you know the dangers and risks of opening up your TV. If you have no prior experience in fixing circuit boards, I suggest getting assistance from your local technicians.
What you need:
- Latex gloves.
- A screwdriver.
- A magnifying glass.
Warning: Never use a metal object to lift up any components inside your TV. Even a simple scratch or slip can permanently damage your LG TV.
To open your LG TV:
- Lay your TV down on a soft surface.
- Carefully detach the back cover of your LG TV.
- Disconnect any cables that connect your cover to the circuits.
To inspect the T-CON board:
- Locate your T-CON board.
- Find the LVDS cable, which has multiple thin wires attached.
- Detach the cable.
- Use a magnifying glass to inspect each pin.
- If there are no damages, insert it back again.
- Reseat the ribbon cables.
- Ensure that there’s no dust or debris on your board.
If your LG TV only has minor problems, this should fix the dark screen issue.
But if the problem still exists…,
BONUS: It’s time to replace your TV
If the T-CON board isn’t the problem…
There could be an issue with your motherboard or LCD panels.
And for both cases…
It might be better to buy a new TV instead.
LCD panels, in particular, are very tricky to work with.
Others have tried fixing them only to lose their TVs in the process.
So if it’s been quite some time since you got your TV…
And if recently, your smart TV has been so slow anyways…
It might be time to let it go and gift yourself a new one instead.