Causes and Symptoms
- The HDMI connection to your set-top box is bad.
- The broadcast signal is weak.
Try this
Have you checked the HDMI cable?
➔ Try reconnecting the HDMI cable to the set-top box.
Reconnecting the HDMI cable to the set-top box
Turn off the power of the TV and set-top box, disconnect the HDMI cable on the back of the TV, and reconnect it.
Also, remove the HDMI cable from the set-top box and reconnect it, if feasible.
It is recommended to use an authentic HDMI cable to connect your TV to a set-top box. (Version 2.0)
Also, remove the HDMI cable from the set-top box and reconnect it, if feasible.
It is recommended to use an authentic HDMI cable to connect your TV to a set-top box. (Version 2.0)
Does the screen flicker in all channels?
➔ Go to [Settings] and start [Picture Test] to check if the picture works normally.
Running [Sound Test] in the Settings menu
![Video test screen. [This image is a test screen. Please look carefully. Can you see the test screen well?] Message output example](https://gscs.lge.com:/gscs/support/fileupload/downloadFile.do?fileId=fftplym9hh0IjNFto4O2dQ&portalId=P1)
WebOS 5.0
[2020 WebOS 5.0] Press the 
button on the TV remote and select [All Settings] → [Customer Support] → [Additional Settings] → [Picture Test].
Turn on the TV and press the [Settings] button on your TV remote.
Select [All Settings] in the [Settings] menu.
Select [All Settings] in the [Settings] menu.
① Select [Customer Support] and then ② [Additional Settings].
③ Select [Picture Test] in [Additional Settings].
④ Perform [Picture Test] to check the screen condition.
[2019 or before] WebOS
[2019 WebOS or before] Press the 
button on the TV remote and select [All Settings] → [Picture] → [Picture Test].
Have you checked the antenna and cable TV connections?
➔ Please check the signal strength in the TV menu.
How to check the signal strength in the TV menu
Press the 
button on the TV remote and select [All Settings] → [Channels] → [Channel Search] → [Manual Channel] → [Cable DTV].
Turn on the TV and press the [Settings] button on your TV remote.
Select [All Settings] in the [Settings] menu.
Select [All Settings] in the [Settings] menu.
Select [Channels] →
① [Channel Search] → ② [Manual Channel] → ③ [Cable DTV]. (Select when using a cable TV)
① [Channel Search] → ② [Manual Channel] → ③ [Cable DTV]. (Select when using a cable TV)
④ You can see the signal strength and quality of the channel you are watching.
If there is a change of more than 30% in signal strength or signal quality, it means that the broadcast signal is unstable.
In this case, contact your property management office or broadcast service provider.
Check the antenna connection
In this case, contact your property management office or broadcast service provider.
※ If the problem persists, please contact LG Electronics service technician for further troubleshooting support.
This guide was created for all models, so the images or content may be different from your product.
