Help library: Help library: [LG TV Screen] Lines appear on the screen when an external input is selected.

[LG TV Screen] Lines appear on the screen when an external input is selected.

Troubleshooting TVS/SOUNDBARS 08/14/2025

<div oncontextmenu="return false" onselectstart="return false" ondragstart="return false" >
	<html lang="en">
<head>
<meta>
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width">
<style type="text/css">
@import url(https://fonts.googleapis.com/earlyaccess/notosanskr.css);

.tal {
text-align: left !important;
}

.ml-1 {
margin-left: 20px !important;
}

.mt-1 {
margin-top: 20px !important;
}

caption {
overflow: hidden;
width: 1px;
height: 1px;
margin: 0;
padding: 0;
font-size: 1px;
text-indent: -9999px;
}

.content-service-view {
font-family: 'Noto Sans', 'Noto Sans KR', sans-serif;
font-size: 14px;
line-height: 1.6;
}

.content-service-view .lg-red {
color: #ec455a;
}

.content-service-view strong {
font-weight: 600;
}

.content-service-view p {
margin: 0 0 10px 0;
padding: 0;
color: #333;
}

.content-service-view .txt-idt {
margin-left: 1.14em !important;
text-indent: -1.14em;
}

.content-service-view .txt-idt * {
text-indent: 0;
}

.content-service-view .iframe-wrap {
margin-top: 15px;
}

.content-service-view .iframe-wrap iframe {
width: 640px;
}

#contentsViewer .content-service-view .iframe-wrap iframe {
height: 360px !important;
}

.content-service-view .info-subject {
margin: 0 0 15px;
padding: 0;
font-size: 20px;
color: #444;
line-height: 1.5;
}

#contentsViewer .content-service-view .info-subject {
margin: 0;
padding: 0 0 15px;
}

.content-service-view .tit {
position: relative;
margin: 60px 0 15px 0;
padding: 0;
font-weight: 600;
font-size: 22px;
color: #444;
line-height: 1.5;
}

.content-service-view .tit:before {
content: "";
overflow: hidden;
position: absolute;
left: 0;
top: -8px;
width: 25px;
height: 3px;
background: #ec455a;
}

.content-service-view .tit:first-child {
margin-top: 0;
}

.content-service-view .info-subject+.tit {
margin-top: 40px;
}

.content-service-view .sub-tit {
position: relative;
margin: 60px 0 10px;
padding: 0 0 0 22px;
font-size: 17px;
font-weight: 500;
line-height: 1.5;
}

.content-service-view .sub-tit:before {
content: "";
overflow: hidden;
position: absolute;
left: 0;
top: 5px;
width: 18px;
height: 18px;
border-radius: 50%;
background: #999 url(https://gscs.lge.com:/gscs/support/fileupload/downloadFile.do?fileId=CYfUaCPKDZkbFewB3OjoAA&amp;portalId=P1) no-repeat 4px 50%;
background-size: 10px;
}

.content-service-view .sub-tit:first-child,
.content-service-view .tit+.sub-tit {
margin-top: 20px;
}

.content-service-view .sub-tit .num {
display: block;
position: absolute;
left: 0;
top: 5px;
width: 17px;
height: 17px;
text-align: center;
border-radius: 50%;
font-size: 11px;
color: #fff;
background: #999;
}

.content-service-view .info-tit {
margin: 20px 0 0;
padding-left: 20px;
font-size: 15px;
font-weight: 500;
background: url(https://gscs.lge.com:/gscs/support/fileupload/downloadFile.do?fileId=81CJtgOoS8EBzjcpk4oCvA&amp;portalId=P1) no-repeat 0 5px;
background-size: 15px;
}

.content-service-view .info-desc {
margin: 0.3em 0 0.5em;
font-weight: 500;
color: #000;
}

.content-service-view .info-desc.idt {
margin-left: 18px;
text-indent: -18px;
}

.content-service-view .img-only {
margin: 0 0 20px;
}

.content-service-view .img-only img {
max-width: 100%;
margin-bottom: 15px;
}

.content-service-view .img-only img:last-child {
margin-bottom: 0;
}

.content-service-view .img-box {
margin: 15px 0;
font-size: 0;
line-height: 0;
}

.content-service-view .img-box a {
font-size: 0;
line-height: 0;
}

.content-service-view ol,
.content-service-view ul {
margin: 0 0 20px;
padding: 0;
list-style: none;
}

.content-service-view .cause-list {
margin-top: 0;
}

.content-service-view .cause-list li {
position: relative;
margin-top: 5px;
padding-left: 10px;
line-height: 1.5;
}

.content-service-view .cause-list li:before {
content: "";
position: absolute;
left: 0;
top: 9px;
overflow: hidden;
width: 3px;
height: 3px;
border-radius: 50%;
background: #000;
}

.content-service-view .bul-list {
margin-top: 15px;
}

.content-service-view .bul-list li {
position: relative;
margin-top: 7px;
padding-left: 10px;
line-height: 1.5;
}

.content-service-view .bul-list li:before {
content: "";
position: absolute;
left: 0;
top: 9px;
overflow: hidden;
width: 4px;
height: 4px;
border-radius: 50%;
background: #ec455a;
}

.content-service-view .link-list {
margin-top: 10px;
}

.content-service-view .link-list li {
display: table;
box-sizing: border-box;
width: 100%;
margin-top: 10px;
padding: 8px 15px;
border-radius: 8px;
box-shadow: 2px 4px 16px 1px rgba(0, 0, 0, 0.14);
}

.content-service-view .link-list li .link-tit {
display: table-cell;
padding-right: 5px;
font-weight: 600;
vertical-align: middle;
}

.content-service-view .link-list li .right {
display: table-cell;
text-align: right;
}

.content-service-view .link-list li .ver {
display: inline-block;
margin-top: 5px;
color: #999;
}

.content-service-view .link-list li .right a {
margin-left: 10px;
}

.content-service-view .tbl-scroll {
position: relative;
overflow-x: auto;
margin: 0 0 15px;
}

.content-service-view .tbl-scroll table {
border-collapse: collapse;
}

.content-service-view .tbl-scroll th,
.content-service-view .tbl-scroll td {
padding: 7px;
border: 1px solid #ccc;
text-align: center;
white-space: nowrap;
vertical-align: middle;
font-size: 14px;
line-height: 1.6;
}

.content-service-view .tbl-scroll th {
font-size: 15px;
font-weight: 600;
background: #ddd;
}

.content-service-view .tbl-scroll td p {
margin-bottom: 0;
}

.content-service-view [class^="icon-"] {
display: inline-block;
overflow: hidden;
width: 14px;
height: 14px;
text-indent: -5000px;
margin-right: 2px;
vertical-align: -2px;
background-image: url(https://gscs.lge.com:/gscs/support/fileupload/downloadFile.do?fileId=e6Br68S0ipa4zVZ3ZhqQ&amp;portalId=P1);
background-size: 100%;
}

.content-service-view .icon-down {
background-image: url(https://gscs.lge.com:/gscs/support/fileupload/downloadFile.do?fileId=cSrRVKKz6eHJNHzIRgzWA&amp;portalId=P1);
}

.content-service-view [class^="btn0"] {
display: inline-block;
height: 32px;
padding: 0 15px;
border: 1px solid #ec455a;
border-radius: 18px;
text-decoration: none;
font-size: 14px;
color: #ec455a;
line-height: 2;
background: #fff;
}

.content-service-view .btn01:hover {
color: #fff;
background: #ec455a;
}

.content-service-view .link-btn {
display: inline-block;
height: 32px;
margin-top: 5px;
padding: 0 15px;
border: 1px solid #d2d2d7;
border-radius: 18px;
text-decoration: none;
font-size: 14px;
color: #ec455a;
line-height: 2;
background: #fff;
}

.content-service-view .link-btn:hover {
border-color: #ec455a;
}

.content-service-view .link-txt {
display: inline-block;
text-decoration: underline;
vertical-align: top;
color: #ec455a;
}

.content-service-view .tip-box {
margin: 15px 0 25px;
padding: 20px 22px 10px;
border: 2px solid #ddd;
border-radius: 8px;
}

.content-service-view .tip-box .tip-tit {
display: block;
position: relative;
padding-left: 22px;
font-size: 15px !important;
color: #222;
}

.content-service-view .tip-box .tip-tit:before {
content: "!";
position: absolute;
left: 0;
top: 5px;
width: 16px;
height: 16px;
border-radius: 50%;
text-align: center;
font-size: 11px;
color: #fff;
background: rgb(192, 192, 192);
}

.content-service-view .tip-box p {
margin-top: 1em;
color: #ec455a !important;
}

.content-service-view .tip-box strong {
font-size: 14px;
}

.content-service-view .tip-box&gt;p&gt;strong {
color: #ec455a !important;
}

.content-service-view .tip-box .con-view {
margin: 1em 0 15px;
color: #333;
}

.content-service-view .tip-box .bul-list {
margin-bottom: 15px;
}

.content-service-view .txt-box {
max-width: 600px;
}

.content-service-view .txt-box+.txt-box {
margin-top: 25px;
}

.content-service-view .txt-box h4 {
margin: 0;
padding: 6px;
text-align: center;
font-size: 18px;
font-weight: 600;
background: #ddd;
}

.content-service-view .txt-box ul {
margin: 0 7px;
}

.content-service-view .txt-box li {
display: flex;
flex-wrap: wrap;
padding: 5px;
border-bottom: 1px solid #ddd;
}

.content-service-view .txt-box li div {
flex: 1 1 50%;
}

.content-service-view .txt-box li span {
display: block;
position: relative;
padding-left: 10px;
font-size: 16px;
font-weight: 600;
}

.content-service-view .txt-box li span:before {
content: "";
position: absolute;
left: 0;
top: 10px;
overflow: hidden;
width: 4px;
height: 4px;
border-radius: 50%;
background: #000;
}

.content-service-view .txt-box li p {
margin: 0;
padding: 0 0 0 10px;
font-size: 15px;
}

.content-service-view .img-banner {
margin-top: 2em;
}

.content-service-view .img-banner .mo {
display: none;
}

.content-service-view .img-banner .pc {
display: block;
position: relative;
height: 168px;
margin-right: 175px;
background: #e9ecf1 url(https://gscs.lge.com:/gscs/support/fileupload/downloadFile.do?fileId=EYElckJimMpH2v7UAxQSvw&portalId=P1) no-repeat 0 50%;
background-size: contain;
}

.content-service-view .img-banner .pc a {
position: absolute;
top: 0;
right: -175px;
}

.content-service-view .img-banner .pc a img {
-webkit-box-shadow: 2px 2px 5px 0px rgba(118, 118, 118, 1);
-moz-box-shadow: 2px 2px 5px 0px rgba(118, 118, 118, 1);
box-shadow: 2px 2px 5px 0px rgba(118, 118, 118, 1);
}

.content-service-view .ir-hidden {
position: absolute;
margin: -1px;
width: 1px;
height: 1px;
padding: 0;
border: 0;
white-space: nowrap;
overflow: hidden;
clip: rect(0, 0, 0, 0);
clip-path: inset(50%);
}

.content-service-view .mobile-txt {
display: none;
margin-top: -10px;
padding-left: 20px;
color: #999;
background: url(https://gscs.lge.com:/gscs/support/fileupload/downloadFile.do?fileId=Xw5rvb0UTyjfo1LwHfIJ7w&amp;portalId=P1) no-repeat 0 5px;
background-size: 15px;
}

.content-service-view .help-txt {
position: relative;
margin: 30px 0 0;
padding: 0 0 0 15px;
font-size: 13px;
color: #666;
}

.content-service-view .help-txt:before {
content: '＊';
position: absolute;
left: 0;
top: -1px;
font-size: 12px;
font-weight: 600;
color: #ec455a;
}

@media screen and (max-width: 768px) {
.content-service-view img {
max-width: 100% !important;
}

.content-service-view .mobile-txt {
display: block;
}

.content-service-view .iframe-wrap {
position: relative;
overflow: hidden;
height: 0;
padding-top: 30px;
padding-bottom: 56.25%;
}

.content-service-view .iframe-wrap iframe {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 90% !important;
}

#contentsViewer .content-service-view .iframe-wrap iframe {
height: 90% !important;
}

.content-service-view .iframe-wrap+.tit {
margin-top: 0;
}

.content-service-view .img-banner .mo {
display: block;
}

.content-service-view .img-banner .mo img {
width: 100%;
}

.content-service-view .img-banner .pc {
display: none;
}
}
</style>

</head>

<body>

<div class="content-service-view">
<p class="info-desc">
Original Screen Mode is an option that enables you to view high-definition videos at the highest quality without any loss.<br>
This option can be selected when there is a high-definition video signal coming from a digital TV or HDMI port.<br>
The Auto Aspect Ratio feature automatically adjusts the aspect ratio of the TV screen based on the input video signal.<br>
The modes available are 4:3 and 16:9, which are automatically selected according to the input signal.<br>
If lines appear on the screen, it may indicate incorrect TV input signal or screen size settings.
</p><p class="txt-idt">※ The method for adjusting the settings and the availability of adjustment menus may vary depending on the TV model.</p>        
<h2 class="tit">Causes and Symptoms</h2>
        
<ul class="cause-list">
            
<li>Lines appear on the screen.</li>
        </ul>
        
<h2 class="tit">Try this</h2>
        
<h3 class="sub-tit">If lines appear on the screen while using an external input, please check the following:</h3>
        <p class="info-desc idt">➔ If the lines do not appear when the TV is switched to a different external input, the problem might be due to incorrect TV external input signal or screen size settings.</p>        <p>The screen size can be personalized in the Easy Setup menu.</p>        
<h3 class="sub-tit">Check the TV settings and make sure that the [Screen Size] mode is set to 16:9.</h3>
        <p class="info-desc idt">➔ Lines may also appear if there is an issue with the antenna signal or cable.</p>        <p>Check the cable connection and replace the cable if it is damaged.</p><p class="help-txt">This guide was created for all models, so the images or content may be different from your
product.</p></div>

</body>
</html>
	
</div>

*Required question

Article Feedback Article Feedback

1. Was this information helpful?*

Please fill out the required field.

YES NO

Need immediate help?

2. How would you improve the information?*

Please fill out the required field.

Characters left : /

Submit

Thank you for your feedback!

Help library

[LG TV Screen] Lines appear on the screen when an external input is selected.

Contact