Black Lines On Samsung Tv Screen- How To Fix? | Fix Steps

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Black lines on a Samsung TV screen usually come from the signal path, picture processing, or the panel itself; a couple of quick tests tell you which.

Seeing a sharp black line (or a stack of lines) can make any show feel unwatchable. The good news is that you can sort most cases into three buckets in under ten minutes: an external source or cable issue, a TV setting or software hiccup, or a hardware fault inside the screen.

This guide walks you through a clean, low-risk path that starts with the easiest checks and ends with the “stop here” signs that point to a repair.

Fixing Black Lines On Your Samsung TV Screen At Home

Start by answering one question: do the lines show up on the TV’s own menus and built-in test images, or only when you watch a specific device like a cable box, console, or streaming stick?

Check The Source In 60 Seconds

  1. Open The TV Menu — Press Home/Menu and see if the black lines sit on top of the menu, apps, and settings screens.
  2. Switch Inputs — Move from HDMI 1 to HDMI 2, then to Live TV or an internal app like YouTube to see what changes.
  3. Pause On A Solid Screen — In an app, pause on a plain scene or bring up a settings page so the line is easy to judge.

If the line vanishes when you change inputs or apps, you’re likely dealing with the device or cable feeding the TV. If the line stays on all screens, keep going with the built-in tests.

Run The Built-In Picture Test

Most Samsung TVs include a self-diagnosis picture or pixel test that displays internal patterns. If the line shows during that test, the TV is drawing the line on its own, which usually points away from HDMI devices and toward the screen hardware.

If you want to see the on-screen path on a recent Samsung menu, this official Samsung US video shows the self-diagnosis flow: Samsung TV self-diagnosis steps.

Use This Quick Triage Table

What You See What It Usually Points To What To Do Next
Lines only on one HDMI device Cable, port, or that device’s video output Swap HDMI cable, try a new port, change the device resolution
Lines vanish in TV apps, show on set-top box External source or handshake issue Power cycle both devices, reset HDMI settings on the source
Lines visible on menu and picture test Screen panel, internal ribbon, or processing board Do the safe resets, then plan service if it persists

Fixes When The Lines Come From HDMI Or Another Device

When the black lines appear only on a console, cable box, or PC input, treat it like a signal problem until proven otherwise. Small connection issues can create odd artifacts that look like panel damage.

Reset The HDMI Connection Path

  1. Unplug The HDMI Cable — Remove it from both ends, then plug it back in with a firm click.
  2. Try A Different HDMI Port — Move the same cable and device to another port to rule out a single bad jack.
  3. Use A Different HDMI Cable — A cable with a bent pin or weak shielding can cause streaks or flicker lines.

Power Cycle The Source And TV Together

  1. Turn Off Both Devices — Shut down the TV and the connected device, then unplug both from power.
  2. Wait A Full Minute — Let the internal capacitors drain so the HDMI handshake starts clean.
  3. Reconnect Power, Then HDMI — Plug the TV in first, power it on, then power the source and connect HDMI.

Match Resolution And Refresh Rate

Some black line patterns show up when a device is pushing a video mode the TV struggles to lock on to. This is common with PCs and game consoles set to unusual refresh rates.

  • Set Output To 1080p Temporarily — If you’re on a console or PC, drop to 1920×1080 and test again.
  • Turn Off Variable Refresh Features — Disable VRR or similar modes on the source and see if the line disappears.
  • Use Standard Color Format — Try 8-bit color and a common RGB/YCbCr setting instead of a forced mode.

Rule Out A Single App Or Channel

If the line appears only on one streaming app, update that app, sign out and back in, then test a different stream. If the line appears only on one TV channel, the broadcast feed may be the culprit.

Fixes When The Lines Show Up On The Menu Or Picture Test

When the line sits on top of all screens, you’re now testing the TV itself. The goal is to clear settings glitches and software corruption, then decide if the panel is failing.

Do A Safe Power Reset

  1. Unplug The TV From The Wall — Don’t just turn it off with the remote.
  2. Hold The TV Power Button — Hold the button on the TV (not the remote) for 15–20 seconds.
  3. Wait Two Minutes — Plug it back in and test again on the Home screen.

Reset Picture Settings Without Wiping The TV

A corrupted picture mode setting, aspect ratio, or processing option can produce lines that look hardware-related. A picture settings reset is a low-risk move because it does not erase your apps or accounts.

  1. Open Settings — Go to Settings, then Picture.
  2. Reset Picture — Choose the reset option for picture settings (wording varies by model).
  3. Test On A Built-In App — Use an internal app so you’re not mixing in HDMI variables.

Turn Off Extra Processing Features

On some models, a processing feature can glitch and create banding or straight lines. Try disabling one feature at a time so you can spot the change.

  • Disable Motion Smoothing — Turn off Auto Motion Plus or motion interpolation options.
  • Disable Noise Reduction — Switch off digital noise filters and test a clean stream.
  • Set Picture Size To Standard — Pick “16:9” or “Fit to Screen” defaults and avoid custom zoom.

Check For Firmware Updates

Samsung regularly ships firmware that fixes display bugs, HDMI handshake quirks, and app stability. If your TV is online, check for updates in Settings, then Software Update.

Pick A Certified Cable If You Use 4K 120Hz Or VRR

If your line appears only in high-bandwidth modes (4K 120Hz, VRR, or certain HDR setups), the cable is a common weak spot. HDMI Licensing Administrator explains Ultra High Speed cable labels and what they mean here: Ultra HDMI cable types and labels.

When Black Lines Mean A Panel Or Internal Connection Fault

If the black line is present on the TV menu and the picture test, and none of the safe resets change it, the odds shift toward hardware. The most common causes are a failing LCD/OLED panel section, a ribbon cable that has loosened inside the set, or a fault on the board that drives the panel (often called the T-Con on many LCD models).

At this point, the goal changes. You want to avoid risky DIY moves that can crack the panel, then gather clean notes that make a service request faster.

Spot The Patterns That Usually Mean Hardware

  • One Thin Line That Never Moves — A single vertical or horizontal line that is always in the same place is a common panel-column or row driver failure sign.
  • Thick Banding Or Multiple Lines — A block of lines, or a wide dark strip, can point to a ribbon connection or panel section fault.
  • Lines That Change With Heat — If it’s worse right after power-on and eases later, an internal connection may be marginal.

Do These Safe Checks Before Booking Service

  1. Remove All External Devices — Unplug each HDMI and antenna cable, then test only the Home screen and picture test.
  2. Try A Different Power Outlet — Plug into a wall outlet, skipping power strips, to rule out power noise.
  3. Capture Clear Photos — Take a photo of the line on the menu and on the picture test pattern for documentation.

Avoid opening the back panel unless you have TV repair experience. Ribbon cables and panel tabs are fragile, and a slip can turn a fixable issue into a full panel replacement job.

Repair Choices: Warranty, Service, Or Replace

Once your tests point to hardware, you’re choosing between service, warranty terms, or replacement. The right call depends on age, model tier, and the cost of parts.

Know What To Ask For When You Contact Samsung

When you reach Samsung service, you’ll get faster routing if you can describe what you already tested.

  • Share The Picture Test Result — Say whether the line appears during the internal picture test.
  • Name The Line Type — Vertical line, horizontal line, one line, or multiple lines.
  • Provide The Model Code — It’s usually on the back label and in Settings, then About This TV.

What Usually Makes Repair Worth It

  • TV Is Under Warranty — If it’s in the warranty window, start with a claim and avoid paid parts.
  • Higher-End Panels With Recent Purchase — Pricier screens can be costly to replace, but warranty terms or discounted parts can change the math.
  • Single Board Replacement — If a technician confirms a board issue instead of a panel fault, repair cost can be reasonable.

What Often Pushes You Toward Replacement

  • Panel Replacement Quote — Panel swaps are often close to the price of a new set in many markets.
  • Older Entry-Level TV — Parts availability can be limited, and labor can exceed the TV’s current value.
  • Physical Damage Signs — Any crack, liquid mark, or pressure bruise points to a panel issue that rarely pays to fix.

Keep The Lines From Coming Back

If your issue was cable or source related, a little setup hygiene can cut repeat glitches.

Make Your Connections More Stable

  • Use A Shorter HDMI Run — Long, thin cables are more prone to signal dropouts that can show as artifacts.
  • Avoid Sharp Cable Bends — Tight bends near the connector can stress pins over time.
  • Seat Cables Fully — A half-seated HDMI plug can work for weeks, then start throwing lines.

Reduce Video Mode Surprises

  • Keep Auto Resolution On — Let the device pick a standard mode unless you have a reason to force one.
  • Update Consoles And Sticks — Source firmware updates can fix HDMI handshake bugs.
  • Restart After Big Setting Changes — After changing VRR, HDR, or refresh rate, restart both devices.

One-Page Checklist You Can Follow In Order

  1. Check The Menu Overlay — If the line is on the menu, treat it as a TV-side issue.
  2. Switch Inputs And Apps — If it only happens on one device, stick to cables and that device.
  3. Swap HDMI Cable And Port — Rule out the simplest failure first.
  4. Power Reset The TV — Unplug, hold the TV power button, wait, then retest.
  5. Run The Picture Test — If the line shows in the test, plan service.
  6. Reset Picture Settings — Clear picture-mode glitches without wiping your TV.
  7. Document With Photos — Capture the line on menu and test screens before calling for service.

If you work through the steps above, you’ll end up with a clean answer: fixable with a cable or settings change, or a hardware fault that needs service. Either way, you won’t be guessing.