How to Fix Onn Roku TV Horizontal Lines On Screen?

If you’re facing the well-known onn Roku TV horizontal lines on screen, we have a solution!

The horizontal lines emerging from your TV’s side frames can be a result of a power problem, loose connections, or a failure of the gate drivers.

We recommend the following steps to fix the horizontal lines:

There is much more to discuss, so proceed with the comprehensive guide!

How to Fix the Onn Roku TV Horizontal Lines On Screen?

Note: Have you checked if changing the Roku channels affects the horizontal lines?

1. System Restart the Onn Roku TV

The system restart is a quick way to address underlying issues with the onn Roku TV, through the interface menu.

All you need is the television remote control to access the TV’s settings and initiate the system restart while the device is turned on.

Follow these steps to remotely system restart the Onn Roku TV:

1. Press the “Home” button on the onn Roku remote.
2. Navigate to “Settings” and access the “System” tab.
3. Next, select “Power” and highlight “System Restart.”
4. Wait until the onn TV powers off and reboots by itself.

Important: Unplug the Onn Roku TV!

Suspending the TV’s power supply is an additional method to address the horizontal lines issue.

Disconnect the TV’s power cord from the outlet and wait for a minimum of 60 seconds until all of the power has drained.

Then, reconnect your TV’s power cord and check if the issue persists. 

2. Check the TV’s Cable Connections

The next leading cause of the horizontal lines on your onn Roku TV is faulty or loose cable connections.

All third-party devices connected to your TV over HDMI, Optical, or any type of audio cable could degrade the video broadcast signal and cause playback inconsistencies.

So, we recommend the following:

• Inspect the HDMI cable: Verify all video cables connected to the back of your TV and external device are secured on both ends.
• Switch the HDMI ports: Connect the external devices to a different port on your onn Roku TV and test.
• Connect another device: Use another external device compatible with the same cable types to determine if the horizontal lines are still there.

Important: Test the Roku On Another Source!

If possible, it’s advised to cycle through your onn Roku TV’s sources and determine whether the horizontal lines occur on all broadcasts.

This way you will determine whether the fault is caused by the TV itself or one of the connected devices.

Tip: It’s also recommended to temporarily disconnect all third-party devices from the TV!

3. Update the TV’s Software Version

In some cases, the Onn Roku TV horizontal lines on screen can be caused by an outdated version of the firmware.

Hence, the next step is to verify that the TV has established a secure internet connection and upload the latest operating system build available in the system menu.

Here’s how to update the Onn Roku TV:

1. Press the “Home” button on the onn Roku remote.
2. Scroll and enter the “Settings” tab then “System.”
3. Choose “Software Update” and press “Check Now.”
4. Wait until the TV finishes the automatic update check.
5. Follow the instructions to update your TV’s OS version.

If your TV has established a successful connection to the internet, all newer OS versions will be validated automatically, and you will be able to begin the update. 

Note: Do not interact with the TV or press any buttons on the remote control during the update!

4. Squeeze the TV’s Gate Drivers

While this is an unconventional solution, it had great success for users struggling with horizontal and even vertical lines on their onn Roku TV screen. 

All you have to do is gently squeeze the exact section from the TV’s side panel from where the horizontal line emerges from. 

For example, if a horizontal line is shown in the upper part of the screen, use your index finger and thumb to squeeze the panel from both sides and apply a little force if necessary. 

The gate driver is laid within the side, upper, and rear frame of the TV, meaning squeezing the screen instead won’t do anything.

Repeat the squeezing in intervals of 2–3 seconds and then reboot the TV to relaunch the gate drivers. 

Warning: Applying too much force and lead to display damage!

5. Factory Reset the Roku TV System

The factory reset can be extremely helpful for the onn Roku TV lines on screen, especially if the problem is software-related.

After ruling out surface-level hardware issues with your TV, a clean system reset should be a step toward fixing or at least identifying the TV display problem.

Follow these instructions to factory reset the Onn Roku TV:

1. Press “Home” on the Roku TV’s remote control.
2. Go to “Settings” and access the “System” menu.
3. Select “Advanced system settings” on the page.
4. Choose “Factory reset everything” from the tab.
5. Enter the four-digit code that will appear below.
6. Proceed with the steps to factory reset the TV unit.

Reminder: Once the factory reset is successful, you will be brought back to the TV’s initial setup screen and prompted to re-apply all essential system settings.

6. Inspect the Timing Control Board (T-Con Board)

The timing control board of any onn TV takes the individual frames generated by the GPU and corrects their color and brightness before sending them out to each driver. 

If there’s a fault with the transmission of correctly-themed pixels between the t-con board and the gate drivers, there’s a persistent chance for horizontal lines to appear on your TV screen.

Alert: Disassembling the onn Roku TV will void the manufacturer’s warranty!

Step #1 Preparation

First, there are several important preparation requirements before interacting with the TV:

• First, disconnect the TV’s power adapter from both ends.
• Acquire a Phillips screwdriver, a pry tool, and a wrist strap.
• Work in a safe environment to prevent damaging the TV.

Once you have all of these, we can proceed with the disassembly steps!

Step #2 TV Disassembly

1. Lay the TV on a flat surface and locate the rear panel screws.
2. Use the screwdriver to uninstall each of the screws on the back.
3. Carefully pry the back panel of the TV to remove it successfully.
4. Lift the rear panel to expose the hardware of the onn Roku TV.

Once the hardware is visible, you should see the main control board, the motherboard, and the t-control board.

So, proceed with the third step to recognize and inspect the control board.

Step #3 T-Con Board Inspection

Once you’ve disassembled the TV, locate the t-control board by searching for the silver-lined ribbon cables attached to the side.

The board is held by two medium-size screws, but do not take it out before inspection.

Damage to the timing control board can be identified by:

• Marks of burning or surface discoloration.
• Loose ribbon cables or HW visual damage.
• Blown, leaking, or bulging board capacitors.

Step #4 T-Con Board Replacement

While replacing the timing control board is relatively easy as it’s only held by two screws, you should still know the exact model of your TV and the exact model of the board.

For that purpose, it is best to consult with a technician or learn more about the condition of your current t-con board, before purchasing a brand-new one.