Before diagnosing complex television issues, it is essential to begin with core troubleshooting steps. A large number of power and performance complaints on LG TVs stem from simple connection problems rather than internal board failures. Confirming the condition of your power and signal connections will help narrow down whether you are dealing with an external issue or a component failure such as an LG power supply board fault.
Start by ensuring the TV’s power cable is seated securely at both the back of your LG television and in the wall outlet. Faulty seating or accidental loosening can interrupt power delivery and prevent startup. Test the outlet with another device to confirm it is active. Review the condition of your HDMI, antenna, and audio cables and make sure each is fully inserted into the correct port. Worn, bent, or frayed connectors can disrupt both audio and video signals and may appear as power loss, no display, or intermittent operation. If you are using Wi-Fi, verify that the network name and password are correct and that your router is functioning. When using an Ethernet cable, confirm that it is fully engaged at both ends. After confirming the basics, power the television back on and monitor for improvement.
Would you rather watch a video showing an LG power supply replacement? Watch our quick YouTube video below to see how easy it is:
Power Cycle and Reset Steps
Many LG TVs respond well to a full power cycle, especially if the issue is related to standby power or temporary firmware lockups. To perform a proper reset, unplug the TV and wait at least sixty seconds. While unplugged, press and hold the TV’s physical power button for thirty seconds to release stored energy from the power supply. Plug the set back in and test again.
If the display remains inactive or menus cannot be accessed, a factory reset may be required. Refer to your owner’s manual for the reset sequence for your specific LG model. If the screen is blank, a temporary external streaming device may be required to access settings.
Diagnosing LG Backlight Failure
A common symptom of LG backlight failure is a black screen while sound continues to play. A simple diagnostic step is to darken the room and shine a flashlight at an angle toward the screen. If faint images appear, the LED backlight system or LED driver circuitry may have failed. Backlight repair may require replacing the LED strips, LED driver board, or in some cases the power supply board if it is not delivering proper voltage to the system.
Understanding T-Con Board Symptoms
The T-Con board synchronizes panel data and controls image generation. If your LG TV displays distorted images, lines across the screen, frozen images, or no visible picture even when the backlight is functioning, the T-Con board may be involved. Only attempt inspection after unplugging the television and safely removing the rear cover. Look for loose ribbon cables, visible heat damage, or board discoloration. Voltage checks should be performed only if you are comfortable using a multimeter.
TVpartsToday Tip: Use anti-static precautions and safety gear when working inside any television. Components can retain charge even when powered off.
When It Is Time to Seek Professional Support
If after these foundational tests your LG TV still exhibits symptoms such as black screen with sound, no power, flickering, or image distortion, professional assessment may be appropriate. Verify the technician has experience with LG televisions and request an estimate prior to proceeding. Always review whether your television remains under manufacturer warranty before opening or modifying internal components, as this may void remaining coverage.
Frequently Asked Questions
Why is my LG TV playing sound but not showing a picture?
This often points toward a failed backlight system or power delivery issue. Perform the flashlight test and continue diagnostic steps from there.
How do I perform a factory reset on an LG TV?
Navigate to the settings menu, open Support or General depending on the model, and select Reset to Initial Settings. If the picture is not visible, connect a streaming device temporarily to access menu functions.
If during troubleshooting you determine that your LG power supply board, T-Con board, or LED driver may be the source of the failure, our team at TVpartsToday is here to assist. We stock high-quality replacement components, ship quickly, and help ensure you select the correct part number for your exact LG model. If you need guidance identifying the board or validating compatibility, contact us and we will walk you through the process.
Need Help?
If you’re still unsure about the issue or need to replace a part, reach out to TVpartsToday. We can help you identify the exact cause of the problem and provide the right replacement part!
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