LED backlight, panel line, or motherboard failure is among the most common causes of this issue.
If the TV has sound but no picture, the issue is often in the LED backlight system, the T-CON board, or the panel circuit. In some cases, the mainboard still sends the signal correctly, so audio remains active while the screen receives no light.
Running the device like this for too long can cause additional damage. A proper diagnosis helps identify the faulty part and makes it possible to repair the LED strip, panel line, or electronic module accurately.