The Vizio TV displays a yellow light but the screen remains black, likely due to damage from a lightning strike affecting the main board. The power supply appears functional since the yellow light is on, indicating it is communicating with the main board. If there are no visible signs of damage or burnt smells, the main board may need replacement. Unplugging the TV for an hour may help reset any overcharged capacitors. Lightning can cause electrical surges that damage appliances, and it's crucial to use surge protectors to prevent such issues. If the TV is not repairable, selling it for parts may be a viable option.