Walking yourself through some simple troubleshooting tips can help you discover a basic solution before you take your unit in for repair or spend your day on the phone with technical support.
The exact terms and settings may differ depending on the make and model of your television. However, most of the problems that arise and the ways to remedy them are universal.
Keep your TV away from air vents that can expose it overly hot or cold temperatures.
Also keep it away from excessive moisture. If it starts to overheat or if the power indicator starts blinking, turn the TV off, unplug it and plug it into a different outlet.
If you see black bars at the top and bottom of the screen or on the sides, adjust the aspect ratio, either to 4:3 for standard TV or 16:9 for widescreen.
If you turn on the TV but no picture shows, or if the picture looks fuzzy and unclear, first check the connections. See that the cables are connected securely and to the input for the component you wish to view, and have the TV set to that input. Turn the TV to the correct channel, usually 3 or 4. Turn off or move any electrical devices that may cause interference with the picture. Switch between component inputs (cable and DVD, for example) to see if there's a noticeable difference. If so, the problem may be with that component.
HDTVs feature a number of adjustable video settings. They're a good place to start if the picture quality isn't what you want. Use the remote control to access the various menus.
Set the picture resolution to 1080i to get optimal video from HD channels. These settings may differ between standard and HD channels, and between different components (cable/satellite and DVD). The components may have their own settings to adjust as well.
Also use the menu features to adjust the sharpness, brightness and contrast to improve the picture. Some TVs may have other options as well, such as digital noise reduction to cut down on interference.
If you have video but no audio or if the audio is too low, double-check the cable connections. Make sure that "Mute" hasn't been activated, either on the TV or video component you're viewing. Adjust the volume, either manually or with the remote control, on both the TV and video component to see if it changes.
Go into the menu. Different brands of TVs have different audio settings, such as "Mono" and "Stereo," or "Analog" and "Digital." See that audio is on the correct setting and enabled for that particular input. Change the channel or try a different component input---is there a substantial difference?
If the issue or issues persist after you try these steps, your TV may need service. Before you call a professional, consult the owner's manual and visit the TV manufacturer's website support page for more troubleshooting tips. The support page will also provide terms and settings for your specific model, updates, accessories and customer and technical support.