What Could Cause a TV Screen to Start Flickering Like a Strobe Light?by Andrew Aarons
Your television isn’t going to work perfectly forever. Over time, the parts inside a TV set slowly wear out, and although a TV should last at least the length of its warranty (or, with luck, much longer), it’s not impossible for a TV to exhibit strange behavior, like flickering and flashing like a strobe light. Unless you intend to run a dance club in your living room, this behavior is not acceptable.
To determine what might be causing your television to flicker, you have to look at everything that connects to it. If the flickering or strobe light effect is only occurring in relation to a single source such as a video game console, DVD player or cable box, then your TV might not have a problem at all; instead, the source is likely the problem. Each video source, whether it be a PC or a set-top box, has its own video outputs that can wear out and break over time, causing the picture on your screen to flicker or otherwise become distorted. Try turning to different channels and unplugging devices from the TV to see whether the flickering is from one of the devices or the TV itself.
If the TV’s power supply was interrupted (during a storm, for example), the power flow to the bulbs in the television may be causing the screen to flicker. If this behavior is happening consistently, whether or not any other video sources are connected to the TV, the power supply is probably causing the problem. Without a steady current, the TV with flicker and flash, creating that home disco effect.
Like any electrical device, televisions need their power circuits cycled -- or cleared -- from time to time. Static electricity or electrical loops cause strange behavior in electronics, but cycling power almost always helps or, at the very least, is an important troubleshooting step. Unplug the TV from any power supplies and then press and hold the power button for a few seconds. Let the TV sit for a minute or two, then plug it back in.
If the TV doesn’t work properly after cycling the power, the issue is almost certainly with the bulb, backlight or LED inside the TV. If these light-producing units stop working properly, they may begin to flicker. Think of a florescent light that’s on the fritz: it begins flickering and flashing before it burns out completely. Contact the TV's manufacturer (especially if your TV is still under warranty) to determine if your television can be replaced.