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Step 1
Cycle through the TV's video inputs to verify that your TV is set to the right one. For instance, if you are attempting to use a digital cable converter box that is plugged into the Video 1 input and the TV is set to a Video 2 input that has nothing plugged into it, the TV will not display any picture or sound and may even say "No signal" on the screen. To cycle through the inputs, use the input selection button, typically labeled "input," "source," "TV/video" or the like.

Step 2
Reseat the video and audio input connections to verify that a loose cable is not causing the TV's loss of signal. If you have a coaxial cable connected from your wall cable jack directly into the TV, it may have come loose thereby eliminating all picture and sound on the TV. Locate the connection cable or cables of whatever device you are attempting to watch and unplug/replug them from where they plug into the TV.

Step 3
If the above does not solve, look in your manual for instructions for a hard reset.

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If the problem persists (or if you require further explanation), you'll have to obtain a walk-through from Sharp: use the contact information at https://www.contacthelp.com/sharp/customer-service.

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