Sound but no picture?
Answer:
check the video cable on the back of the dvd. If your getting picture on your dvd but not on your tv/cable, its possible the cable came lose from either the source (cable/sat box) or the back of the TV. It sounds like a simple solution and is probably the case. Also, if thats not the problem, try changing out the video cable. Cables go bad too.
Before this drives you to drinking, and after you try all the other suggestions give this a try.
Go direct. Take the cable box and the DVD and anything else you have plugged into the TV. Now you are down to the bare set. If you have a picture now start adding items one at a time. It may take some time but it is almost certain to get results. As soon as you loose the picture you have found the problem.
My family TV is way to smart for its own good. One of my kids is on standby at all times to put the mess back together when I hit a wrong button.
Good luck, I know I get frustrated sometimes bad enough that it would make the Pope cuss.
some pretty good ideas but I want to add my little gloom and doom possibility. Often the sets have seperate circuit boards for the coaxial hookup, the componet, composit, DVI, and HDMI. I have seen a pic. lost on a set and then use a different input for the signal (much like you are doing with the DVD) and have a picture. So if you have a way to try different inputs from the same source you can check out this possibility.
use the coaxial input from your cable box to the tv, Pic or no Pic? then change to another input from the same cable box. most have HDMI or DVI or componet as well as the coaxial. try the others PIC or NO Pic.
If you find you have pic from one and not the other then you could have a bad circuit board. off to repair shop. If one works and you still have a way to view the cable and a way to view the DVD then don't worry about a repair until you have too.
You did not mention how it is connected now, if you were using componet, composit, or DVI you could have lost a cable as suggest by other answers.
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