Samsung PL64E8000GFXZP - Manual (Page 565)

properly, you may be having a cable
issue. If you have a cable or satellite
box, your TV may appear to be off
because the cable or satellite box is not
outputting a signal. To test the signal
output of your cable or satellite box,
press the guide or info button on the
cable or satellite box remote control. If
the screen displays the guide or info
data, the problem is caused by the box.
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