Two hours ago my son had the system working and was watching tv. We shut the system down to run an errand and when we came home turning the system back on, there is no video output. Not from the cable box,or the dvd. Audio comes through fine.
Where do I begin to troubleshoot this one.

Well I'm adding this note since I somehow through a power cycle and reset and a few prayers and swears regarding the oldest part of the system (the tv) its working again. Weird.