remote only turns tv unit on/off

Hi all, have JC Penny color tv/vcr combo unit produce in 1994. Had been watching a dvd disc and all was well. Could take the remote control and switch between the dvd playing and watching tv or watching a recorded video cass or tape a show on a vcr tape. for sNow for some reason, I can only get the connected dvd unit to work. Now, when I attempt to use the remote that used to control the tv and switch via that remote to tv/catv/ it seems that every button on the remote only turn the tv on or off. As I said I can still use the dvd player but that is all. Oh I can play a vcr tape also, but of course cannot not record anything new. cannot get back into the tv programs. Any help is appreciated. thanks