sony tv kv-ar25 m86 problem

hi i have a tv sony kv-ar25 m86
i have a problem, all the input video and the RF input are black and whit( input video1 and input video2 and input video3 and input antenne ) the picture black and white, only the input RGB colored i connected dvd on the input RGB the picture with colors
somebody tell to me : the problem in the board pal secam ntsc
i need your help thanks

georgeschalhoub