after market cd player worries

[justin31]

hi all,
my 1997 passat SE has a cassette player fitted as standerd and am wanting to change it for a JVc cd player which i have taken out of my old car.

will any of the digital display(climate controll,temp gauge ect..) be effected? the reason i ask is because i used to own a vauxhall corsa and when i took out the original cassette player and replaced it the digital display displaying the tempreture,radio station and clock stopped working and was replaced with just a ---/---.after contacting vauxhall they said that the cassette radio was linked to the display and wouldnt work unless i got a genuine vauxhall cd player(which cost a fortune) or replaced it with the radio cassette player

will have the same problem or is it ok to go ahead and fit it?

thank

justin