Why does the radio light stay on when the vehicle is shut off?

Sounds like it may be the memory wire to the stereo which keeps fire to stereo,meaning hold settings for clock and station settings,you may have to remove this wire to kill total fire to stereo,it will be a yellow wire.

Thanks...I'll give it a try

I have a 2013 grand Vitara and the screen is blank and the radio won’t turn off from the manual button or the steering wheel and I can’t turn it down or make phone calls etc can you suggest what may be wrong thanks