Navigation screen wont power on/ steering wheel buttons

[crudhunch]

I have an 03 Infinity I35 fuly loaded. All of my buttons work except for my steering wheel. The navigation screen comes out of the dash but does not turn on. I can hear the cd reading when i start the car. How do i get my screen to turn on and how can i get my steering wheel buttons to work. I love cruise control! I have tried looking for the preasure button under the screen but i cant see it. Any help I get would be awesome!