2005 Mazda 6 a/c, rear window, and defrost not lighting up


Just got a 2005 Mazda 6...after I brought it, I noticed that the lights on buttons on the dash board ain't lighting up. What can cause this to happen??? Also the lights that suppose to pop up on screen for a/c, defrost, or air coming in ain't turning on. Can some one help me out???  Thanks and appreciate it.