For some reason my push button on my dash isn't lighting up... Does anyone else have the same issue??

 

Mine doesn't light up either. I don't remember it ever doing so.
I believe it only lights up when the battery in the FOB is weak, and you get a message in the MID to hold the FOB next to the Engine Start button in order to get the car running in that situation.

 

Mine does light up that I've noticed.

 

Mine lights up at night.

 

It is lit at night, after opening the door at night, and when you touch it lightly after the courtesy lights have gone off.

 

The lettering on my button (ENGINE START/STOP) does illuminate at night for me.
I thought the OP was referring to the green LED at the top of the button.
(By the way, my green LED does illuminate if I press the button without first touching the brake pedal, to put the car in accessory mode.)