Dashboard Not Illuminating

[Tysiin02]

Hello,

I have a 2002 GMC Denali and I'm experiencing billions of problems. My dashboard will not light up at night on its own. If I turn the key to acc at night it will turn on the radio and clock, But when I start the car the radio and clock turns off. Addition to all this the dashboard doesnt light up in the day or night. I changed the headlight switch 3 times and check all fuses. Still no luck.. Have anyone experience a problem such as mine? Thanks a million for any info anyone can provide....