Mr. HKS

i got a big problem. My interior dash lighting doesn't work, same with my parking lights (signals), and my rear lights. This is all the same connection i think. It use to flicker on and off but now its all off and doesn't come on. All the lights should come on when i turn the light switch one click, (two click would be the headlights, but thats ok). But now nothing works....does anybody know whats wrong? Is it the fuse, wiring or what? Somebody please help..i can't drive at night now coz my back lights don't come on...thanks