Audio Systems: car radio, fuse block, car radio

Question
i intalled a kenwood head unit and hooked up an amp everything was working then it stopped and radio didnt work so i returned and got it fixed now it still dont work and now my inteior lights will not come on either what should i do.

Answer
Nick,

 it sounds like a fuse problem , go to your fuse block and pull each fuse out one at a time and check for blows .. CHECK ALL FUSES not just radio related ones ... this should cure the problem .. hope this helps you out if you need anything else let me know

thanks