Infinity stereo problems

I am trying to replace ,with a new radio,dvd but when connected there is no sound,the old stereo was intermitent;have replaced front speakers with new infinity's, is there a fuse in the system ? other than by the drivers panel. Can find no amp,if it needs one, Wiring has been tested system works but can get no sound out of the car speakers

I am having a similar problem w/my 96 sebring. my headunit seems to working fine but no sound through the infinity speakers-amp. I assume there is a separate fuse for the amp but cannot find it. I have been searching for help but keep getting directed to the dealer. Hopefully someone will reply with better news!

how about some more detail on what kinda cars u guys are working on personaly as a chrysler tech from what u are telling me on here u cant even tell u what to look for more info is needed its like asking what color is this to a blind man.