I just got a new head unit, wiring harness, antenna adapter, and dash mount. I wired it all up so the colors match. plugged it in, annnnnnd.... Nothing. So I figured it was one of the wires... I must have connected one wrong... Nope. I plug it back in after triple checking. Nothing. I check radio fuse. It is fine. I cant figure it out
please help

 

Did you ever get an answer on this? Chances are that you don't have a switch wire (Red maybe?) in your factory harness. You have to find a switched 12V source to hook it to. The yellow wire actually powers the radio and is always hot (to save stations, etc) but the red wire is what tells the radio if you have turned the ignition on. You can check by hooking the switched wire to the yellow wire (Both the red and yellow attached to yellow) and see if the radio comes on. This is based on standard colors so make sure and check your diagram to make sure you don't fry anything.