97, no power to speakers,please help!

i have a 97 ranger. my head unit is recieving full power. my speakers DO WORK ( as in they are not blown), but they are not recieving any power. everything from the head unit IS wired correctly. so i do know that is not the problem. the wire harnesses on the truck are also functioning correctly because i tested them with an outside source speaker. i also checked all of the obvious fuses. so i'm asking for ANY help possible if there is some sort of fuse or relay somewhere on the truck that could be causing this, or anything else for that matter. thank you in advance.

you tested them with an outside source speaker? are you saying you hooked up the deck to other speakers and it worked? if so, then it is your speakers for sure. check the independence on the speakers. most head units only handle 4 ohm speakers.