I had a problem using the rem line outs from the head unit and the door speaker amps so i ran a wire from one of the key'd on fuses to the amp. Here this picture might clear things up. One thing, on this image it shows the REM line on the amp as the one of the end lugs on the amp... Some amps have the REM lug in between the 12v and ground so make sure you verify how each lug is marked.
