hello, new to forum. had a 2005 crew cab for a while and finally swapping radios. when i hook up the new deck i can get power and the deck works with an external speaker but when i use the speaker wires in the factory harness i get no sound. Did any version of 2005 every have a separate amp that was not integrated to the deck? It seems that the wires must not go directly to the speakers, but instead to an amp first. The factory system is a cd with door tweeters if that helps. can't find any other info on here except the common stuff regarding getting a switched 12volt lead to the new deck.