Ok So I bought a Dodge ram 1500 4x4 with the Infinity Sound System .Someone has apparently replaced the two door speakers with a PowerBass Brand 6x9s . The System Sounds Like a combination of distortion /and or sound of a blown speaker. Neither of rear door speakers work but have original infinity speakers there still. Checked wires by plugging in new fosgate replacements speakers and still no sound from rear doors. Also took a New speaker and Hooked to front passenger door and still sound didn't change Sounds like Distortion /interference or something, I also replaced the stereo head with another original one to see if it changed which it did not the interior dash wiring has not been tampered with still wrapped tight factory. Im confused on what happened or how to fix.

 

I don't think the system changed much for the third gen trucks...... So, the old trucks had amps AT the speakers. Simply replacing the speakers is inadequate to the task, unless they also have amps built onto them?

 

When I had my 02 with Infinity the Amp was under the dash