Originally Posted by Warlock III
The infinity has a factory installed amplifier, and 4 wires running to the speakers.
If I recall, the entire system is dependent on the factory amp. That usually means that it's an all or nothing scenario. However since you have bass it sounds as if you have at least power going to the amp. I'd start by checking all of the connections especially behind the head unit. It almost sounds as though the PO wired the speakers independently and the tweets directly to the unit.
However, it does sound as though it's just a blown speaker.
I said screw it and reassembled everything and the woofer on the passenger door is producing sound yet no sound out the tweeter still, also sounds like the Infinity Amp is still functional since when you plug the harness for the stereo in, you hear a tick in the dash and the speakers burp.