It is possible to have a switched power wire going into the doors if the vehicle came with the Infinity system. They will have either a remote amplifier under the right rear seat or the door and rear speakers will have small amps bolted to them. Unlike the complicated GM and Ford systems that must be paired with an amp when it is used, all Chrysler radios put out speaker-level output. The amps do not increase volume or power. They only modify the tone response for the shape of the vehicle.
The easiest way to see if you have the Infinity system is to look at the plug on one of the speakers. If it has four wires, it is the Infinity system. If it has two wires, there's either a remote amp or it's not the Infinity system. The Infinity model radios look and work exactly like the non-Infinity models but they put out less bass. The bass is made up in the amps. With those speakers and an aftermarket radio you'll find the sound is more pleasing if you turn the bass down.
There's a few different ways the amp(s) can be powered. Normally if there's four speakers with amps, they are powered through a "speaker relay" or "amp relay". The high-current switched power circuit has its own fuse and that's the one that would blow if you grounded the power wire in the door while the ignition switch and radio were turned on. The radio would still have a display and it would operate normally but the only sound you would get would very tinny. The dash speakers, (I think) would work but only the tweeter part of the rear and door speakers would work.
The other way they can be wired is a single remote amp has its own turn-on circuitry that is triggered by the "switched power" wire from the radio. All aftermarket radios have that wire too. It can also be used to run a power antenna. In this system there is no power wire in the doors for the speakers so you shouldn't be popping any fuses. The amp still has its own fuse. Again, if it was blown the radio would operate but with no sound.
Wednesday, July 4th, 2012 AT 8:03 AM