Hi. I own a 1995 Plymouth grand voyager, and originally it had the infinity sound system, But when I turned on the radio, it'd make a click and a low humming noise from one of the rear speakers, and when I got it to play a tape, it would only play out of the rearmost left speaker. Along with that, the radio of the head-unit didn't work, (Infinity III head unit). So, I tossed that one, and put in the "basic chrysler" radio out of an old jeep, It worked out of the rear speaker, but it only had the lower end of the audio. Rigged up some new speakers in the dashboard (Which appear to be speaker-level outputs) and those work pretty well. But if I tried connecting a speaker to any of the four-pin connectors in the door speakers or the rear-hatch speakers, it's a really low signal, and i'm assuming the black boxes on the OEM speakers (nonworking) are amplifiers. I'm just trying to figure out how i can go about replacing these, under the condition that the amplifiers built onto the speakers, are all broken except for the one partly-working one on the rear door. (I'd like to keep the original tape deck if possible, or if i have to go aftermarket i'll get one of those retrosound radios, because I'd really like to keep the oem look of the van, and I feel putting in a flashy aftermarket radio or a touchscreen radio would mess that up)

Thank you, If y'all need any pictures of the connectors, or the van in general, please let me know and i'll get those to you as soon as I can.

 

look up those oem pre 95 infinity - used replacement speakers on fleabay.
i had the same issues with a door speaker.
install the replacement speaker, and your done.
you can also try re-sordering all the wire points on the speakers too.
g/l