07 caravan installed a boss double din Powers on but no sound

That year Caravan and most Chrysler products have outboard amplifiers. The stock radio turns on the amp and sends low level signals to it. Check the new radio, wiring harness and adaptor you may have used. You can bypass the amp, but you have wire to the speakers. The amp is behind the rear passenger side speaker. I think you can pull off the speaker panel and remove the speaker. But not certain you get to the amps wiring. If not, you have to remove the entire rear panel to get at it.