head unit, conversion van, no sound

I'm putting in a deck and overhead in a chevy 2005 conversion van(regency). The deck is going in the rear of the vehicle. I installed the deck first to make sure I can get sound out of the speakers on the celing. Hooked it up only wires going to it were constant, switch, and ground with a set of rcas. The rcas were plugged into the line out on the old unit(smashed up so couldn't test). After I connected I get no sound. There is a switch right next to the radio and I still get no sound no matter what position the switch is in. There are a bunch wires coming from where the mobile video once was(about 6-10 wires, coaxail cable and rca). I looked under the rear seat and there are 2 wireless fm modulators. Can anyone give me any help as to solve this.

Where's the amp?  Sounds like it's not turned on.Support the12volt.com

Thats the strange thing is that there is no amp. The only wires that were connected to the old head unit was constant, switch, and ground. Nothing else. I don't know if there should be another switch somewhere that I'm just missing that lets the rear head unit actually make sound.

There must be an amp.  Speakers need to have an amp driving them or they will not produce sound.  There is either one inside the head unit (in which case the speaker wires will be connected to it) or one located elsewhere in the vehicle.  You mention RCA cables.  These are used to connect the HU to the amp.  Follow those and find out.Support the12volt.com

kassdog wrote: Followed the rca and they ran to one of the two wireless fm modulators under the 3rd row seat. Just for clarafication I'm doing the back headunit, not the front.

Then your system must be setup to send the signal from the back HU to the front one (or to an additional receiver driving an amplifier) via FM.  Is the modulator on?  Is the front HU or receiver on?  Is it properly set to receive the signal?

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We do warranty work on Regency, the rear radio's are headphone ONLY!  The speakers in the ceiling are for the TV, not the radio, the switch behind the driver seat is to turn the TV external sound on and off,,,,if you have any other questions you can call Regency at 1-800-989-4727 BTW,,,the wireless modulators are 49mhz transmitters for headphones, not wireless FM Modulators,one for the TV and one for rear radio,,,

Aha!  There you have it, thank you Ctoh.  Always a good thing to understand your system before you work on it, eh?  Support the12volt.com

Beat me to it Ctoh. I just tore apart one of these a couple weeks ago and started fresh.