help with sub setup

[cdiroms978]

hey guys
my buddy and i just installed an aftermarket amp/box/subs in my bonne and we've been having problems with getting the subs to fire. the setup works in his volvo, but just doesnt work in my car for some reason. all of the wires have current, the ground is good, the remote wire is fine because the light on my amp is on but the subs just dont seem to want to work. i tried it on my Dual XDVD 1170 and it didnt work so i switched it out with a dual xdma 450 with the hope the connectors would be the same for the wiring harness. they werent, so after my buddy rewired everything for the new head unit we plugged in the rca's and still nothing from the subs. its baffling to him and his dad, who have been working on cars for years. Could it be that i got two dual headunits that had bad RCA outputs? or am i looking at a bigger problem here.

Thanks in advance,
Christian

[swampthing]

First thing I would do is plug an audio source directly into the amp (low volume of course) and then see if the amp makes sound.

If it does you know the problem is either the head unit or the cable.

If it doesn't its the amp or associated wiring

[cdiroms978]

its not the amp because we plugged the subs back into the car it came out of and they fired right up no problem. we've also tried two different RCA cables, so i dont think its the cable. so that leaves the head unit, which i admit is kind of a piece of crap, but it just boggles my mind that TWO different head units' sub outs are a bust.... but since theyre both dual i guess it wouldnt be out of the question?

[cdiroms978]

im pretty sure i also have an amp that came with the stock system, i found the ground wire for it under my backseat and the wire seems to go up under the dash. would that have any effect on the amp for the subs not powering them?

[Jfridge92]

I don't mean to sound insulting at all when I say this, just making sure the simplest things are covered first lol (Because aren't they always the easiest to overlook) but on my stereo, you have to manually turn the sub outputs on in the menu. Is yours similar and do you have it sending signal to the RCA's? It took me forever to figure out that I had to actually turn the RCA's on and that they didn't just come on automatically.

[cdiroms978]

yes, the sub outs on the stereo itself are turned on

[cdiroms978]

Basically everything is wired correctly, the sub outs are turned on, everything SHOULD work, but it doesnt. After a lot of troubleshooting my buddy and his dad came to the conclusion that its the RCA's on the headunit

[cdiroms978]

i just plugged in an RCA to 3.5mm and tried playing music- still not a sound. i could take this EXACT setup with the wiring just the way it is and put in my buddys car and it would work perfectly fine. Im thinking that the battery is only putting enough power out to turn the amp on, but not power the subs. what do you guys think?

[swampthing]

Then it has to be the power, ground or remote. Where is everything wired?

[cdiroms978]

the power is hooked up to the positive of the battery terminal, the ground is grounded with the battery ground under the back seat, and the remote it with the two blue wires behind the HU

[Zeik75]

You could try giving the ground its own spot on the car. Maybe its connection just isn't good enough?

[cdiroms978]

I've tried 3 different grounds with no results. I'm bringing my car in to a local car audio shop on Friday so they can fix this because I'm at a loss as to what the issue is. Ill keep you all updated

[cdiroms978]

turns out it was a bad fuse in the aftermarket amp wiring kit i bought.... thank you for all the help anyway guys i appreciate it!