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Im looking to install a custom built subwoofer box in my car, but I have some questions about doing this. Any help? Answered

I have quite a few questions seeing as how this is my first audio system for cars.

1. The amplifier I am useing has an input near the power inputs that reads REM. My guess is that it is the remote wire the acts as a switch for the amp. so where does this "remote wire" originate from? i.e. where do I plug that wire into my fuse box?
2. If the REM wire is a "on-off" switch will I still need the + wire pluged in?
3. If the REM is not a on-off switch will i need a separte toggle switch?
4. This box is custom made and not factory made. therefore is not built to fit my car specifily. How do I keep the box and the amp from sliding around in my trunk with out drilling any holes or any modifications like that?
5. How do I test the whattage of an amp that does not list that specification?
6. How do I get signal from the deck to the trunk if the rear speakers are located in the doors and there is no way to take apart the dashboard?
7. How do I bridge left and right signal together without blowing out my amp or car stereo?
8. In the front doors I notice, when I remove a cover, 2 wires with its own connector at the end the leads into nothing. My guess is this is a tweeter output. After putting a multimeter to this plug, to insure it is not a turn signal output, I notice the multimeter does not pick up any voltage, or any ohm ratings. so how would I measure the impeadence of the stereo using this plug?
9. I notice in the trunk 4 wires with its own plug that have no place to be. I made sure this was not simply an extra brake light out put by removing the interior wall panal from the inside of the trunk lid to find that brake light plug in there. so my guess is that this is a subwoofer output. is it possible for me to use it if it is a sub output? if so how?


REM wire is a positive feed (since the car is negative ground) and comes directly from the stereo deck. The deck outputs 12+v on that wire (yellow if I recall on a chev)...to turn the amp on. It doesn't draw a lot of current, thats for the heavy duty power input lugs. Again, whilever that line is hot, your amp is turned on.

To stop the box from sliding around, put feet on the bottom that grab the bottom of your trunk - diff feet are available, rubber for a metal bottom trunk, or 'tines' for a carpet bottom trunk.

Wattage: look up the unit serial number/model number

You must take apart your dashboard to get access to the back of the deck -- it will have stereo rca connectors which you run a wire to the trunk. The dash does come apart, but you may only need to take small portions of it off to route the wire. Often you route the wire down the side near the floor edge under a piece of trim. Be creative.

If the amp is bridgable, you have R+ R-, and L+ L-. Only good for driving mono at that point...Hook R+ and L- to the speaker, then R- to L+ as a bridge. *******double check this, search, find a diagram******* doing it wrong will blow up your amp.

Don't worry about that connector, if you see nothing while the system is on and playing as voltage, amperage, or resistance -- then its probably disconnected.

No idea...depends on the car.

are you sure the OEM radio has RCA connectors and REM in the rear of the radio?

i did some research and found theat surprisingly it doesnt have them. however I was able to find something that I feel would probably work but im not quite sure
would you tell me if this would work before i order it?
Amplifier Amp Interface Adapter Wiring Wire Harness
it says it fits a 2011 mitsubishi lancer

if you have a 2007-2011 lancer it'll work; but it doesn't give you the power indicator. Worst case you hook that up to ignition power so it just turns the amp on when the car is on.

the decrription says iyt has REM out put. it connects the yellow wire i beleave

So with the REM wire I will still need the v+ plugged into the amp. Yes?

I have a carpeted trunk space. I was thinking something like zip-ties or Velcro. Either way I need it to be a cheep way of doing this.

In the back of the deck. (This deck is stock but I figured that since Mitsubishi offers a model of lancer that has a built in sound system that come with that model that the deck would have the same wire harness and therefore be able to handle an extra output.) in the back of the stock deck there will be actual RCA outputs fir just this application?

the amp that I have has left and right inputs and left and right output with the amp having two channels (L&R) how would I bridge that?

I made need to recheck that plug. As I recall now I couldn't really fit the prongs of the multimeter into the plug. There may be a chance that there just simply wasn't a strong enough connection. If I do get a reading from the plug (weather it be ohms, volts, or amps) would that be the best way to signal the amp?

I want to avoid disassembling the dashboard as much as possible because I am not very experienced with removing such a large and complicated device.

I do have one more question. How do I control the amps volume?

Yes, you must connect power +- as well as the rem wire, rem wire carries almost no current, just a signal.

Velcro will work great

Factory decks rarely have amp outputs - you will probably need to swap the deck for one that does.

*bridging, again, do research, not sure.

Don't use a random wire you found in the door to plug into your amp.

Amp will have a gain knob somewhere on it - often a screw terminal pot. Set it and forget it - it's loudness is based on the deck which changes the output volume.

ok great.
Im testing the amp and frequecy now using a computer power brick with + pluged in and a jumper from + to REM that carries the same current as +

I checked when I got home. there are definatly tweeter outputs that work. the plug in the trunk still gets nothing. it is impossible for me to take the dash apart (well, not impossibe just beyond my skillset.) the problem with this is the way that the radio fits into the dash, I wont be able to use a system from wal mart or something. Mitsubishi had a clever idea of making the owner have to buy the naviradio system by connecting the radio with the air vents on the same piece of plastic. a new naviradio system is about $499 not to mention installation fees. I did some research and found thaty Mitsubishi has models of lancers that have the sound system built in but without naviradio. i cant imagine they wouldnt use similar if not exactly the same wire harness right?

Again, that's something you'll need to research -- specifics about your car/adapter(s) required.

ill probably run a line out from the rear speakers, the use a step down amp and then the bass amp and subwoofer speaker. would that work?