re-routing power for amp

[Misuta_Yancha]

so I have a 2001 jetta and I was wondering if anyone else has one that knows where the electrical cables cross the fire wall

 

all help would be greatly appreciated!! thanks in advance

[sYstEmATiC]

well if its for an amplifier, you will need to run your own because the wire you need for an amp is normally quite a bit larger than any wire that crosses the firewall. if you have never done it before, i would strongly advise you let someone who has show you how to run the power and ground wires.

 

what kind of amp do you have?

[Misuta_Yancha]

well if its for an amplifier, you will need to run your own because the wire you need for an amp is normally quite a bit larger than any wire that crosses the firewall. if you have never done it before, i would strongly advise you let someone who has show you how to run the power and ground wires.

 

what kind of amp do you have?

 

I have a JL audio 400w but I already installed it myself... it's just that the power is comming from the head unit

 

the only thing I am changing is that power will come from the battery and not the head unit

[sYstEmATiC]

good thing you didnt leave it the other way or your bound to fry something REAL quick. ok im thinking you are asking where to feed the wire from the battery through the firewall? if this is the case, a lot of cars have rubber grommets that can be drilled through pretty easily near the steering column. if not, just look for a decent spot to feed it through. if you cant find a spot, time to break out the drill and drill your own through the sheet metal. just incase you didnt already know, try to routwe the power wire on the opposite side of the car that you have the rca's ran through. this will prevent you from having that humming sound coming through your speakers.

[Verran]

I have a JL audio 400w but I already installed it myself... it's just that the power is comming from the head unit

 

the only thing I am changing is that power will come from the battery and not the head unit

I'm not sure I know what you mean. You say it's installed with power from the head unit powering the amp? It's working like that? Generally, that's a pretty poor way to wire it, and in most cases I'd be surprised if it worked at all.

 

What you need to do is run your own wire (usually 4-12gauge, depending on the power draw of the amp) from the battery to the trunk (assuming that's where the amp is). Sometimes you can punch through an existing hole in the firewall, but in most newer cars it's become less likely. I had to put my own hole in in my Focus. This can really be done anywhere on the firewall, and it'll depend on the car. You just have to do a bit of scouting on both sides of the firewall and find the place that'll be the easiest to get at without hitting anything else. You should also make sure you use a grommet on the hole through the firewall, and make sure your power wire has an in-line fuse.

 

The wire going from the head unit to the amp is the remote wire, which is a just a signal to tell it when to turn on. It's very low power and cannot power an amp of any size.

[Misuta_Yancha]

The wire going from the head unit to the amp is the remote wire, which is a just a signal to tell it when to turn on. It's very low power and cannot power an amp of any size.

 

oh god no that's not how it's ran... I have a split on the power going to the head unit and it's been hooked up that way for about 3 months with no problems other than when the volume is up the amp causes ALL of the lights in or on the car to dim when the sub hits including the headlights

[Verran]

oh god no that's not how it's ran... I have a split on the power going to the head unit and it's been hooked up that way for about 3 months with no problems other than when the volume is up the amp causes ALL of the lights in or on the car to dim when the sub hits including the headlights

LOL! That's good. I was really hoping you were smarter than that, but your replies haven't been overly descriptive, so it's kinda hard to tell.

 

What size wire are you planning to run for the amp? If it's been running off the head unit power wire for months, then I'd say you shouldn't need more than 10 or 12 gauge wire. Something of that size is usually small enough to "share" a factory grommet with something else. I did that in my old Dakota. Just find an existing grommeted hole that looks like it could have room for another wire. Then either just push it through the existing hole, or do what I did (which is less graceful ), and use a knife to open the grommet up a bit and make room for the new wire.

 

That's all dependent on your car though. Every car's different and that may not be possible in yours. Just whatever you do, make sure you run an in-line fuse. I've seen so many people that don't, and it's just -asking- for a fire to start in your trunk.

[gotdamojo06]

What you need to do is take the Remote wire coming out of the Head Unit (Usually a blueish color) and plug that into the "REM" port on the Amp. Take the ground wire (I use 4G.) and mount that to the side panel of your car, using self tappers and a o-ring. Run the power wire from the interior toward the drivers side under dash. Pull back the carpet and you should see a rubber boot (big clump of rubber like a cork in a wine bottle) you can either cut through it or you can lift part of the rubber boot up and run the wire through (thats how I always do it). Then you take your inline fuse holder and take the fuse out and connect the wires to the amp and the battery. Once all wires are plugged in (Speaker wires, RCA cables, Remote wire, +12V *power*, and ground wire) then you can put the fuse back into the fuse holder.

 

All the Remote wire is, is a power signal that goes into the amp signaling that it needs to be turned on, you could actually hook it up to the batter with a switch in it so the amp can be shut off...

 

hope this helped...

[Misuta_Yancha]

LOL! That's good. I was really hoping you were smarter than that, but your replies haven't been overly descriptive, so it's kinda hard to tell.

 

What size wire are you planning to run for the amp? If it's been running off the head unit power wire for months, then I'd say you shouldn't need more than 10 or 12 gauge wire. Something of that size is usually small enough to "share" a factory grommet with something else. I did that in my old Dakota. Just find an existing grommeted hole that looks like it could have room for another wire. Then either just push it through the existing hole, or do what I did (which is less graceful ), and use a knife to open the grommet up a bit and make room for the new wire.

 

That's all dependent on your car though. Every car's different and that may not be possible in yours. Just whatever you do, make sure you run an in-line fuse. I've seen so many people that don't, and it's just -asking- for a fire to start in your trunk.

 

I am going to run 8 guage so that I can add more amps in the future for the rest of my speakers and possibly a car computer in the sort of distant future

 

and I also spent about 35 minutes looking for the hole in my firewall but couldn't find it... however I think I know of a good spot to put one if necessary, but I would rather just try and rout it through the one already there

[gotdamojo06]

if you are going to run 1000-3000W then you should probably go with 4G. thats what the "standard" is you could go with 0G. however that can be expensive and a pain in the arse.

[Verran]

you could actually hook it up to the batter with a switch in it so the amp can be shut off...

I actually put a switch in my remote line in my first car. I called it my "cop switch". It was my bass insta-kill button. I also used it to disable the subs whenever my parents were going to drive the car.

 

if you are going to run 1000-3000W then you should probably go with 4G.

He's only running 400W. I think 4G is a bit much, and it'll be much harder to get through the car.

 

you could go with 0G. however that can be expensive and a pain in the arse.

0G?!? That's bigger than a freakin' garden hose! That's definitely overkill.

[gotdamojo06]

I have been debating about putting one on mine, however my Kenwood Head Unit has an built in option to turn the woofers off...I do however install the switches in any cars that I work on that are running off of the stock radios, that way they have control over the woofers.