Passing wires through the firewall
#1
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Year: 1994 SE
Model: Cherokee
Engine: 4.0
Passing wires through the firewall
So...done this more than a few times on other vehicles. Don't see an easy way on my XJ, feel like a dunce. Help this perpetual noob.
I have one amp power wire (8awg) and two wire harnesses with connectors (3/4" by 1/2") that I need to pass through on the passenger side. Can't find any existing spots to tap into. Figured I'd double check with y'all before making a new hole, maybe I'm missing something? If absolutely needed, I could always cut the connectors off and splice the wires together once they are passed.
Ideas, suggestions?
I have one amp power wire (8awg) and two wire harnesses with connectors (3/4" by 1/2") that I need to pass through on the passenger side. Can't find any existing spots to tap into. Figured I'd double check with y'all before making a new hole, maybe I'm missing something? If absolutely needed, I could always cut the connectors off and splice the wires together once they are passed.
Ideas, suggestions?
#2
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Year: 1993
Model: Cherokee (XJ)
Engine: 2.5L MFI
Don't know of any good spots big enough to pass that through. If you are OK with re-soldering or re-crimping the wires, you could go with the firewall pass through that screws down onto the wires to make it waterproof.
#3
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Year: 1999
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I've passed all of my wires through a grommet on the driver's side that dumps them out up above the pedals. You'll most likely have to cut the connectors off.
#4
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its a huge grommet...there for the 5 speed vehicles...iirc, silver dollar size...the wires fit thru that, rtv up any hole you have.
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Year: 1998 Classic (I'll get it running soon....) and 02 Grand
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What in the world is a "one amp power wire (8awg)"?
I'm pretty sure you can run a lot more than 1 amp through an 8 AWG wire.
I'm pretty sure you can run a lot more than 1 amp through an 8 AWG wire.
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#6
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Year: 1994 SE
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Funny thing about the interwebz...hard to tell when someone is joking sometimes. Just to clarify...I have an audio amplifier power wire, 8 gauge...
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#8
No, I don't lick fish.
I myself would personally stick with the gang of wires that runs through at the driver's side though - which is where I also ran mine.
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If you are running 8 AWG to power your amp, I strongly recommend that you run a ground wire of the same size to the battery terminal. Body grounds really aren't very good for large current loads. Without a dedicated ground wire, you are sharing the existing body ground with all the other electrical loads in the vehicle, and take at look at where and how it's attached to the battery. It's not exactly a great grounding point for an amplifier. No matter how good a grounding job you do at the amplifier, you are still going back to the battery via an inadequate grounding point.
If you are concerned about voltage drop by running the power the extra distance to the driver's side, you can always increase the size to compensate. What's the power output of your amplifier, and where are you planning to mount it?
What are you using to fuse the power?
#10
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Funny thing about English. When you say, "one amp" and you are talking about power conductors, the usual meaning is amperes, not amplifier. If you are running 8 AWG to power your amp, I strongly recommend that you run a ground wire of the same size to the battery terminal. Body grounds really aren't very good for large current loads. Without a dedicated ground wire, you are sharing the existing body ground with all the other electrical loads in the vehicle, and take at look at where and how it's attached to the battery. It's not exactly a great grounding point for an amplifier. No matter how good a grounding job you do at the amplifier, you are still going back to the battery via an inadequate grounding point. If you are concerned about voltage drop by running the power the extra distance to the driver's side, you can always increase the size to compensate. What's the power output of your amplifier, and where are you planning to mount it? What are you using to fuse the power?
#11
Never, ever, run a high-draw device (amp, fan, E-brakes...etc...) off the chassis.
NEVER.
Always to the source.
Equal size wire.
#12
To answer the OP-
Pull down carpet from pass side firewall.
Drill 1/8" hole in the clear (both sides) high on the foot well from INSIDE out.
Use 1" hole saw (mini holesaw) to cut a hole for wires.........using your 1/8 pilot hole.
Get 1" grommet, slice from center out.
Run wires through hole.
Slide grommet over wires, insert grommet in hole.
Done.
Pull down carpet from pass side firewall.
Drill 1/8" hole in the clear (both sides) high on the foot well from INSIDE out.
Use 1" hole saw (mini holesaw) to cut a hole for wires.........using your 1/8 pilot hole.
Get 1" grommet, slice from center out.
Run wires through hole.
Slide grommet over wires, insert grommet in hole.
Done.
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Well, I guess you have never talked to a pro, then.
(There are a lot of idiots working in car audio shops. They are not pros. Actually, most of them are not.)
#14
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Year: 1994 SE
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Funny thing about English. When you say, "one amp" and you are talking about power conductors, the usual meaning is amperes, not amplifier.
If you are running 8 AWG to power your amp, I strongly recommend that you run a ground wire of the same size to the battery terminal...
If you are running 8 AWG to power your amp, I strongly recommend that you run a ground wire of the same size to the battery terminal...
http://www.crutchfield.com/S-n6Y3M0t...ion_guide.html
http://www.rockfordfosgate.com/suppo...er/std_alp.php
With these two sources, I didn't think it was needed to search further.
To answer the OP-
Pull down carpet from pass side firewall.
Drill 1/8" hole in the clear (both sides) high on the foot well from INSIDE out.
Use 1" hole saw (mini holesaw) to cut a hole for wires.........using your 1/8 pilot hole.
Get 1" grommet, slice from center out.
Run wires through hole.
Slide grommet over wires, insert grommet in hole.
Done.
Pull down carpet from pass side firewall.
Drill 1/8" hole in the clear (both sides) high on the foot well from INSIDE out.
Use 1" hole saw (mini holesaw) to cut a hole for wires.........using your 1/8 pilot hole.
Get 1" grommet, slice from center out.
Run wires through hole.
Slide grommet over wires, insert grommet in hole.
Done.
If it's any consolation, I have been kicking around the idea of getting one of these sets of beefy battery/ground cables that are all the rage here.
And...back on topic...I am not running a wire from the front right, full left to the driver side, full right again to run down the passenger side, even with a bigger wire to compensate for lost draw. That is counterproductive. I do appreciate the I put though.
Edit: the RF link doesn't seem to be working, here's a screenshot from my phone; best I can do right now...
Last edited by jay_sco; 07-09-2016 at 06:21 PM.
#15
The above pic-
Just above where you are considering coming through the fire wall.
When I wire my amp I will do as you are doing......however......regarding your post from Crutchfield...etc......RF interference.
I will bring amp pos cable to to the pos post on the small fuse block, neg wire will go to the neg post to the left, straight from the battery.
I have no concern for RF interference as I no longer use FM radio, streaming media is not effected by RF noise.
Wiring here is for all my accessories, light bars, e-brakes, trailer accessories, e-fan, ...etc....
I know where my grounds are.
I had a so-called pro wire the sound system in my last truck. He grounded amp to chassis and I had to clean ground several times....nothing by problems and will never again ground to chassis.
Last edited by Jeep Driver; 07-09-2016 at 08:48 PM.