# Ground Cable Connection



## ripready (Nov 30, 2013)

In my setup, I have the ground cable connected directly to the ground on my car battery and it runs down one side of the car with the Positive cable. Signal and speaker cables are run together on the other side of the car.

The ground is then split to all the items in the system so there is one common grounding point for all items. 

I've been told that running the ground directly from the battery is best. However, I'm thinking it doesn't matter as long as it's a good solid grounding point on the chassis. The shorter the better.

Opinions?


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## sirbOOm (Jan 24, 2013)

A good chassis/body ground with upgraded ground wire from chassis/body to battery is generally fine. If I were running a wire back to the battery for ground, I'd probably also tap in a chassis ground anyway and let the electrons decide the path of least resistance.


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## ripready (Nov 30, 2013)

Ok if you did that would you have a problem with introducing noise because you have multiple ground points? Or is it technically not considered that since you are splicing into an existing wire?

Now another question would be since it's like a 0 gauge wire for both positive and negative and it runs together down one side (and it's a very long run), is it likely to cause interference or introduce noise? The only precaution I've taken is to run the audio and speaker lines as far away as possible. 

Would additional shielding help at all or is that overkill?


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## PsyCLown (May 17, 2013)

A bit off topic, although still related to it in someway.

The ground in terms of the battery would be the negative, correct?


In terms of the length of the cable run, if it is resistance you are worried about, I do not think it is something to be all that concerned about. The length required before the resistance becomes of any real significance is very, very likely a loooot longer than you would be running.


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## ccapil (Jun 1, 2013)

Yea I agree with sirboom. The electrons will always take the path of least resistance. Jl audio did a study way back, and they used a sniffing device to tell how much of the car chassis the ground (return) took. They tested it on many different cars and found its equivalent to a 4gauge wire. So if you are running high powered amps with 0 gauge power, if you ground to the chassis, it may not be sufficient. It all depends on the car. Some cars have split body chassis and some newer cars have a sound deadening material built into the chassis. Which is non conductive! 
I know of an install with a new model Merc and it had sound deadening material built into it, lucky the installer and me also, knew about this car and looked up the chassis materials etc. So we knew we couldn't ground straight to the chassis, it had to be ran up to the battery. If you have a sniffing device, it will be hugely helpful, or even a google on the chassis. 
In most cases ground directly to the chassis, for 99 percent of installs, this is what I would do other wise it's more install time more $ on wire and it will be the longest distance to take for the return path, when you can ground directly to the chassis at the shortest path from the amp. Then it's up to the electrons to take the shortest path, which may or May not be shorter than if u make your own run of wire.


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## ripready (Nov 30, 2013)

It's a 93 Pathfinder so definitely no issues with sound deadening material. I wouldn't say I'm running high power just 3 amps for a total of about 750watts total. So how do I know if grounding to the chassis is sufficient. What type of problems would I have if it wasn't sufficient?


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## ccapil (Jun 1, 2013)

Usually grounding to the chassis is fine, as long as it's a solid ground. Doesn't move (loose), is to bare sanded metal, is the shortest distance possible from the amp, not 20 inches long, less than 10 is usually good. How many amps are in your system? If u have more than one then u might have to look at a Distro block or grounding to the same place / bolt. As long as the ground is good and measures the least resistance you will be fine.


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## ripready (Nov 30, 2013)

The system has 3 amps in total. Yes I do have a distribution block for the ground so I'm covered there. I recently had some alternator whine introduced into my system after a bunch of changes so I'm just trying to figure things out myself before I bug everyone on the forum. 

Thanks for the info!


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## amalmer71 (Feb 29, 2012)

I don't know specifically about a '93 Pathfinder, but the body panels on modern cars aren't even welded together by more than a couple tack welds then seam sealer is used to fill in the gaps.

I would guess a '93 Pathfinder has a full frame. The best thing to do for a solid ground would go to use the frame to carry the current back to the battery or, as you've done, run a separate wire.

The easiest way to tell is to do a voltage drop on different panels inside the vehicle. With the engine off, run the leads across the battery terminals to get the base voltage (what the battery is currently putting out <- no pun intended ), then run it from the power wire to different points in the vehicle to find the one with the least amount of resistance based on the current drop. Anything more than -0.20 vdc should be avoided if possible.


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## luisc202 (Oct 29, 2013)

I just went through this in my Tundra as the bass hit hard the amp would shut off due to starving from ground. I took out my drill and cl3aned the paint until I could see bare metal and used the bolt for the seat belt and my problem was solved.

IMO running a cable to the negative side of the battery is overkill but maybe I am wrong.


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## cajunner (Apr 13, 2007)

it's expensive to "beat" the chassis ground using a dedicated wire, but it can be done.

is it worth it?

SPL competitors don't think twice, and ess que balks at the additional 1/0 snaking in and around their interiors, bypassing the return path of the automaker and relying on good ol' copper for their amplifier's best efforts...

I think we can all see where I am going with this.

Use the chassis, and as you pick up the alternator whine, and you find voltage differentials from the fuse block in the dash where the deck grounds out, to the trunk you'll listen to the dentist drilling in the background at no particular tooth and say "what did I do wrong?" when all along you knew.


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## steveholt (Feb 25, 2014)

sirbOOm said:


> A good chassis/body ground with upgraded ground wire from chassis/body to battery is generally fine. If I were running a wire back to the battery for ground, I'd probably also tap in a chassis ground anyway and let the electrons decide the path of least resistance.


good advice. agreed.


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## jb4674 (Jan 29, 2015)

This was a great informational thread


Sent from my iPad using Tapatalk


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## GroundLoop (Feb 11, 2015)

For high amperage systems I would definitely use the frame if possible. Make sure both connections are mint as they will be exposed to the outside elements. Use a 1/2 or larger diameter bolt and nut and BFW (big #*[email protected]&^ wrench). Spray paint the connection when done. It will last the life of the car.


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