Proper Electrical Grounds - Guide and Discussion Thread

[CrEaTrE]

What to look for in a good ground:
Look for a piece of metal that is apart of the vehicle chassis and not attached to the chassis with bolts or any other methods. For example in the 95-99 Mitsubishi Eclipses there is a little back hump against the back seat that looks like it would be an awesome spot to make a ground and many people and installers make this mistake. In actuality this little piece of metal is bolted to a painted part of the chassis and thus would royally suck as a ground. All in all make sure you are grounding to the unified chassis of the vehicle if not the frame itself. Also you do not need to ground to a factory bolt. While they are convenient if you cannot find one you can simply pick a location (preferably away for rear decks and the like) and attach a self tapping screw to it. Once your grounding location has been selected if you want to be sure you have selected good spot take a meter (DMM) and run a quick wire to the negative post on your battery (doesn't need to be pretty as it will be removed when you're done with it) and measure the resistance. If you can pick up any resistance with a commercially available meter you have selected a poor ground so try again.


How to prepare your well chosen ground location:
This is simple: Simply scrape away the paint at your chosen spot. This can be done using a variety of methods. The easiest method I've found is to take a drill and a wire brush attachment and have it until you can almost see yourself. Another method is to take a flat head screwdriver or a utility knife and have at scraping away. This method is not nearly as aesthetically attractive but works nonetheless. The final method is some very coarse grit sandpaper. I personally have never used this method but i cannot imagine it not working for any particular reason


How to prepare you ground wire:
This also is very simple. USE A RING TERMINAL. If you do not have any at the time go to walmart or something and get some. They are not going to cost very much so there is no reason not to use one.


How to attach you ground:
Also extremely simple. If your chosen ground location is a factory bolt (hopefully you made sure your ring terminal fits around the bolt) simply remove the bolt ,place it through your ring terminal and reattach it to the vehicle. Now if not using a factory bolt then simply inspect both sides of your chosen location. Make sure there are no gas takes or line running under the location you have chosen. Take the shortest available self tapping screw (usually 3/4") and screw it into the vehicle.



In closing, this process is not only for amplifier installation. This process can help you when dealing with alarms and anything else I might need to find to ground.



Discuss the guide, and post your own various tips and tricks for grounding electronics in the SRT4.

[derr12]

What location in the trunk do you guys feel provides the best ground?

[CrEaTrE]

Here are two threads I found stating various locations you can try. Other options and inputs would be appreciated as well that aren't mentioned in the threads:

Grounding in the trunk

Where to ground amp?

[helotaxi]

None of this matters if you don't have a good ground for the battery. The battery neg terminal is the true reference ground for the car. The chassis is only a conductor for that ground.

I'm actually a fan of grounding back to the battery. Eliminates all the guesswork of trying to find a good ground in a sea of thin sheetmetal.