Grounding Amplifiers Properly: Optimal Car Grounding Points to Avoid Unnecessary Troubleshooting Later On
Grounding car audio amplifiers improperly is probably the most common problem I’ve seen when an amp won’t power on or is having other issues.
A bad amp ground was the first problem I ever encountered on my first ever install.
I’ve thrown together some quick tips for you to try and prevent this problem. But I put this together pretty quick, so I may have forgotten something.
Before I tell you each method, remember you have to scrape away any paint and get to bare metal to have a good ground.
This is the most important part – you need BARE METAL!
Another thing to note is that ground wire length doesn’t have to be short like you’ve always been told. My theory is companies that sell amp kits just do this so that they can put a higher power rating on the label for their kits (there’s probably some other reason they do this, though.)
But remember, you have to take into account the length of the ground when sizing your wire. So the longer you make your ground, the bigger your power and ground wire need to be.
So here’s the main methods of grounding amplifiers that work pretty good:
Optimal Car Grounding Points for Grounding Amplifiers Properly
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1. Factory Amplifier Ground
The best way (and sometimes even the easiest) is to use a factory grounding point. This can be a factory amplifier ground wire or really any factory ground wire location.
Factory grounds usually have a little stud with a nut on them and some other grounds run to them.
It’s usually easier than you think to find a factory ground. They can be found under seats or in kick panels a lot of times.
2. Grounding Amplifiers through body metal or chassis with nut and bolt
This is the next best method, especially if you just want to use the short ground that came with your amp kit.
Scrape the paint. Drill a hole. Connect your ground with a ring terminal, nut, bolt, and lock washer.
Sometimes you may not be able to get to the bottom side of the grounding point and put a nut on it. Which leads me to the next methods.
3. Nutsert through body metal
You can also use a nutsert to create a threaded hole to screw your ground into.
This can work pretty good, but I’ve seen nutserts come loose before. So be sure to drill the right size hole and use a good quality nutsert.
4. Ground amp through body metal or chassis with a self tapping screw
Honestly, this is usually what I do when there isn’t a close factory ground. I use a short self tapping screw and a star lock washer. Sometimes I’ll put an extra screw or two on the sides or straight through the ring terminal.
You’ll hear a bunch of OCD people say this method sucks and is for lazy people.
I’ve used this method several times with no issues, though. And I’ve already admitted I’m lazy.
Be sure to use a lock washer. I’ve seen grounds come loose before, but I don’t think I’ve ever had an issue with a ground coming loose when using a lock washer.
5. Run amp ground wire to the battery
Note that grounding to the body on something like the aluminum F150s won’t work. You’ll need to run your wire to a factory ground point or to the battery.
If you are ever running both power and ground up to the battery, look into a marine power wire kit. They usually come with the same length power and ground wires (sometimes connected together). Just be sure the wire size is correct for the total length of power and ground for the current your amp pulls.
So pick whatever method you think will be best for your install. You can find all my recommended grounding parts below: