# Seat bolts....good grounds?



## JH1973 (Apr 21, 2017)

I'm not asking the question but I'll answer it.......generally speaking NO.I had a customer recently who I sold an integration harness for an aftermarket amp and subs.He hooked everything up and said it sounded great barring the fade and balance didn't seem to work.

A week later he emails me saying his amp is burning up and went into protect.He tries a different amp and it goes into protect.Thinking it's the low level harness I sold him I assured him that was highly unlikely and that his problem is probably linked to a grounded speaker wire,blown speaker,grounded RCA or just a bad ground for the amplifier.I really emphasized the last suggestion because he said the amp only went into protect when he plugged the RCA's in.That was a big hint because the shield on all the plugs are connected to the amps main ground.

To make a long story short he grounded the amp to the seatbolt and when I had him measure resistance to the battery ground he was getting 20ohms! So he proceeded to ground at the inner fender well(grinded down to bare metal) and got a reading of 0ohms.Needless to say all of his problems got solved,case closed.


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## FlyingEagle (Sep 22, 2017)

Good call, as many bolts go through the body and as a result they coat the bolts or worse yet, they rust up solid, so there isn't much left to connect with in terms of a clean energy efficient transfer medium. But the bolt is metal right?


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## thornygravy (May 28, 2016)

I try to stay away from any of the cars safety elements, whether it's a good grounding location or not.


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## P0234 (Jul 5, 2018)

Most seat bolts are painted or powder coated, so not surprising.

I personally try to use existing bolts because I hate drilling through cars needlessly. They already rust fast enough, and if you drill to the outside of the car, you are creating a spot that will definitely rust faster.


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## Mullings (Jan 31, 2016)

In almost every vehicle that I put the amp under the seat there’s a ground post on the front bar that the seat is bolted to, using the seat bolt looks so tacky.


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## Sine Swept (Sep 3, 2010)

Piloted bonding brush. Also nut, bolt and star washer.


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## JH1973 (Apr 21, 2017)

I like using existing bolts as well but it's not always available.I think a lot of younger inexperienced people think just because it's metal than it must be a good ground.They don't bother educating themselves about using a DMM which would prevent so many headaches.


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## BillC (Feb 26, 2017)

I use seat rail bolts and dialectic grease to clamp a copper ground lug. And just for kicks when I run my remote wires to amps or processor, I typically run a small 14 awg ground wire to bond every piece of equipment in the system starting at the head unit with attachment points along the way, like if I run a wire from deck through center console, I will strip 2 inches of the bond wire and wrap it around one of the bolts that hold down the parking brake. Even my main amp ground from battery, once it passes through the firewall, I strip an inch of it and pass it through a ground lug without cutting it and attach it to the bolts that attach the brake and clutch pedal assembly in place.. the idea being at any point in the system you have as close to zero difference in potential as possible, or as mentioned, the same ohm readings at the battery post as you do down stream. And only once have I had noise issues with an alpine 9887, turned out to be an ipod cable.


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## BillC (Feb 26, 2017)

And those seat rail bolts etc that are used get a liberal coating of dielectric grease


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