Is this a good enough ground?

[Nevalite 10+ year member]

Hey,

I found this great spot under the back seat, I sanded it down and attached my wire and wire holder, do you guys think it's going to work?

Sorry for shitty pics, its from my phone...

It's a perfect spot because I'm mounting the amp on my back seats...Only thing that worries me is that theres probably a little bit of paint under that black clamp thing...I looked in the screw hole tho and its all bare metal so it makes contact there for sure...

What do you guys think?

Click to read more...

 

[bikinpunk 10+ year member]

Looks like you need to sand it down a lot more to get to bare metal.

Additionally, do you have a DMM? If so, you can test it yourself.

 

[Echo42987 10+ year member]

seems fine.

-Nick-

 

[BASSMEKANIK 10+ year member]

you need to grind under that mounting tab not just the top of tha tab.

 

[Nevalite 10+ year member]

The contact through the thread of the bolt isn't good enough?

Will this work as is?

What would happen if it weren't grounded well enough?

 

[Trey803 5,000+ posts]

your amp wont perform 100%

 

[bikinpunk 10+ year member]

The contact through the thread of the bolt isn't good enough?
Will this work as is?

What would happen if it weren't grounded well enough?

Above...and Ground loop and some *#%^ alt whine, most likely.

It's not just the contact through the bolt...it's anything that the bolt can be influenced by...which happens to be that "plate", which is touching the painted surface. All that ties into your ground.

 

[Nevalite 10+ year member]

Because it would be really hard to remove that plate (it has 2 more bolts under the seats u can see that I can't really access) I was hoping that it would work like this...

So you say it will work but not as good as it should?

 

[Glock23 10+ year member]

grind LOTS more. we litterally mean grind ie power disc grinder.. or a wire wheel on a drill

 

[bikinpunk 10+ year member]

grind LOTS more. we litterally mean grind ie power disc grinder.. or a wire wheel on a drill

Because it would be really hard to remove that plate (it has 2 more bolts under the seats u can see that I can't really access) I was hoping that it would work like this...
So you say it will work but not as good as it should?

x2. It needs to be as close to bare metal as possible.

Again, do you have a multimeter? You can save yourself a lot of trouble if you test the ground.

 

[Nevalite 10+ year member]

I do have a multimeter, how do I test it?

Side note: this is my first install ever and this system hasn't been powered up yet, the battery is still disconnected.

 

[bikinpunk 10+ year member]

I do have a multimeter, how do I test it?

Set it to resistivity (ohms).

You'll need some extra length of wire to reach from where your ground is to the battery.

Now, take one lead of the multimeter and touch it to the ground location. Take the other lead, use some sort of wire or extended leads, and attach it to the negative battery post. Let us know what reading you get. You should be getting below .5ohms. That's a good starting point. Depending on your wire, you might have some resistivity in there.

Also, make sure you touch the two leads of the multimeter together before testing so that you can see what the resistivity of the DMM itself is. For example, touch them together and you may get .1 ohms. Then, whatever your ground spot reads, take .1 ohms off of it.

Follow?

 

[Nevalite 10+ year member]

Yeah I got it, only thing is its not a DMM its an old school multimeter, with a needle and I don't think I have long enough wire to reach the battery

 

[bikinpunk 10+ year member]

Just use some speaker wire.

 

[Glock23 10+ year member]

dont make your wires tight give them a little play. just a bit though