# Grounding Point - 2011 Silverado



## sirbOOm (Jan 24, 2013)

Currently grounding to the rear-most back seat bolt. Shaved the paint, etc. Getting ground loop noise which I had isolated to something else but now that it's gone and I've put in a head unit, I'm getting the loop noise (alt whine) albeit barely noticeable - but I notice. Anyone put a system in a Silverado/Sierra and have a good grounding point? I'll drill if I have to but I'd rather not. My grounding point resistance is minimal but who knows... thanks.


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## [email protected] (Jun 12, 2008)

Run your ground back up to the battery in front. Its a truck so it shouldnt be much wire.


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## sirbOOm (Jan 24, 2013)

It's an extended cab truck and that'll amount to quite a bit of wire actually as the battery is on the opposite side from where the wire runs in the cabin. Nobody else with a Silverado has had to do that - I'm wondering if I should try a battery in the back by the amps. That said, I posted the following on the Silverado forum hoping someone could offer some insight on that specific truck.

I was running an AudioControl LCQ-1 as both a line level converter (to RCAs) and some processing. I went to a Rockford Fosgate 3SIXTY.3 and now I have severe alternator whine. I replaced the RF 3SIXTY.3 with a different unit, same issue, so I'm figuring the LCQ-1 was filtering this noise. You do not hear this noise when you connect directly to the amplifiers with the RCAs. 

One thing I noticed is that when I removed my stock head unit when I was preparing to switch to an aftermarket was that a latent high pitched sound disappeared. I had thought that was just the climate control system running but apparently not - maybe this is an issue? I've gone through every single possible step for identifying where the alternator whine is coming from to the point of literally removing speakers so they couldn't possibly be near any source of interference. I've followed every online guide with one exception: I haven't run a different power wire or ground for the head unit. The only thing that removes the whine is literally disconnecting my entire system - all speakers. If one speaker is plugged into the amplifier (Kenwood XR-5s), I hear the whine - doesn't matter which speaker. My grounds are showing 0.00 ohm resistance and a 0.00 on the DCV at the alternator's ground, my amplifier's ground, and the 3SIXTY.3's ground. The head unit ground (OEM wire) is also fine on the DMM. 

Having disconnected my entire system and knowing what to listen for, I am now noticing that this whine sound can be heard anyway. I decided to stick my ear next to the alternator while someone revved the engine and the exact same whine can be heard coming from the alternator. So again, the only thing I haven't done is used a non-factory ground for the head unit, but I decided to come here and check before I rip apart my dash again - with or without an aftermarket HU using RCAs or high-level outputs, and with our without the PAC adapter unit I still get the alternator whine when the system is hooked up. To note, I have run new speaker cables and the speaker cables that run past the power wire on the driver's side cross at a 90* angle and are about 4 inches away from the wire itself, which is the most anyone could ask of that situation and I've never before had a problem in numerous installations until now.

It seems that only when I put the 3SIXTY.3 in is when I get this issue, but like I said before I've already replaced the unit figuring it was the culprit. Oh, and I've pulled my RCAs to literally hold them suspended in the air in case they were the cause and there was no difference. They are Stinger 4000 series, which are good enough.

All that said, is it possible that my alternator itself is causing this issue? I don't have the time tonight to find a new ground for the head unit but I did test the OEM HU ground wire and it's fine.


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## miniSQ (Aug 4, 2009)

sirbOOm said:


> It's an extended cab truck and that'll amount to quite a bit of wire actually as the battery is on the opposite side from where the wire runs in the cabin.


i would not be so quick to dismiss this advice... At the very least, grab 15 feet of primary wire and use it to ground the amp to the battery...by running it outside the car. It would take 2 minutes and may save you days of troubleshooting.


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## sirbOOm (Jan 24, 2013)

I will do so this weekend - just have absolutely no idea where I'm going to hide yet another 2 AWG wire if this turns out to be the issue, especially when my resistance at the grounding point (seat bolt) is 0.00 ohm as measured on the DMM so theoretically it should be fine.  Thanks. For what it's worth, the 3SIXTY.3 and amplifiers are grounded to the same point. I just don't understand why I still hear a whine with zero audio equipment hooked up. I've never heard a whine like this in the engine bay that sounds exactly the same and occurs at the exact same time as the alternator whine I was hearing through the system. Frustrating.


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## miniSQ (Aug 4, 2009)

My brother ( owns a car audio store ), has a 2011 silverado....and it is a very noisy car. He would get electrical hiss out of the speakers when they were not hooked up to his stereo. Turns out something was defective, and chevy replaced it under warrantee. I think it was a heater relay or something.

what amp do you own that requires 2 ga ground wire?


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## sirbOOm (Jan 24, 2013)

I have a Kenwood Excelon XR-5s. It requires only 4 but I'm planning ahead with the 2AWG welding wire which is the exact same size (talking about the copper, not just the overall size) as OAWG Stinger wire I compared it to and I've also run a Kenwood Excelon XR-1s for a dedicated subwoofer amp off the same power wire/ground point. The wires going to the amps are 4AWG Kicker wire. Why the 5-channel? I should have gotten the 4-channel but I got the 5-channel figuring I'd run one amp and be happy (not so) and I already had a XR-1s so... yeah. I expect to end up with a 6-channel amp and a dedicated subwoofer amplifier so I can properly go active once I figure out the 3SIXTY.3.


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## Icefsh (Jan 20, 2013)

Have you done a big 3 upgrade? From what I have read on this forum, it has fixed alternator wine for some people. I have a 2012 silverado and am planning on doing my install this summer. Planning on doing this upgrade on my truck. Will be watching this thread to see how you fix your problem. Good luck.


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## sirbOOm (Jan 24, 2013)

I have not done the Big 3. Charging keeps up just fine so I didn't bother.


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## AndrewH (Feb 27, 2013)

sirbOOm said:


> I have not done the Big 3. Charging keeps up just fine so I didn't bother.


It's not just about charging, in fact I'd be willing to say that it's mainly about adding better grounding points with lower resistance on top of what, in your case Chevy has already done. Give it a try, it might help.


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## smgreen20 (Oct 13, 2006)

Just because you have 0.00 ohms of resistance means very little in this case. A ground loop is more likely the culprit. I'm right there with you not wanting to run a 2nd run of wire, just because it's a truck doesn't mean it's less wire. In my Sierra i have 18 feet from battery post to distro behind my rear seat. Your Tuck is the NBS as mine is not.


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## goodstuff (Jan 9, 2008)

Reground the head unit.
New spot. Not the factory ground.
If not that then star ground or back to battery. Check engine and frame grounding.


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## bobduch (Jul 22, 2005)

The problem with a seat bolt is that the bolt is zinc plated. This can cause problems. Jeff (werewolf, lycan) gave me the the way over my head explanation about why many years ago. I can tell you that moving from a zinc plated screw to a "regular" screw fixed my noise problem. And I did not change the ground location. All I did was replace the screw. hI know this sounds nuts. But I'm not BSing. This is for real.


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## goodstuff (Jan 9, 2008)

He's right^. I remember reading about that here on diyma.


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## SkizeR (Apr 19, 2011)

bobduch said:


> The problem with a seat bolt is that the bolt is zinc plated. This can cause problems. Jeff (werewolf, lycan) gave me the the way over my head explanation about why many years ago. I can tell you that moving from a zinc plated screw to a "regular" screw fixed my noise problem. And I did not change the ground location. All I did was replace the screw. hI know this sounds nuts. But I'm not BSing. This is for real.


beat me to it. i cant believe no one mentioned this. would have been the first thing i said. try that and let us know how it goes


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## sirbOOm (Jan 24, 2013)

I'll do the above. I also got some advice that where I put my crossovers is too close to the heater components and as a result I'm probably pulling in noise from that. If I plug in my iPhone to a cig lighter for power and then attach the iPhone to the stereo via the 3.5mm cable I get the loudest whine I've ever heard. Talked to a car audio shop and they said that my truck is an absolute bizznatch to avoid noise in at times. Haha... should have gotten the Ford (not the Toyota).


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## Audio Options (Aug 28, 2008)

I haven't been able to isolate the noise in mine either, I have big 3 and ground bolted directly to frame and still have slight whine.. I haven't tried regrounding the deck yet


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## sirbOOm (Jan 24, 2013)

i've been told to put a .5 to 1 farad cap in-between the alternator and the battery which will condition the power going to the battery, removing AC ripple. Apparently this works.


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## AndrewH (Feb 27, 2013)

Audio Options said:


> I haven't been able to isolate the noise in mine either, I have big 3 and ground bolted directly to frame and still have slight whine.. I haven't tried regrounding the deck yet


Try turning your gain down to as low as you can with still getting max power, that totally solved my problem and I did EVERYTHING and nothing worked, as soon as I adjusted them slightly everything is crystal clear. 



sirbOOm said:


> i've been told to put a .5 to 1 farad cap in-between the alternator and the battery which will condition the power going to the battery, removing AC ripple. Apparently this works.


I had alternator whine pretty bad, even with a 25 farad rockford fosgate capacitor, so I'm not sure that's true. As i mentioned above the only thing that finally worked was lowering my gains slightly, which just meant I had to turn the power up a couple notches more than usual, but it was totally worth it for the clear sound I'm now getting!


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## sirbOOm (Jan 24, 2013)

My gains on the speaker amp are all the way down and sub amp is one notch up. That helped but I still hear the whine. I'm having a strong suspicion running a new power wire and especially ground direct from/to the battery for the head unit is going to help as I've been isolating more and that's my hunch as a result. Just haven't done that because I'm not final on my HU installation so I was wanting to do things at once. But I do have all the wires I need to get the job done there ready to go.

I'm talking about putting the cap in-line before the battery sees a charge from the alternator - apparently that helps as apparently Silverados have an AC ripple issue as the primary source of noise. This was also a suggestion from Soundman in Cali.

Can't change the grounding point of a Silverado alternator as it grounds via its mount, not a wire. I'll use my extra wiring to reground the battery first so it has the same AWG as my amp ground. I intend to put in a second battery in the diesel battery tray so I'll try to do power wires all at the same time and the cap if regrounding the battery and HU doesn't help - probably don't have enough wires for everything right now and, while welding wire is cheap and great, the shipping isn't. Was trying to not do the big 3 as I'm still under warranty and who knows what the dealer will say if I have something wrong in the future... not that I can't make the wires look exactly stock, just bigger.

Bloody f'ing annoying!


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## Tyler285 (Apr 3, 2013)

sirbOOm said:


> I have not done the Big 3. Charging keeps up just fine so I didn't bother.


I have a tahoe and the factory big three wires look like they are about 4 gauge. So I'm not going to do it for now at least.


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## Madcow (Apr 30, 2013)

If you hook up an oscilloscope to the power and any ac ripple will be apparent. You could have a bad regulator on the alternator and the shunt to ground is bad. Or simply running a good ground to the mounting bolt could take care of it. Instead of questing you could always take a good speaker wire with alligator clips run it to your battery neg terminal and move the other end to the suspected grounding points. Or get a good clamp on ohm meter like the ones used for testing industrial electrical circuits.


Sent from the future via a wifi time portal.


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## sirbOOm (Jan 24, 2013)

Found the noise source: (1) Apparently my RCA cables were directional and I have them in the wrong direction; (2) I put my crossovers under the dash under the carpet on the passenger side right below my heater core and what not knowing that I'd go active later so I didn't want to do a whole lot of malarkey with those; and (3) I installed a capacitor for good measure to clean up the power going to the amplifiers and RF360. No more noise - one or some of those did the trick. Now I get to focus on how terrible my JBL MS-62C's sound compared to Robb's car and what not... hmmph.


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## minbari (Mar 3, 2011)

sirbOOm said:


> Found the noise source: (1) *Apparently my RCA cables were directional and I have them in the wrong direction*; (2) I put my crossovers under the dash under the carpet on the passenger side right below my heater core and what not knowing that I'd go active later so I didn't want to do a whole lot of malarkey with those; and (3) I installed a capacitor for good measure to clean up the power going to the amplifiers and RF360. No more noise - one or some of those did the trick. Now I get to focus on how terrible my JBL MS-62C's sound compared to Robb's car and what not... hmmph.


lol, you are kidding right?


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## sirbOOm (Jan 24, 2013)

minbari said:


> lol, you are kidding right?


No - are you making an a-hole comment unnecessarily? Anyway, the text on these cables was so small I had to use a magnifying glass to see the arrow and didn't think to look when I put them in. I switched it around and did the other stuff and I don't have noise. I call that a success in a vehicle that is apparently quite noisy. I then did the other stuff and called it a great success. I'm so sorry if I have offended you by mentioning directional cables or because I put the cable in in the wrong direction, bro.


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## minbari (Mar 3, 2011)

*shakes head*

so you are really going to tell me that electrons go in one direction on a piece of copper better than the other direction? 

you can call it "a-hole" comments if you want, but directional wire is BS. there are other reasons that taking out the cables and then putting them back in fixed it.


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## _Nomad_ (Dec 11, 2012)

sirbOOm said:


> Found the noise source: *(1) Apparently my RCA cables were directional and I have them in the wrong direction*; (2) I put my crossovers under the dash under the carpet on the passenger side right below my heater core and what not knowing that I'd go active later so I didn't want to do a whole lot of malarkey with those; and (3) I installed a capacitor for good measure to clean up the power going to the amplifiers and RF360. No more noise - one or some of those did the trick. Now I get to focus on how terrible my JBL MS-62C's sound compared to Robb's car and what not... hmmph.





minbari said:


> lol, you are kidding right?





sirbOOm said:


> *No - are you making an a-hole comment unnecessarily? Anyway, the text on these cables was so small I had to use a magnifying glass to see the arrow and didn't think to look when I put them in.* I switched it around and did the other stuff and I don't have noise. I call that a success in a vehicle that is apparently quite noisy. I then did the other stuff and called it a great success. I'm so sorry if I have offended you by mentioning directional cables or because I put the cable in in the wrong direction, bro.





minbari said:


> *shakes head*
> 
> so you are really going to tell me that electrons go in one direction on a piece of copper better than the other direction?
> 
> you can call it "a-hole" comments if you want, but directional wire is BS. there are other reasons that taking out the cables and then putting them back in fixed it.


Pure comedy!


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## sirbOOm (Jan 24, 2013)

Nope. That's clearly ridiculous. The shielding (not the wire) is directional and if a cheap cable is indeed different and "less good at blocking noise" than more advanced (and generally more expensive cables), then conceivably my cable has something to offer in the directional shielding (something about how the shielding grounds to the source vs. the destination). It did - audibly less noise. Then I moved the crossovers. Noise gone. If I went in the other direction and started with the crossovers, well I wonder what would have happened. Regardless, apparently a Silverado is noisy and I have no more noise. I don't claim to be as much of an apparent expert as you and Nomad are, so pardon me for exposing your cheerful and mature personalities. Thanks for the help!


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## miniSQ (Aug 4, 2009)

sirbOOm said:


> No - are you making an a-hole comment unnecessarily? Anyway, the text on these cables was so small I had to use a magnifying glass to see the arrow and didn't think to look when I put them in. I switched it around and did the other stuff and I don't have noise. I call that a success in a vehicle that is apparently quite noisy. I then did the other stuff and called it a great success. I'm so sorry if I have offended you by mentioning directional cables or because I put the cable in in the wrong direction, bro.


great job....and yes some cables are built directionally.


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