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Tricked out Ram
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Discussion Starter #1
Ok, I have got a 04 Dodge Ram with everything you see in my signature but for the sake of reading I have a Pioneer AVH-P5700DVD for my HU. As the title reads, I have some alternator whine I cannot track down or get rid of. I will try to explain the layo9ut as best I can and as always please ask if I leaving something out.

My power and remote go down the drivers side while my copper shielded twister pair RCAs (2 pair) go down the passengers side. My amps are mounted behind the rear seats against the wall with both having 6” to 8” 8ga grounds going to a solid distribution block and then out of that with a maybe 8” 4ga ground to a solid bolt a star washer.

My switched 12v+ power I am pulling from my OEM harness as well as the ground. My constant 12v+ I am pulling from my upper most cig lighter.

There are two grounds that come out of the HU harness. One is a solo wire and the other runs with the yellow wire which goes through a black box which we all know to be a EMI/EFI box (electrical magnetic or frequency interruption).

In the schematic of the HU it shows both grounds going to the same place so that is what I did and again, they go to the ground in the OEM harness.

Now here is what I have done……

1) For the sake of testing and not a permanent resolution, I tried 2 different ground loop isolators but they did not help at all.

2) I have tried different ground locations and separated the 2 ground wires from the back of the HU.

3) I have used alternate power 12+ sources. I have a small power inverter under my front seat that powers my xbox 360 and gets its power directly from the battery and pulled power from it for testing.

4) I also used a new and different pair of RCAs and ran these directly from point A to B meaning from the HU directly to the back and into the amp without rerouting them around anything.

5) All of this was done with the HU pulled out of the dash because I wanted to have it away from all the other wires in the dash. When the fan blower is on high I get feedback from it also which is why I tried different grounds and power sources.

I don’t think it could be the amp itself because the pitch varies with the engines RPM and not a constant tone. Although I do have a few extra feet of RCA cable in the back (but are laid out straight and not coiled up), this could not be the issue because I bypassed all of it with new RCAs.

So I am at a loss here. Did I miss anything and can someone please help out a bit?
 

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'11 5.7L R/T Classic
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When and where did you buy your pioneer head unit from? Ground loop isolators are wasted money. A 2 week old bloody bandaid for a shark bite. Pioneer sent out quite a few players with bad internal grounds for the RCAs about a year ago. There's a DIY fix to this, but I'd have to do some major digging to find a good walkthrough with pictures. Mine has this issue, and it's been solved, but it was the god-aweful variety whine.

How bad is the whine? Feint but noticeable or obnoxiously god-aweful can't drive my truck bad?

Is the star bolt a seat belt bolt going down through the cab's floor, or one above the floor (back wall or pillar)? Did you properly prepare the grounding location (scrape the paint shiny?) Are you using non conductive washers (probably not the problem)?
 

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I am your Father
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2,365 Posts
My switched 12v+ power I am pulling from my OEM harness as well as the ground. My constant 12v+ I am pulling from my upper most cig lighter.
There's your ground loop.

Step 1: Throw away all those filters that you bought, they can sometimes mask a problem but they cannot actually solve it.

Step 2: Attach the head unit grounds to a 10ga cable, and run it to where you have your amplifiers grounded, and connect it there. Do not allow the chassis of the head unit to touch ground, and do not connect the ground wires in the factory wire harness or touch the new ground that you've run.


...For the sake of testing and not a permanent resolution, I tried 2 different ground loop isolators but they did not help at all...
Yeah, they never do.



... don’t think it could be the amp itself because the pitch varies with the engines RPM and not a constant tone. Although I do have a few extra feet of RCA cable in the back (but are laid out straight and not coiled up), this could not be the issue because I bypassed all of it with new RCAs...
There's an easy test for this...
Do you hear the noise if you pull the RCA's out of the amplifier, and then place "Null Plugs" in their input, and then start the truck up?
 

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Tricked out Ram
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12,635 Posts
Discussion Starter #4
When and where did you buy your pioneer head unit from? Ground loop isolators are wasted money. A 2 week old bloody bandaid for a shark bite. Pioneer sent out quite a few players with bad internal grounds for the RCAs about a year ago. There's a DIY fix to this, but I'd have to do some major digging to find a good walkthrough with pictures. Mine has this issue, and it's been solved, but it was the god-aweful variety whine.

How bad is the whine? Feint but noticeable or obnoxiously god-aweful can't drive my truck bad?

Is the star bolt a seat belt bolt going down through the cab's floor, or one above the floor (back wall or pillar)? Did you properly prepare the grounding location (scrape the paint shiny?) Are you using non conductive washers (probably not the problem)?
I know Ground Loop Isolators are junk and I wasnt using them to correct the issue but rather to help identify it. I assume THIS is the fix you are speaking about on the Pioneer issues. I have read over it and it makes sense although I ran out of time and daylight yesterday. Yes the noise is faint but noticable and enough to drive me nuts because I know it isnt supposed to me there. Good Q on where the ground bolt it. It isnt a seat bolt (dont they have that blue thread-loc on the anyway) but I didnt use the bolt on the back wall where the child restraint harness is at. I did scrape and clean it well with a sanding disc and then fine grit paper. I dont know which metal the bolt is but I can always go with SS or a grade 5 or 8 bolt.
 

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Tricked out Ram
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Discussion Starter #5
There's your ground loop.
Pulling power from the cig lighter cant be the issue because when I pulled power from and alternate source (12v+ off my inverter that goes directly to the battery) it was still there. I tried both different ground locations and different power sources.

Step 1: Throw away all those filters that you bought, they can sometimes mask a problem but they cannot actually solve it.
I know, I wasnt trying to solve it with them but just trying to use them to identify the issue.

Step 2: Attach the head unit grounds to a 10ga cable, and run it to where you have your amplifiers grounded, and connect it there. Do not allow the chassis of the head unit to touch ground, and do not connect the ground wires in the factory wire harness or touch the new ground that you've run.
I read this over on www.the12volt.com and have it bookmarked as something to try today when I get home from work. I will let you know the results.

Yeah, they never do.
Again, wasnt trying to fix it with them but only to diagnose.

There's an easy test for this...
Do you hear the noise if you pull the RCA's out of the amplifier, and then place "Null Plugs" in their input, and then start the truck up?
I did pull the RCA yesterday and the noise went away (again leading me to believe it wasnt the amp). However, I also used a new set of RCAs and went directly from the HU to the amp and didnt route it around anything (I went directly from point A to B) and still got the hum.

I am really leaning towards the HU using the shield of the RCAs as ground and MAYBE my ground on the amps that goes to the bolt on the rear wall. Its not a seat bolt but it is the bolt that is normally used for the child restraint. Im going to go to Lowes today anyway so while I am there I am going to a new bolt and chase the threads with a tap.

I will let you guys know what I find and really appreciate your assitance because this is annoying.
 

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I am your Father
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2,365 Posts
Pulling power from the cig lighter cant be the issue because when I pulled power from and alternate source (12v+ off my inverter that goes directly to the battery) it was still there.
+12v probably isn't the problem. You stated that you're getting ground at the factory harness. That's very likely the source of the ground loop.



...I did pull the RCA yesterday and the noise went away (again leading me to believe it wasnt the amp)...
Ok, that eliminates the amp itself, now you've just got to add components one at a time until the noise comes back, to find the source. Add the RCA's, but don't connect them to the head unit. Does the noise come back if the RCA's are connected to the amp, but not the head unit?

If it's still gone, you've either got a bad ground at the head unit, (Assuming that the head unit is the only other item in the signal chain) OR the head unit is defective.
 

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Tricked out Ram
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Discussion Starter #7
ok THX. I understand what you are trying to do with the RCAs to the amp and not the HU. Would it also be the same as running the RCAs from the HU to the amp but removing the shield off the end of the RCA plug to see if it is grounding through the RCA?

Im just trying to get all the ideas while I am at work so I can apply and rule out things when I get home today.
 

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I am your Father
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2,365 Posts
ok THX. I understand what you are trying to do with the RCAs to the amp and not the HU. Would it also be the same as running the RCAs from the HU to the amp but removing the shield off the end of the RCA plug to see if it is grounding through the RCA?

Im just trying to get all the ideas while I am at work so I can apply and rule out things when I get home today.
Not in this particular case. In this particular test, you're testing for "Radiated Noise" generated by running the RCA too close to some noisy electrical component, or your checking for a bad RCA cable.

However... De-coupling the shields of an RCA cable is sometimes the solution to noise like this, when your head unit uses a "Grounded" shield, and your amp requires a "Floating" shield.
 

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'11 5.7L R/T Classic
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My guess is the RCA outs on the head unit. You can jimmy rig the RCA to deck chassis ground by just wrapping a wire in a figure 8 around each pair, making a loop and putting that through a head unit screw. No need to solder anything yet, just be sure you wrap them in electrical tape to make sure nothing touches metal to metal. Big fire hazard.
 

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Tricked out Ram
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Discussion Starter #10
Well I wasnt going to make anything permantent without testing it first. SO I used my DMM leads and made a jumped and when going from RCA shield to radio chassis ground the whine did go away. So after that I went and got my iron from the toolbox and made a permanent connection. With no more whine it sounds A LOT better.
 

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I am your Father
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2,365 Posts
My guess is the RCA outs on the head unit. You can jimmy rig the RCA to deck chassis ground by just wrapping a wire in a figure 8 around each pair, making a loop and putting that through a head unit screw. No need to solder anything yet, just be sure you wrap them in electrical tape to make sure nothing touches metal to metal. Big fire hazard.
I think I'm confused now. Please explain how an exposed ground is a fire hazard. If it's really a fire hazzard, do you wrap every piece of sheetmetal on your entire truck with electrical tape? If so, I'm gonna need A TON of electrical tape for my new truck. I bet I could use a whole roll of electrical tape on just a single fender. I've been driving it around for a couple of months now, and I guess I've been really lucky that the whole thing didn't burst into flames!
 

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BYO Plastic Cutlery
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210 Posts
I'm leaning toward the part about a bad batch of HUs. I've heard about it before.
As for a GLI - I thought you only need to isolate a ground if you added an amp AND it's created a ground loop AND that loop allows RFI from the ignition system(that, not the alternator, is the source of the noise) to get into the wires thereby requiring the loop to be isolated. I understood any other use is misuse and won't yield any improvement.
I also have observed that different vehicles react to installations differently. Adding a DVD player(which creates a loop) to an aftermarket HU in the 98 Voyager did not create any noise, but the same palyer in an MPV did. In fact, any player when combined with the Clarion in the MPV makes a noise. What cured it was adding noise filter to the power wires of the DVD player. There was still a tiny amount of noise and the GLI added to the output of the DVD player DID WORK on that. It is important to keep that GLI far from any radiating energy source like the instrument panel, HU, amps, anything. I learned that the hard way. I think that's why people think they don't work. That and they're meant for smaller amplitude noise like how it worked in my situation.
There can also be noise from the radio antenna but if there is it's usually very faint. They make a filter for that too.
 

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'11 5.7L R/T Classic
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I think I'm confused now. Please explain how an exposed ground is a fire hazard. If it's really a fire hazzard, do you wrap every piece of sheetmetal on your entire truck with electrical tape? If so, I'm gonna need A TON of electrical tape for my new truck. I bet I could use a whole roll of electrical tape on just a single fender. I've been driving it around for a couple of months now, and I guess I've been really lucky that the whole thing didn't burst into flames!
The real danger comes from adding extra wires into an already compact area, and the odds of a power wire coming in contact with your new ground wire increase. It was just an extra caution. If you want to be really careful, you can buy electrical tape in 10 roll bundles, and I'm sure I can get you the number for a manufacturer to cut down on the cost of wrapping your whole truck Nutz. I guess if you have power wires laying around the fenders that might be questionable, you should probably go ahead and wrap the whole thing. I'm just looking out for the guy, and I know DIYers sometimes don't spend hours making sure every wire is perfect. Hence half the posts in this subforum.

Incidentally, what are you driving now? I haven't been around in awhile, but I know you weren't happy at all with your.....'07(?) ram.
 

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I am your Father
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2,365 Posts
The real danger comes from adding extra wires into an already compact area, and the odds of a power wire coming in contact with your new ground wire increase.
My point was: Why not simply protect the +12v wires, instead of every piece of metal on the truck?

It was just an extra caution. If you want to be really careful, you can buy electrical tape in 10 roll bundles, and I'm sure I can get you the number for a manufacturer to cut down on the cost of wrapping your whole truck Nutz...you should probably go ahead and wrap the whole thing...
When I get back home, I'm going to make sure I wrap the entire truck in electrical tape, just to keep it from bursting into flames. (per your recommendation) :tup: I'm kinda close to the Arctic circle right now, so with these temperatures the electrical tape won't stick.

Incidentally, what are you driving now? I haven't been around in awhile, but I know you weren't happy at all with your.....'07(?) ram.
I don't think anyone would have been happy with that thing. Dodge had to buy it back from me, and crush it.

In the summer months, I drive my little convertible. In the winter months, when I need to tow my snowmobiles, I drive this:New Truck
 

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Tricked out Ram
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Discussion Starter #15
Well I understood what what trying to be said. Im not no car audio god but Ive dont plenty of full installs in my years. In this case I had tried and went through everything I possibly could have. Before I gut my Pioneer AVH-P5700DVD I was using a Pioneer DEQ-7600 as my with everything (audio and movies) coming from my Xbox. I remember it wasnt as clear as it should have been simply because the DEQ doesnt have enough voltage on the RCAs to feed the amps a good clean signal. But I remember more was that I didnt have any whine. No wires being used changed from the DEQ to the AVH. All in all I am glad to see it was something other than me or something I did during the install. Again, THX to everyone and hopefully this will help any others who might have this issue.
 

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BYO Plastic Cutlery
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When installing instrumantation or fire alarm cables that have a foil shield, That shield's purpose is to prevent any RFI from entering the signal. It must be grounded at the source end and kept insulated at the other end. Along the way, if there are any joints made between cables, the shield must be joined and insulated from touching the box or any ground. You can see why they call it a floating shield. If the other end were grounded, then that is a ground loop. In that state, the shield is unable to do any shielding.
 

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I didnt have to read much past your signature. Your AUDIOBAHN amps have screwed your Diode in your head unit, the remote turn on lead on the Audiobahn amps shorts out a diode on your circuit board in your head unit, there is no way to fix it, changing amps now will not fix it, your only hope is to run a diode on the ground side of your rca jack and it will calm it down but will not completely get rid of it. I know because I just replaced my head unit that Ive had for a few years and my audiobahn 1801 did this to my head unit, Memphis and audiobahn amps are NOTORIOUS for this. If you dont want to get another Head unit right now, a Pac ground loop isolater will get some out, but you will not have this fixed until you get a different head unit, and If you do, I suggest doing a RELAY for the turn on lead!
 

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Tricked out Ram
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Discussion Starter #18
I didnt have to read much past your signature. Your AUDIOBAHN amps have screwed your Diode in your head unit, the remote turn on lead on the Audiobahn amps shorts out a diode on your circuit board in your head unit, there is no way to fix it, changing amps now will not fix it, your only hope is to run a diode on the ground side of your rca jack and it will calm it down but will not completely get rid of it. I know because I just replaced my head unit that Ive had for a few years and my audiobahn 1801 did this to my head unit, Memphis and audiobahn amps are NOTORIOUS for this. If you dont want to get another Head unit right now, a Pac ground loop isolater will get some out, but you will not have this fixed until you get a different head unit, and If you do, I suggest doing a RELAY for the turn on lead!
Not trying to be rude but you really need to go back and re-read my posts. The amps were not the issue because when I was using the DEQ-7600 as my HU there was no issue. As soon as I changed HUs to the AVH-P5700DVD the noise came. None of the wires or RCAs changed. I will beg to differ on your opinion of not being able to rid myself of this issue without changing HUs because I did resolve this. I have no more whine and (again) through my posts I explained how I did by soildering a lead wire from the shields on my RCAs to a ring terminal that goes to the chassis of the radio. I did better than calming the noise down. I eliminated it altogether. Ground loop isolators did nothing. I explained that way back on my first post. I really appreciate your offer in helping though.
 

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'11 5.7L R/T Classic
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I didnt have to read much past your signature. Your AUDIOBAHN amps have screwed your Diode in your head unit, the remote turn on lead on the Audiobahn amps shorts out a diode on your circuit board in your head unit, there is no way to fix it, changing amps now will not fix it, your only hope is to run a diode on the ground side of your rca jack and it will calm it down but will not completely get rid of it. I know because I just replaced my head unit that Ive had for a few years and my audiobahn 1801 did this to my head unit, Memphis and audiobahn amps are NOTORIOUS for this. If you dont want to get another Head unit right now, a Pac ground loop isolater will get some out, but you will not have this fixed until you get a different head unit, and If you do, I suggest doing a RELAY for the turn on lead!
I hadn't heard that before, and I'm glad you posted it. Something to keep in mind if I hear about a similar issue in the future.
 

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Not trying to be rude but you really need to go back and re-read my posts. The amps were not the issue because when I was using the DEQ-7600 as my HU there was no issue. As soon as I changed HUs to the AVH-P5700DVD the noise came. None of the wires or RCAs changed. I will beg to differ on your opinion of not being able to rid myself of this issue without changing HUs because I did resolve this. I have no more whine and (again) through my posts I explained how I did by soildering a lead wire from the shields on my RCAs to a ring terminal that goes to the chassis of the radio. I did better than calming the noise down. I eliminated it altogether. Ground loop isolators did nothing. I explained that way back on my first post. I really appreciate your offer in helping though.
Shouldnt have to ground the sheilding on any RCA, but you got yours fixed and its good so congrats. I read all your posts, I said ground loop isolators might get some out. Obviously it didnt. All I was trying to put out there is your radio DOES have an issue and what you did was a great fix for it, but thats the way it will have to be ran from now on. Some of the different year and model H/u used different circuitry. But my main thing is I didnt want anyone doing this same stuff that alot of people have by running Audiobahn and Memphis amps, and they mainly have issues with Pioneer H/u due to remote turn on circuitry! It kills the diode and there is bad engine noise thats totaly annoying. Just sharing my experience from competitions and from many other installers out there that have seen the same thing.
 
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