HELP!!! Alt. Whine, I've Tried EVERYTHING

[budahbuddy803 10+ year member]

Things that may be causing this issue:

2009 Pontiac G5 (Base Model)

Pioneer AVH-3700BHS -

AVH-X3700BHS - <b>NEW!</b> - DVD Receiver with 6.2" Display, Bluetooth®, Siri® Eyes Free, SiriusXM-Ready™, HD Radio™, Android™ Music Support, Pandora®, and Dual Camera Inputs | Pioneer Electronics USA

Precision Power Phantom P900.5 - P900.5 - Phantom - Amplifiers - Products

Stinger 6 CH. RCA -

http://www.amazon.com/Stinger-SI4617-17-Foot-Professional-Interconnects/dp/B005C6HZCI

Kinetik HC1200 -

Kinetik HC1200-BLU 1200 Watt 12V High Current AGM Car Audio Power Cell

Progression of troubleshooting:

1.) Moved amplifier ground from below the factory battery ground to the actual negative terminal on the battery

2.) Moved amplifier ground from negative terminal to ~12" from the amp. Sanded the chassis down to shiny metal and have a very secure ground

3.) Grounded the HU to a nice, shiny, secure chassis location

4.) Unplugged the antenna to check for issues

5.) Grounded the HU RCAs to the chassis of the HU

6.) Unplugged the RCAs from the HU, started the car, and got a hiss/whine so I know the issue is with the amplifier

7.) Turned the high and mid gain down to as low as it would go and still have the same audible hiss/whine. I figured with the lowest gain signal, the hiss/whine would subside, at least a little bit, and it did not.

I am kind of out of options from all the things I have read. Any other suggestions? MAYBE the RCAs are bad, but they are brand new, twisted, with good reviews so unless I received a faulty set, that should not be the issue. Also, my battery is in the trunk, RCAs are ran down the center console, and the only interaction the power wire and RCAs have it a 1/4" section where they cross, feeding into the amplifier.

I don't do well taking a lot of detailed pictures and I didn't take any pictures today of the new HU ground, new amp ground, HU RCA ground, etc, but I am knowledgeable enough to know that my previous 7 troubleshooting steps were done correctly.

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[budahbuddy803 10+ year member]

Here is a "build log" if it helps any:

http://www.caraudio.com/forums/car-audio-build-logs-cars-trucks-suvs/615588-09-pontiac-g5-build.html

 

[budahbuddy803 10+ year member]

Bump for suggestions

 

[wew lad 5,000+ posts]

OEM alternator? Might have a bad diode. If you unplug the RCAs and it's still there, definitely a noise problem with the amp, power wires, remote wire, speaker wires, and the electrical system overall.

What kind of power/gnd are you running, what size? Do you have the ONE amp in the back of your car? or is there multiple things grounded to your chassis.

first thing id try would be to rule out the source for good 1) use 3.5mm aux to RCA's with your phone or another source 2) ground the headunit to the same point your amp is grounded with a long thin wire.

After that, considering you've tried nearly everything, I would start looking at your power wiring and ground wiring under the hood. From there, look at your alternator. Get it tested, you could have a bad diode.

 

[budahbuddy803 10+ year member]

OEM alternator? Might have a bad diode. If you unplug the RCAs and it's still there, definitely a noise problem with the amp, power wires, remote wire, speaker wires, and the electrical system overall.
What kind of power/gnd are you running, what size? Do you have the ONE amp in the back of your car? or is there multiple things grounded to your chassis.

first thing id try would be to rule out the source for good 1) use 3.5mm aux to RCA's with your phone or another source 2) ground the headunit to the same point your amp is grounded with a long thin wire.

After that, considering you've tried nearly everything, I would start looking at your power wiring and ground wiring under the hood. From there, look at your alternator. Get it tested, you could have a bad diode.

Yes, OEM alt. When I unplug my RCAs from the amp, the noise is not there. When I unplug the RCAs from the CD player (still plugged into amp), the noise is there

4 awg wire into my single 5 channel amp. Only things grounded in the trunk are my amp and the factory battery ground.

What do you mean by "start looking at your power wiring and ground wiring under the hood?" My main (only) battery is located in the trunk. Are you talking about check the wiring at the alternator? Where would I get my alternator tested, Autozone type place?

 

[wew lad 5,000+ posts]

I don't know how your car is setup but my point was to check your power and ground. With your battery in the trunk and the block up front with the alt, you might want to run a better positive and negative to the battery in the back.

Generally yes auto parts store has the equipment, the best place to get it tested would be at a small mom and pops type place that you can trust. They usually have the load testing equipment that's necessary to really tell if an alternator is bad or not.

That's one of the last things I'd try though, the problem generally lies elsewhere. Might be a bad amp or any of the other things I mentioned.

Keep in mind the chassis isn't always the best current carrying material for high current applications such as your amplifier, after about 8 feet or so I've read that it's worth it to run a separate copper wire.

 

[budahbuddy803 10+ year member]

I don't know how your car is setup but my point was to check your power and ground. With your battery in the trunk and the block up front with the alt, you might want to run a better positive and negative to the battery in the back.
Generally yes auto parts store has the equipment, the best place to get it tested would be at a small mom and pops type place that you can trust. They usually have the load testing equipment that's necessary to really tell if an alternator is bad or not.

That's one of the last things I'd try though, the problem generally lies elsewhere. Might be a bad amp or any of the other things I mentioned.

Keep in mind the chassis isn't always the best current carrying material for high current applications such as your amplifier, after about 8 feet or so I've read that it's worth it to run a separate copper wire.

Thanks. Now I remember why I strayed away from audio for the past few years. I just can't get a "plug and play" system installed. There is ALWAYS an issue of some sort that results in "buy more stuff to fix the issues you introduced."

 

[budahbuddy803 10+ year member]

Regardless, I'll try a set of RCAs to my phone and grounding the HU to the same ground as the amp. I already have a spare 14awg wire ran to the trunk so that should be easy.

 

[wew lad 5,000+ posts]

I went through the same things, and I currently am. That's a huge part of the hobby. Troubleshooting is by far one of the most common time consuming things there is for car audio lol

let me know if anything changes, after you do that you can be 99% sure the source and RCAs are fine. when you ground the headunit to the back of your car, if just the wiring harness ground doesnt change anything, try grounding the case and RCAs. This is literally all I can think of to check the source for problems.

other things to keep in mind are where/how your amp is mounted (dont mount it to metal), where your remote wire is run, and the distance from your amp ground to your alternator (alternator case is negative)

 

[budahbuddy803 10+ year member]

There may be an issue with the factory electrical system. Having the battery is the trunk is convenient, but the long runs of smaller wire can cause issues. The alternator is very far from the battery and amplifier. Amp is mounted to the top, back of the subwoofer box. Remote wire is ran with the RCAs... from the HU, through the center of the vehicle.

What do you mean grounding the case and RCAs? I have grounded the RCAs @ the HU to the chassis of the HU.

 

[wew lad 5,000+ posts]

Okay good so you know that's not ideal, and may be a part of the problem. Sounds like you have the wiring run properly for the sensitive stuff.

I'd run a 0 awg from the alt pos to the batt pos in the back, then run a 0 awg from your alternator negative (preferably the mounting bolt or case, as close to the alternator case as possible safely) and then run that negative directly to your chassis ground for your battery negative and then upgrade the wire from your back battery to ground to a 0 awg.

I meant run a jumper wire from a screw on the case of the hu and splice it into your ground that you run back to the amp ground.

get a fuse to protect the wire from the alt pos to batt pos

 

[michaellane 5,000+ posts]

Tbis is what I came here to say

OEM alternator? Might have a bad diode. If you unplug the RCAs and it's still there, definitely a noise problem with the amp, power wires, remote wire, speaker wires, and the electrical system overall.
What kind of power/gnd are you running, what size? Do you have the ONE amp in the back of your car? or is there multiple things grounded to your chassis.

first thing id try would be to rule out the source for good 1) use 3.5mm aux to RCA's with your phone or another source 2) ground the headunit to the same point your amp is grounded with a long thin wire.

After that, considering you've tried nearly everything, I would start looking at your power wiring and ground wiring under the hood. From there, look at your alternator. Get it tested, you could have a bad diode.

 

[mclerico83 5,000+ posts]

Okay good so you know that's not ideal, and may be a part of the problem. Sounds like you have the wiring run properly for the sensitive stuff.
I'd run a 0 awg from the alt pos to the batt pos in the back, then run a 0 awg from your alternator negative (preferably the mounting bolt or case, as close to the alternator case as possible safely) and then run that negative directly to your chassis ground for your battery negative and then upgrade the wire from your back battery to ground to a 0 awg.

I meant run a jumper wire from a screw on the case of the hu and splice it into your ground that you run back to the amp ground.

get a fuse to protect the wire from the alt pos to batt pos

x2 id run my own positive and negative runs from alternator and battery. ground the positive run at both front and rear of car.

 

[budahbuddy803 10+ year member]

x2 id run my own positive and negative runs from alternator and battery. ground the positive run at both front and rear of car.

I imagine that will help A LOT. Looks like I am moving at the end of the month and won't have much time to purchase and run 0awg so I will just have to **** it up and deal with it for a couple MONTHS!!! ahhhhh