Acura TL Alternator Whine - HELP!

[_Frosty_]

Hey guys,

I'm trying to finish up a pretty extensive audio install on my 2004 Acura TL, but I cannot get rid of this horrendous alternator whine. And trust me, I've scoured the interwebs, trying to find a solution to my particular problem (I know alt. whine is a rather common one), but nothing has worked. The noise was not present before I started upgrading the sound system.

Here's the rundown:

What's been installed / done?

-Image Dynamics CXS64 V.2

-JL 10w3v3-2 (in sealed, fiberglass enclosure)

-Alpine MRP-F300

-Alpine MRP-M500

For the front stage, I'm taking the FL and FR signals (full range) directly from the factory headunit. For the sub, I'm taking the factory SW signal from the HU. The factory amp has been completely removed. In its old location (passenger kick panel), I soldered RCA ends onto the speaker wires from the HU (using Kicker KISL RCA adapter and Rockford Fosgate RFIF2SW). From there, Stinger 4000 series and Stinger 8000 series RCAs are run all the way back to the trunk on the passenger side (away from power wire on the driver side).

Both amps are receiving power from the battery via distribution block. Both are grounded to the frame (sanded) via distribution block.

The front stage is using passive crossovers (installed behind glovebox), and is being powered by the F300 (4 channel, bridged). The sub is powered by the M500.

All gains were set using test tones, Ohms law, and a DMM.

What are the symptoms?

When the engine is not running, there is no noise whatsoever. As soon as the car starts, the noise ensues. The noise is like a clicking buzz sound, and comes through every front stage speaker. It directly correlates to the engine RPMs. Here is a video clip that a friend took inside his car. He has the same exact car as me, and the noise is identical to mine. His problem was solved by replacing the factory amp (which I no longer have!).



What troubleshooting steps have I taken?

I don't even know where to begin...

Things that DID NOT get rid of the noise:

-Regrounded amps to new bolt in trunk

-Regrounded factory headunit to amp ground location.

-Regrounded HU to battery negative terminal

-Soldered RCA adapters in passenger kick panel (originally used butt connectors)

-Ran RCAs outside of the vehicle from passenger kick panel to trunk

-Removed factory HU from dash

-Replaced factory HU

-Upgraded battery ground wire

-Upgraded battery to fusebox wire

-Added engine ground

-Added alternator ground

-Replaced battery (DieHard Platinum)

-Cleaned alternator positive wire

-Plugged RCAs from kickpanel into a separate stereo (to bypass amp altogether)

-Added PAC SNI-1 ground loop isolator at front and rear of vehicle (not at the same time)

Things that DID get rid of the noise:

-Unplugged speaker wires from amp

-Unplugged RCAs from amp (used muting plugs)

-Unplugged RCAs from RCA adapter in passenger kick panel

-Plugged iPhone into kick panel RCAs (to bypass headunit and all wire runs behind dash)

Summary:

Based on my troubleshooting steps, I'm confident that the problem lies behind the dash (within the wiring between the HU and my RCAs), or in the engine bay somewhere (spark plugs, wires, alternator?).

Any advice would be much appreciated. I'd be happy to answer any questions.

Thanks!

Click to read more...

 

[mylows10 5,000+ posts]

Plug a RCA to iPod plug direct into the amps see if the noise is there This will bypass the deck and either eliminate or confirm the deck is or is not he issue if not the deck. Then either it's the amp or rcas

 

[bumpasauras 10+ year member]

^^^^^^

This. I bet it's a hu issue bypass the hu like Mylowes suggested if it stops go get ya an aftermarket deck if it's still there then maybe an alt issue.. The thing that sticks out to me is the noise quits when the car is on batt power... That almost always tells me it's a charging issue or a grounding problem but if you have gone over all the grounds and then some than we will look deeper.

Well first things first bypass the deck if the problem persists try removing the charge wire that goes from alt to bat by pulling off the positive while the car is running (car should still run)and c if that kills the noise if it does than there is possibly an alt problem (have it checked at a parts store) If the hu bypass does not remedy the prob, and with the charge wire from the alt to the batt disconnected if the noise is still there with the car running then you pretty much know it's not the alt or hu unless u have a short somewhere .. But I bet one of the 2 actions will kill the noise and at least point u in the right direction

Good luck

Bet it's the hu

 

[CrossoverOre 10+ year member]

I would try getting a real loc and give that a shot

 

[thatguy12 10+ year member]

Sounds like a head unit issue. But I know those TL's well, and not a fan of their head units. If you decide it is the head unit you could do something like this> 2004-2008 Double Din dash KIT -- vancouver bc -- COMING SOON - AcuraZine Community

Bypass the factory head unit and use another of your choice for audio.

 

[_Frosty_]

Plug a RCA to iPod plug direct into the amps see if the noise is there This will bypass the deck and either eliminate or confirm the deck is or is not he issue if not the deck. Then either it's the amp or rcas

^^^^^^
This. I bet it's a hu issue bypass the hu like Mylowes suggested if it stops go get ya an aftermarket deck if it's still there then maybe an alt issue.. The thing that sticks out to me is the noise quits when the car is on batt power... That almost always tells me it's a charging issue or a grounding problem but if you have gone over all the grounds and then some than we will look deeper.

Well first things first bypass the deck if the problem persists try removing the charge wire that goes from alt to bat by pulling off the positive while the car is running (car should still run)and c if that kills the noise if it does than there is possibly an alt problem (have it checked at a parts store) If the hu bypass does not remedy the prob, and with the charge wire from the alt to the batt disconnected if the noise is still there with the car running then you pretty much know it's not the alt or hu unless u have a short somewhere .. But I bet one of the 2 actions will kill the noise and at least point u in the right direction

Good luck

Bet it's the hu

I have tried bypassing the HU and plugging my iPhone into the amps via the same RCAs - the noise is gone when I do that. So that led me to believe that it was a HU issue. However, I bought another OEM HU and I had the same noise (worse actually). It seems unlikely that both OEM HUs are defective.

To be honest, it doesn't sound safe to remove the alternator positive wire while the car is running. Don't I chance ruining other electrical components by doing that? I think I'll just have the alt. checked at a parts store (not sure how reliable those tests are though).

I would try getting a real loc and give that a shot

It's my understanding that a LOC is generally used to bring down the voltage of speaker-level signal and turn them into line-level RCAs. The LAST thing I need to do is bring down the voltage of my factory HU output. It only puts out 1 volt at max volume. I originally had a line driver installed up front to boost the low signal before sending it to the amps. The alternator whine was still present, so I just removed it.

Sounds like a head unit issue. But I know those TL's well, and not a fan of their head units. If you decide it is the head unit you could do something like this> 2004-2008 Double Din dash KIT -- vancouver bc -- COMING SOON - AcuraZine CommunityBypass the factory head unit and use another of your choice for audio.

I want to keep the OEM HU. I know it can be done.

Thanks for the advice so far guys. I know there has to be a solution!

 

[mylows10 5,000+ posts]

if you've changed the deck and the Same problem is still there. Then the loc is bad or the rcas Process of elimination you know the amps are ok. Or it's an issue in the stock wiring

 

[_Frosty_]

if you've changed the deck and the Same problem is still there. Then the loc is bad or the rcas Process of elimination you know the amps are ok. Or it's an issue in the stock wiring

That's the thing - I don't have a LOC! I have no processing from the HU to the amps, and I think that's my problem. However, I don't need a LOC (which reduces the voltage of a factory-amplified signal). My signal is coming from the factory HU which is already so low (1 volt at max volume).

I literally just stumbled across this thread and I think it may be the solution to my problem. Me very excite. Factory Signals - Audio Unit Stock Amp - Differential? - AcuraZine Community

 

[mylows10 5,000+ posts]

How are you tapped in for a signal for the amp ? Is there high level inputs in the amp ?

 

[_Frosty_]

How are you tapped in for a signal for the amp ? Is there high level inputs in the amp ?

The amp does accept high level inputs, but I just soldered on RCAs from behind the factory HU because I would not consider 1 volt to be "High Level". If I were taking the signal after the factory amp, then yes, I would have used the High Level inputs.

 

[mylows10 5,000+ posts]

The amp does accept high level inputs, but I just soldered on RCAs from behind the factory HU because I would not consider 1 volt to be "High Level". If I were taking the signal after the factory amp, then yes, I would have used the High Level inputs.

That's not the correct way to hook up the amp. Might be the issue here

 

[Slobalt]

yes your amp does take high lvl input but not via rca. Theres a plug that goes into the amp next to the rca inputs that's what you need to use for a signal.

 

[_Frosty_]

That's not the correct way to hook up the amp. Might be the issue here

yes your amp does take high lvl input but not via rca. Theres a plug that goes into the amp next to the rca inputs that's what you need to use for a signal.

Did you guys read my last comment? The amps are not receiving a high level input. The signal coming out of my headunit (or any headunit) is not considered "high level". It's a pre-amp, low-voltage signal. The only reason I would need to use the speaker-level inputs is if I were taking the signal post- factory amp. Just because my HU does not have RCA outs on the back does not mean that it shouldn't be converted into such before going to an aftermarket amp.

 

[mylows10 5,000+ posts]

Doesn't matter if you decks output is 1volt. You need some kind of converter to match the amps input voltage that's what the loc does

 

[_Frosty_]

Doesn't matter if you decks output is 1volt. You need some kind of converter to match the amps input voltage that's what the loc does

Sorry, I don't agree. A LOC is used to REDUCE the voltage of an amplified signal to make it more acceptable for an aftermarket amp. The last thing my signal needs is to have its voltage reduced.

I actually just ordered the AudioControl Matrix Plus to BOOST my signal even more before it gets to the amp RCA inputs. That should put me around 4-5 volts (same as an average aftermarket HU). The Matrix accepts the balanced inputs of my HU, and can output an unbalanced signal to work well with amps.