Alternator whine just got worse...

[packardhell1 10+ year member]

Hello all,

I just finished reading the sticky on "Engine whine and ground loop fixes", but it has not solved my problem. I've always had a little bit of whine, but it was almost unnoticable, so I didn't worry too much about it. Three days ago, it's gotten very, very loud. When I turn the Kenwood HU on, even if no music is playing, there is a loud whine. When I shift gears, I can hear it in the speakers, and when I hit bumps it crackles.

I drive an '03 Accent. I have 4 ga power and ground wire. It's grounded to a solid metal piece in the trunk. The RCAs and remote wire are run on the opposite side of the car as the ground, and the RCAs are shielded. I have an MTX Blue Thunder Pro 504 amp and a Clarion EQ. Both the amp and the EQ are in the trunk. I have no subs, just regular speakers. The amp is running at 4 ohms and the gains are low.

I've checked my wiring (power, ground, and RCA) for any signs of being cut/burnt/split/damaged and I couldn't find anything wrong. I haven't recently changed anything in my stereo.

I'm thinking the deck could be a culprit - it's just a cheapie Kenwood deck (the stupid CD loading mechanism doesn't even work anymore). Does anyone have any other ideas as to what could have changed? Do RCA cables magically become unshielded? Thank you for any help you can provide!

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[DD_Dave 10+ year member]

run a ground from the battery to the amp...your car is a unibody...no frame..though you are grounded to metal it is such a high resistance it is almost like no ground at all....

 

[01 S 10 10+ year member]

some people found out it was their head unit ground, not sure if that was in the thread with the "fixes" but that might be one option.

 

[packardhell1 10+ year member]

run a ground from the battery to the amp...your car is a unibody...no frame..though you are grounded to metal it is such a high resistance it is almost like no ground at all....

That does make sense - the unibody's metal wouldn't be like a body-on-frame, huh? I will try that.

some people found out it was their head unit ground, not sure if that was in the thread with the "fixes" but that might be one option.

That head unit was a pain to get in. If I have to take that dash apart, I think I'll just get a new head unit - no sense putting another broken one in!!!

Thank you both for the information. I will try the ground from the battery and, if that doesn't work, I'll check the head unit. I really appreciate it!!

If I do end up putting a different head unit in, should I ground it to the battery also, or just somewhere behind the dash?

 

[Ominub 10+ year member]

I had this issue in my car(when i had a car) I had eventualy regrounded everything and since it was a pioneer HU I had at the time I took and grounded out the RCAs on that. Still was there but hardly noticable, had to really listen to hear it after that. Ive stayed away from pioneer since then... I liked them but cant stand the RCA screw up they have.

 

[tc3k101 5,000+ posts]

I had this issue in my car(when i had a car) I had eventualy regrounded everything and since it was a pioneer HU I had at the time I took and grounded out the RCAs on that. Still was there but hardly noticable, had to really listen to hear it after that. Ive stayed away from pioneer since then... I liked them but cant stand the RCA screw up they have.

i had the same problem except grounding my rcas fixed it completely

 

[ProgMtl 10+ year member]

either a ground somewhere....or your gains are turned up too high (have seen that problem in a lot of cars with thin body metal...like a Nissan Xterra)

 

[packardhell1 10+ year member]

I had this issue in my car(when i had a car) I had eventualy regrounded everything and since it was a pioneer HU I had at the time I took and grounded out the RCAs on that. Still was there but hardly noticable, had to really listen to hear it after that. Ive stayed away from pioneer since then... I liked them but cant stand the RCA screw up they have.

i had the same problem except grounding my rcas fixed it completely

I'm going to take the RCAs out of the equation and see what that does. My Clarion EQ has an aux input, which I'm using with an MP3 player. Right now, I just use the deck for its remote to turn the amp and EQ on/off (I listen to the radio occasionally, but not near as much as I do my MP3 player. A simple button push turns the aux on/off.

either a ground somewhere....or your gains are turned up too high (have seen that problem in a lot of cars with thin body metal...like a Nissan Xterra)

I don't think the gains are up too high (only ~1/4). My Polk speakers are pretty efficient, so I didn't have to have the gains up (plus I don't have a sub, which helps with less power need/power draw).

I will try taking the deck and RCAs out of the equation. I do have another question. I have two sets of RCAs going from the EQ to the amp. Both are located in the trunk, away from the power and ground wires. Do you think these could be a culprit, or would there be a need to ground them? I figured they were far enough away from the engine and power/ground wiring to be an issue.

 

[packardhell1 10+ year member]

I took the head unit and RCAs out of the picture, only using the head unit as a remote for powering on, and using my MP3 player for music/radio. It sounds fine - no whine whatsoever!!! I think I'll just get a new head unit later this summer and put new, better RCAs in when the head unit goes in (and ground the head unit/RCAs in the process). Thanks for all your help!

 

[jrwalte 10+ year member]

Take your MP3 player and connect it to the RCAs behind your HU. If you have no ground noise, then you know it's your HU and not the RCAs going to your trunk.

 

[jrwalte 10+ year member]

Also, FYI.

A battery that has a low voltage, is going bad, or if it is low on water (if it isn't a sealed bat) can actually cause alt whine in your system.

 

[packardhell1 10+ year member]

Take your MP3 player and connect it to the RCAs behind your HU. If you have no ground noise, then you know it's your HU and not the RCAs going to your trunk.

I will do that //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Stupid me, I just noticed that my RCAs going from the HU to the trunk aren't shielded - I just used one I had laying around for my home stereo. I bought good, shielded ones from the EQ to the amp, but not from the HU to the trunk.

I'm fighing the good fight against stupdity //content.invisioncic.com/y282845/emoticons/swordfight.gif.e3de6069f3ffe402fc3ab4a827365101.gif and losing //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif I can't believe I did that.