polo1134

I installed the ipod to car and it works great as far as playing my ipod, but now I have alternator engine whine thru the speakers when driving.

You can mainly hear the whine between songs when playing the ipod, but it's really noticeable when listening to the radio. If I have the radio on and it's switched to aux with nothing playing it sounds like a cheap video game... I mean I loved Spy Hunter when I was young but not wanting to listen to it during my daily drive!

How can I fix this... please help.

Background on car 2000 Corvette coupe, 6 speed. standard stereo/CD, no CD changer.

Thanks!

EliteGreg

Ground loop is your problem. If the unit has a connection to ground, make sure its a good ground connection (and preferably the same ground the radio uses). You could use a ground-loop isolator if fixing the ground doesn't help (but they can degrade sound quality). Ones with RCA connectors can be had online for under $10.

polo1134

It was a simple installation, just unplug the factory radio harness from the back of the radio, plug in the ipod-to-car harness and then reattached the factory radio harness to the ipod-to-car harness. There was no dealing with ground wires etc...

Is there a way I can check the ground loop? There was no ground wire coming off the ipod-to-car unit that I remember, just the harness. I guess I can try a Ground loop-loop isolator.

Is there something else I can do to fix this, did I do something wrong?

I’m a novice when it comes to stereos so any info you can provide is very helpful.

Thanks.

EliteGreg

What unit is it? What kind of car? How does it hook up? My guess is there is a difference in resistance to ground between the interface and the radio. Here's an article on ground loop:

http://en.wikipedia.org/wiki/Ground_loop_(electricity)

Does the hum happen with the ipod unplugged from the unit?

polo1134

The ipod 2 car unit is the Peripheral PXDP/PXHGM4 (its the one made for the single CD stereo). The car is a 2000 C5 coupe, it has the stock stereo with single CD player and no CD changer in the rear of the car.

The PDXGM4 plugs into the back of the stock head unit, and then the stock wiring harness that was plugged into the head unit plugs into the PDXGM4. The only other wire that comes in the kit is the one that you plug into the ipod. Now the Peripheral unit does has a few white switches that need to be moved but I did it correctly following the directions.

It has been in the car for some time now and I just lived with it because I was a bone head and didn't test the unit until I had the dash all put back together. I have some time on my hands so wanted to get this fixed if possible.

I am planning on getting new speakers in the car early next year, so if I can't figure it out I may just have a professional stereo shop fix it.

Let me know if I'm missing something. I did read the link on ground loops and it makes sense, just not sure how to go about fixing it... should I try a ground-loop isolator, are they easy to install, just plug in and viola? I appreciate you help.

The Highlander

Did you get to solve this issue???

Thanks

Zorlac

Go ahead and slap me but I've had bad plug wires cause that before.

jmc3367

usually bad plug wires will come in as a tick a lot like you would hear if the plug wire were arching to ground. These cars do have some unique issues though so it's possible. whines and whistles tend to be ground loops. In his case i don't know how you would Isolate the loop without going in to the adapter he has. kinda strange. I would try another Ipod just to see and because it's easy to do.

jmc3367

One other thing is make sure all your ground connections are good on the car. Especially any from the Batt to the frame or Frame to engine or Batt to engine. I have seen factory systems have Alternator whine when connections (usually grounds) are corroded.