Hey guys...I have a couple amps and sub in the back. I never really had an engine alternator whine.

Yesterday, a buddy and me installed a dvd player, the av electronics box, backup camera and the USA Spec ipod unit. We have a terrible whine that goes up and down with the speed of the car. We bought a ground loop from circuit city and installed it on the RCA audio line (we tried it from the dvd player to the AV Electronic box and from the AV Box to the USA Spec Aux input and both places had the whine.

I can't keep driving like this. Whats the best way to start trying to figure out where this whine is coming from? Redo all my grounds? Buy another Ground loop?

Any help would be great.

Thanks

Jason

 

Remove one component at a time and see if you can isolate the problem to a particular device.

I wouldnt bother with a ground loop isolator. First I would check the RCAs and ensure that they are running next to any wires that may induce noise (especially power wire for the amps). If that doesnt work, I would redo all grounds making sure they are on bare metal of the chassis and not on a reinforced area (such as seat belt bolt).


If possible have all grounds at a common point using a distro block. If that still doesnt work try grounding directly to the negative battery terminal. If that still doesnt work try different grounding locations for different devices. The common wisdom is that the shorter the ground wire the better, but be aware that this isnt always the case. I've seen installs where a ground directly to neg battery terminal was the best way to fix noise issues. Every car, even of the same make and model are different when it comes to noise.

Alt whine is a bitch to get corrected sometimes. It takes a lot of playing around with different ground spots sometimes.

 

Thanks saitcho. The ground loop did nothing. I guess its time to start diagnosing and figuring out where the problem is. This is going to suck as I got wires and devices everywhere. Arrrrg

you think its the ground and power wires to close together or is it an isolated bad ground?

 

I would check the USA SPEC first if you are going to start component by component. I never had a hint of whine, but after I installed that, I get mild whine. Yours may be an exaggerated case.

 

Ground and power wires can be as close together as you need them to be. Its RCAs and power wire that dont play well and may cause noise. Check this first by playing around with the wires. If they run side by side its usually a problem, but having them cross each other perpendicularly usually wont matter (but not always). If you still have noise then start the component by component check and redo your grounds when necessary. I would take khsonic's advice and start with the USASPEC component.

 

are you using an aftermarket or stock HU?

 

Stock HU (I had the NAV and couldnt go aftermarket on the HU).

 

I have a similar problem. I put a Rockford amp in back for my sub. I have a separate power switch to turn it on. Even with the radio off, there is a little whine. Power runs up the passenger side to the battery. -ve is grounded in the trunk using 4 gauge wire (I drilled my own grounding point). The whine increases if the interior lights are on (door open). I have checked and re-checked the ground. Any ideas?