I installed my system but I'm getting a buzzing noise. It changes with the throttle so it is engine noise. I bought 2 ground loop isolators. I hooked them up to the 2 pair of RCA's and they also have 2 brown wires. I grounded them to the black wire from the harness. The buzzing is still there. Not a bit of difference. I think I'm going to go back and remove them. Would it help to ground the black wire to the car frame somewhere too?

 

I have a 5-channel Arc Audio amp mounted behind the passenger seat of my GS.

I grounded the amp to factory ground that is just to the rear of the lower part of the passenger door.

No whine or noise at all.

 

That's a good spot for the amp ground- it would be even better with the paint sanded off the panel (in the size of the lug that's on the wire), so the ground isn't reliant on contact through that (coated) bolt and its threads.

Grounding the head unit in that location, with the amp, resolved the engine whine for me, with an aftermarket deck, and the stock amp and aftermarket amps all hooked up. The other possible ground loops are through the antennae (they make an isolator for the antenna connection), and if the car is onstar equipped, through the onstar connection (not much you can do for that besides GLIs).

 

I just finished an install in my C6 vert and I had a whine that went up and down with the RPM. I finally found after taking everthing apart that I had ran the speaker and RCA cables to close to to a fuel ratio meter I have in my console. Rerouted the wires away from it and whine was gone . I had taken about everything apart by then so I stated putting everything back together and whine returned when I put the amp back in. I then found that I had pushed all the RCA wires and ground loop isolators up under the amp so you could no see them and that was also causing a whine. Rerouted the RCA cables away from amp and no WHINE . I had already grounded the RCA cables at the factory Bose NAV so I kept it that way. I removed the ground loop isolators off of the RCA cables at the amp that I installed in the begining because there was no need for them now. I thought I was OK when I ran the RCA's and speaker wires down the middle of the car and power down the passenger side. From what I've read trying to figure this out , there's a lot of ways people fix whine in the systems they install. Good luck.
THANKS RAYZZZ MY CORVETTE LIKES MY MONEY

 

A BIG-3 might help as it creates a very strong ground. Also keep all wires as isolated as possible and away from power wires, and an antenna isolator may help, check Kedar's post <CLICK HERE>, I am doing the full install next week, have the antenna things, GLI's and plan to ground each RCA off the HU, good luck

 

couple of issues there that could be happening,
1. and most common i suppose is the rca's to close to a power wire or any engine wiring at all really, i always run the power and ground wires down different routes (in my own car i run them down the door sill but have the rca's and power wires running about 2 inches apart and have the rca's covered in wire loom insulation. to check for this being the issue simply get a set of RCA's and wire the amp to the head unit and leave the wiring just out in the open and see if the noise is gone.
2. i would say a bad ground or ground wire thats too small might also be an issue, Also pretty easy to check i have a long ground wire with simple clamps on either end then i hook one to the ground wire at the battery and the other to your amp ground wire if the noise is gone you just need to make a better ground, i also check the head unit as well.
3. alternator diod trio (just replace the alternator) has lost a leg and is the culprit. Alot of guys just unplug the alternator to see if the noise goes away and thats fine "ONLY" if you have eliminated the first 2 first.
Good luck with it , paul

 

Thanks guys. This is getting more complex than I had anticipated but it is a learning experience.

 

Try to use a common ground point. Not ground your radio in one spot, amp in another..etc. Otherwise you can have a "ground loop" and get the whine.

 

I don't have an amp. At least an aftermarket amp. I just replaced the HU, that's it. I'm going to work on it Friday. I'm going to redo everything and solder it all.

 

I also had the whine and used 2 PAC SNI-1 GLI's. I mounted them between the amp and RCA's and it did the trick. I did NOT ground the GLI's. It also did not make any noticeable degradation is the sound of the stereo. Might try it since you have the GLI's.