Help with alternator whine
Ok, I have got a 04 Dodge Ram with everything you see in my signature but for the sake of reading I have a Pioneer AVH-P5700DVD for my HU. As the title reads, I have some alternator whine I cannot track down or get rid of. I will try to explain the layo9ut as best I can and as always please ask if I leaving something out.
My power and remote go down the drivers side while my copper shielded twister pair RCAs (2 pair) go down the passengers side. My amps are mounted behind the rear seats against the wall with both having 6" to 8" 8ga grounds going to a solid distribution block and then out of that with a maybe 8" 4ga ground to a solid bolt a star washer.
My switched 12v+ power I am pulling from my OEM harness as well as the ground. My constant 12v+ I am pulling from my upper most cig lighter.
There are two grounds that come out of the HU harness. One is a solo wire and the other runs with the yellow wire which goes through a black box which we all know to be a EMI/EFI box (electrical magnetic or frequency interruption).
In the schematic of the HU it shows both grounds going to the same place so that is what I did and again, they go to the ground in the OEM harness.
Now here is what I have done……
1) For the sake of testing and not a permanent resolution, I tried 2 different ground loop isolators but they did not help at all.
2) I have tried different ground locations and separated the 2 ground wires from the back of the HU.
3) I have used alternate power 12+ sources. I have a small power inverter under my front seat that powers my xbox 360 and gets its power directly from the battery and pulled power from it for testing.
4) I also used a new and different pair of RCAs and ran these directly from point A to B meaning from the HU directly to the back and into the amp without rerouting them around anything.
5) All of this was done with the HU pulled out of the dash because I wanted to have it away from all the other wires in the dash. When the fan blower is on high I get feedback from it also which is why I tried different grounds and power sources.
I don’t think it could be the amp itself because the pitch varies with the engines RPM and not a constant tone. Although I do have a few extra feet of RCA cable in the back (but are laid out straight and not coiled up), this could not be the issue because I bypassed all of it with new RCAs.
So I am at a loss here. Did I miss anything and can someone please help out a bit?
Is the engine noise barely noticeable, or is it so loud that the car next to you can hear it?
So loud the car next to you can hear it, Try this https://bcae1.com/images/rca/temporaryrcashieldrepair.html
Barely noticeable, Turn every gain control of every amp all the way down. Check to see if the noise is still there.
before I posted I had did a search for alternator whine and see where the general consensus of the board was believing Pioneer HUs had those issues and seen where you yourself had passed out that same link on many occassions. I have already read over it a bit but didn't have enough time today to try any of it. Maybe tomorrow after work I will get a chance.
Well, it seems after taking a test lead and going from RCA shield to radio chassis ground the issue went away. So I went and got my iron out of my toolbox and fixed a wire from the shields to a permanent ground and no more damn whine. THX so much for your help.
Glad I was able to help.