Another alternator whine problem

[dubdub]

Morning all, after a torturous install, I buttoned everything up only to have alternator whine.

I replaced my head unit, and sirus adapter and then also rewired my amp and installed on of Luke's boxes and amp rack... so while most of the wiring was already in place, I essentially wired in a whole new system.

It has been so long since I last had a problem with alternator whine, having my last system for almost a decade(!), I just do not know where to begin. I vaguely recall a process of unplugging the RCAs to work your way through the system to try and isolate where it is coming in. Can anyone give me some guidance of where to start?

[toointoxicated60]

paging luke ;)

[kdkool]

How / where is your amp grounded?

[Gregs///M]

Unplug the RCA input from the amp. If the noise stays, the amp is inducing the noise. Re-ground amp.

However most often when you unplug the signal from the amp, the noise goes away. That would mean the problem lies within the RCA cables or head unit.

The RCA cables should be a quality brand that is shielded. The cable itself should run down the drivers side and all power wires (including OEM battery cable) is run down the passenger side.

Try grounding the radio to somewhere other than the OEM radio harness wiring.

[dubdub]

Thanks to you both. Just forgot the logic behind the process.

Amp is grounded to the same point as the battery. Amp and wiring is same as previous install, but was unwired/rewired during the process.

The RCA and all the power/ground cable is quality and of appropriate size.

[dubdub]

Realized last night that the sound becomes a lot more pronounced and adds a click, when I step on or off the brakes. Does that help localize the issue?

[Hellabad]

I have had success by grounding the head unit to the amp, and not to the sheetmetal anywhere.

Run a black wire, all the way back to the amp, and DO NOT ground the head unit up front.

Also, run all the amp input cables down one side, and the power/ground/blue turn-on wire down the other side of the car.