Ive been having problems with my d3 giving me tons of engine whine. It is so bad that i have completely stopped using my amps until i sent it away for pioneer to fix it. Well tonight i was looking at what might be the cause of the problem and i think i found it. It seems the ground wire that is used for the RCAs is not connected any more.

So I've came up with 2 possibilities:

1:I replace the RCA harness and hopefully that fixes my problems with engine whine.

2. I replace the RCA harness it does not fix my problem, but explains how the pico fuses in the HU blew.

Here is a picture of what im talking about.

Think there is a good possibility of the harness just needing to replaced??

if you have an aftermarket amp installed, the ground for that amp should be the problem. try to ground it somewhere else.

if you have an aftermarket amp installed, the ground for that amp should be the problem. try to ground it somewhere else.

I have tried that multiple times. I also used those mute plugs for the amps and i do not get any noise. I have pretty much widdled it down to the head unit.

thats weird because i was getting that noise too and i grounded my amp in another location with that had a thick piece of metal and the problem was gone. sorry i can't solve your problem

have you tried to connect all the RCA's shields together and grounding them to the radio and the radio with a 10ga to the body to ground another thing is to try a ground loop isolator remember if testing to unplug the other RCA's from the HU it's a pioneer issue as they still use a common ground system where other have used floating grounds for years as when I removed my alpine cd and installed the avic D3 it went from quiet to engine noise! nothing worked to eliminate it except the dreaded ground loop isolator...

I seem to have the same problem, (also have a few others, but will concentrate on this one for this thread) why do you say the dreaded ground loop isolator ? Does it hurt the overall sound quality or something like that?

Yes ground loop isolators kill your midrange sound quality, I've learned that firsthand.