I had the center console and dash taken apart for a project so I decided to try and re-ground my headunit to remove the speaker whine I received after installing a Clarion 635 headunit. NO MORE WHINE!!!!

Here is what I did:

The headunit was wired in using the Crutchfield adaptor harness. The harness includes the ground wire that apparently runs all the way back to the amp before grounding. This can lead to the dreaded "alternator whine" or a variant of the same. Some post on here recommended re-gronding the wire to the chassis or other substantial structural element in the center dash. I cut the ground wire from the harness and attached it to a bolt holding the center dash in place with a large steel structural member.

Did the trick because no more whine!!! I will try to post pics soon. My advice is to NOT ground the headunit by using the harness. ground it to subthing substantial in the dash.

Care to elaborate on exactly where you grounded the wire to? Do you mean somewhere in the hole the head unit fits in? or somewhere else in the dash?

Yeah he is right. I remember when I had my grand cherokee and I installed my pioneer there was a terrible whine in the signal but I later discovered that it was because it was being grounded to the factory amplifier which was under the rear seats. I ran a 4 inch ground to some metal above the cd playe bracket and it fixed all the noise.

I had the console that surrounds the shifter and OBC out for some work. That exposed some "posts" that are clearly the structural members of the dash that run vertically. At the bottom they are anchored with some large bolts. I just unscrewed one of the bolts and ran an extension of my ground wire to the bolt. Tightened it up and no more whine!
:redspot