# Headunit making noise do I need a new ground?



## ccapil (Jun 1, 2013)

Just installed my brand new headunit, it's making noise!
It's a kenwood kdcu5076bt, brand new and new rcas etc, the amp ground etc is fine, it's the headunit. The sound is a high pitched whining static type noise, there is no noise at all when the car is "off" or when the headunit is on standby, the noise only occurs when the car is on "on" in the key position, with the volume down and gets louder when u turn it up. With the car going it sort of gets louder with the rpms. It's grounded through the factory harness, should I make my own ground to the chassis or would adding a new short run of 4 gauge wire from my neg battery terminal to the chassis of the car help?

Cheers.


----------



## syc0path (Jan 23, 2013)

I would try grounding the outside shielding of the RCAs to the chassis of the HU -- that might make the whine go away.


----------



## Alrojoca (Oct 5, 2012)

similar issue on this thread. Avoid using the ground from the harness kit to connect the new HU. http://www.diymobileaudio.com/forum/general-car-audio-discussion/155481-noise-my-new-system.html


----------



## ccapil (Jun 1, 2013)

I regrounded my hu behind the dash on a piece of metal box section frame. I grounded the paint down and it helped a tiny bit but the noise is still there? When I turn my hu on is sounds static type of noise then I start my car and it goes to a high pitched noise. Would upgrading the battery negative ground help ? With 4 gauge the same as my power wire for my amp? I'm pretty sure it's the headunit because the amp ground etc is perfectly fine.


----------



## Alrojoca (Oct 5, 2012)

Did you try replacing the RCA s or connect a phone or iPod through the RCA s after disconnecting them from the HU?

Are you testing the HU with a cd or the noise is with every source from the HU ?


----------



## ccapil (Jun 1, 2013)

Noise is with every source, and also with nothing connected just when the car is idelling and gets louder as I rev the engine. Everything is brand new so it can't be faulty equipment.


----------



## qwertydude (Dec 22, 2008)

Who says it can't be faulty equipment even when new? It still could be faulty when new. That's what warranties are for.

If there's noise when the car is on and the amp on and head unit off that's a ground loop. Double check all grounds making sure the amp is well grounded to solid metal, the head unit ground is grounded to solid metal, and just to be sure the head unit chassis is grounded to solid metal.

To test if the ground loop is in the head unit completely disconnect the RCA's and plug an MP3 player into the amp. If it still has noise then the amp might be faulty.

If those are satisfied then I'd begin looking for other sources like in the electrical system.


----------



## ccapil (Jun 1, 2013)

Pretty sure it's not faulty equipment. The noise is present when the car is idalling with the headunit on (aux, USB, tuner etc) BUT the noise goes away when the HU is completly off or on standby. Does this suggest the noise is the headunit, or rcas.


----------



## theeaudioboy (Jun 3, 2011)

ccapil said:


> Pretty sure it's not faulty equipment. The noise is present when the car is idalling with the headunit on (aux, USB, tuner etc) BUT the noise goes away when the HU is completly off or on standby. Does this suggest the noise is the headunit, or rcas.



like suggested by qwertydude ! you need to start by double checking all the Grounds ! then if they are all, to clean metal, then check an make sure RCA cables are Not running by a computer or a power wire !! but then after all checking, its possible of faulty equipment ! but then after all is checked and or fixed, you may need to install a Ground loop isolator ! it will help, but Not fix the existing problem ! its more or less a band aid !!


----------

