Whining noise only when head unit display is dimmed

  • 5
    Participant count
  • Participants list

jsnichols2

CarAudio.com Newbie
8
0
Hi,

I have recently installed a Pioneer AVIC5100 NEX unit in my Jetta. I noticed shortly after install that I was getting a constant high-pitch whine (did not change pitch like alternator noise though) through the speakers at all times. After doing some of the normal troubleshooting steps (see bottom of this post) I researched the Pioneer pico fuse-blowing thing and I think that may be part of the issue. As many suggested, I wrapped bare copper wire around the outside of the radio's RCA outputs and grounded them to the radio chassis and constant whine pretty much went away, although there has been some faint static-sounding intermittent noise in the background when my iPhone is connected via lightning cable for Carplay, and it seems to get a little more active when I'm operating the phone (opening/closing apps, scrolling through pages/settings, etc). Suggestions on this static issue are welcome too. (higher grade lightning cable? Reground radio to car chassis? What am I missing?).

Now the only time I hear the whine noise is when the display is dimmed to any degree, and it's pretty annoying. It seems to be somewhere around the 960-970 hz frequency if I had to guess? It doesn't seem to matter if I have the headlights on to dim or if I manually dim the display through the dimmer settings. I do have my illumination lead hooked to a fuse that only sees 12v when the headlights are on, and I don't think this has anything to do with the issue though. Anyone with a similar problem care to share their experience? I REALLY do not want to go through the whole pico fuse check/repair process if I can help it. Thoughts/suggestions are welcome on this! Thanks!

BTW I have already done the following:

-checked grounds at radio and amps for continuity with DMM (came up 0.00 ohms)

-made sure signal cables and power cables are run apart from each other as much as possible

-checked power leads to radio and amps for proper voltage with DMM

 
Bumpity bump
I have the same issue, although I have a different head unit. I notice that in addition to the parking lights issue that is common to both our setups, that if instead I set the head unit to dim through the navigation app (at sunset), that the same thing occurs.

Did you ever figure this out?
 
PICO FUSE ISSUE. It needs to be repaired more than likely. Though... You may try a hard RESET of the HU to see if that may help first. Yet, I am putting my pennies on the Pico fuse being blown. One of the reasons why I do not run a Pioneer HU, as I swapp amps quite often . There should be an older thread upon the issue and a repair method I believe. You may even check to see if there may be a Firm Ware update possibly
 
PICO FUSE ISSUE. It needs to be repaired more than likely. Though... You may try a hard RESET of the HU to see if that may help first. Yet, I am putting my pennies on the Pico fuse being blown. One of the reasons why I do not run a Pioneer HU, as I swapp amps quite often . There should be an older thread upon the issue and a repair method I believe. You may even check to see if there may be a Firm Ware update possibly
Thank you for your reply. I’m not sure it’s a pico fuse issue as I use a kenwood. Besides, with the pioneer head units, I thought if it was the pico fuse that it’s more of a persistent issue - as in not just when the head unit is dimmed?
 
Did you unplug your RCA's while the HU was powered on?
You can try to ground the outside jacket of the RCA's at the HU to a chassis ground (the closer the better)
 
Last edited:
Did you unplug your RCA's while the HU was powered on?
You can try to ground the outside jacket of the RCA's at the HU to a chassis ground (the closer the better)
I’m not sure how this would be an RCA issue if it only happens when the head unit auto-dims … currently through the NAV-SYNC setting. I would think if there was an RCA grounding issue, I would hear it at all times while the head unit is powered on, correct? Or at least not just when the head unit dims itself.
 
Thank you for your reply. I’m not sure it’s a pico fuse issue as I use a kenwood. Besides, with the pioneer head units, I thought if it was the pico fuse that it’s more of a persistent issue - as in not just when the head unit is dimmed?
For Kenwood.. as I use other than my Eclipse units.. I found that it was a Firmware issue with a 900 series. You can call Kenwood and they can email you the download. there has been an issue with a setof bad RCAs in the past that I ended up wrapping the connections of which helped till changing out to Zero Noise Stinger of which I only use now. you may try a Reset on the HU before doing anything.. if the issue continues, Id try the firmware process
 
For Kenwood.. as I use other than my Eclipse units.. I found that it was a Firmware issue with a 900 series. You can call Kenwood and they can email you the download. there has been an issue with a setof bad RCAs in the past that I ended up wrapping the connections of which helped till changing out to Zero Noise Stinger of which I only use now. you may try a Reset on the HU before doing anything.. if the issue continues, Id try the firmware process
An update. I bench tested the kenwood unit with another amplifier, a different set of speakers, and another set of RCA’s. After directly connecting the speakers without using the new amplifier in this bench test, there was no hum with the screen dimmer on. However, when using the new amplifier in this bench test, the hum was again there with the dimmer turned on, but gone with the dimmer off. I will also note that the illumination wire wasn’t connected in this setup.

So with two different setups and completely different equipment (except for the head unit), the hum is present in the exact same way. Is there something wrong with the head unit? Should I get Kenwood to start an RMA?
 
An update. I bench tested the kenwood unit with another amplifier, a different set of speakers, and another set of RCA’s. After directly connecting the speakers without using the new amplifier in this bench test, there was no hum with the screen dimmer on. However, when using the new amplifier in this bench test, the hum was again there with the dimmer turned on, but gone with the dimmer off. I will also note that the illumination wire wasn’t connected in this setup.

So with two different setups and completely different equipment (except for the head unit), the hum is present in the exact same way. Is there something wrong with the head unit? Should I get Kenwood to start an RMA?
If its under Warranty and you still have the box and contents it came it.. Id return it as a defective unit
 
If its under Warranty and you still have the box and contents it came it.. Id return it as a defective unit

I do still have the warranty. The headunit is a DNR1007XR, so it’s pretty new. I’m sending it in for service, but I’m just hoping they don’t send it right back and say everything’s fine. The technician on the phone seemed to think the issue was an RCA cable, even after I explained how I performed the bench test.

Then he wanted me to test just a single speaker hooked up, bypassing the amplifier … implying that it was the amplifier. He was kind of missing the point. If you’ve used two different sets of amplifiers, cables, and speakers, but the issue persists through the RCA jacks with the same head unit, then you have no where else to go but the head unit.

I’m mailing it in Monday, along with a detailed write up, pictures, and a DVD video demonstrating the issue. I’m hoping they diagnose it properly, but since I have no access to the people performing the testing, coupled with the fact that companies nowadays seem to be completely dismissive of user input, my hopes are kind of low.
 
Activity
No one is currently typing a reply...

Similar threads

I'm getting a whining noise from my one speaker anytime something in the truck activates. When lights are triggered to turn on. Happens when the...
0
622
You just found your own solution. Move the DSP elsewhere. The RCA is triple protected but not the RCA plugs. I do not know if there is a mesh or...
1
422
Disconnect the RCA's or hi-level input to the JBl amp. turn the system on, If the noise continues, it's a ground or noise issue with the amp.If it...
1
353
Yes i know that's what i was planning on. Unfortunately the rvca's are a little difficult to gain access to. My other thought was to wrap a wire...
2
1K

About this thread

jsnichols2

CarAudio.com Newbie
Thread starter
jsnichols2
Joined
Location
Start date
Participants
Who Replied
Replies
11
Views
2,223
Last reply date
Last reply from
Popwarhomie
1000006564.jpg

Mr FaceCaser

    Mar 28, 2024
  • 0
  • 0
1000006569.jpg

Mr FaceCaser

    Mar 28, 2024
  • 0
  • 0

Latest topics

Top