Hissing Noise Coming from Speaker

[ugadawgs311]

I have a Pioneer AVIC-D3 installed in my 2003 Z71 Tahoe. It's been installed for over 2 years now and I've had minimal problems with it. However, yesterday I noticed a high pitched whining sound coming from the front left tweeter. The hiss is only there when the engine is on. In other words, if I just have the head unit on, there is no hiss. Also, when I accelerate I can hear the hiss get higher and higher as the RPM's increase. It happens when I listen to CD's, my iPod, the radio, etc. Any ideas on what could be causing this and how to fix it? Thanks!

[dustpuppy]

Alternator whine.

 

What is your setup? (amps etc.)

 

Any abnormal cargo/passengers that could have bumped something and messed up a ground? I need to send my old D3 in for repairs after some wire-giggling on another unit did something to the RCA ground on the deck

 

-Ernie

[ugadawgs311]

Well I have the AVIC-D3 hooked up to my factory Bose system. So I'm not exactly sure what my setup is like. I've been told the ground is probably the issue. Any idea on how to find the ground and what to do with it when I find it?

[dustpuppy]

*faints, then twitches*

 

I *hated* my bose; it was like a CANCER that took a month to initially cut it out. I assume you're using something like a PAC module or similar to revert to an appropriate line level; if you haven't touched anything, it's hard to know what went wrong.

 

It could be as simple as pulling the fuse to the radio (I mean the factory fuse that powers the amp) for a few hours, forcing it to re-initialize or if the original setup somehow went out, you may need to replace it (like the PAC module).

 

Who did the install initially?

Do you have any changes to your system recently?

 

One thing you can try is re-grounding the RCAs that come out of the back of your deck (if you're using them) --- it's sort of a hack, but it will fix some grounding issues. All you do for that is wrap unshielded wire (strip like 3 inches off the end of a wire) around the metal over the RCA, then tape over the top of that, then run the wire to ground.

 

Good luck.

 

-Ernie

[ugadawgs311]

Thanks for the help. I did the install initially. I did it over 2 years ago though and haven't had any issues with the head unit since then. This just all the sudden happened one morning when I got into my car. I haven't changed or modified any part of the system since the initial install. I hope it's not something internal with the head unit.

[ugadawgs311]

Thanks for the advice. Before I cracked open the dash, I decided to remove the fuse for the radio for about a minute, then I put it back and it worked! The hissing noise is gone and everything seems to be back to normal. Thanks for telling me to try that first- it saved me a lot of time.

[dustpuppy]

Cool. Some residual charge was built up somewhere along the line.

 

Hunting a grounding issue is OK if it was something you didn't do right, but faulty electronics take forever to figure out. Alternator noise is worse because a bench test is out of the question.

 

Glad you're fixed!