Getting a LOT of electrical noise through the radio. Ideas?

[Big Top Gt]

I'm getting a little annoyed by how much electrical "whining" I'm getting through the radio.

Has anyone come across this issue and if so, what have you done to resolve it?

It gets even worse when I turn on the headlights.

It's driving me crazy!

Thanks,
Alan

 

[bigastrk]

Is it the stock radio setup?

 

[Freaknazty]

first thing that i always found to cause this is a bad ground ....

 

[MikeVistaBlue06]

I'm getting a little annoyed by how much electrical "whining" I'm getting through the radio.

Has anyone come across this issue and if so, what have you done to resolve it?

It gets even worse when I turn on the headlights.

It's driving me crazy!

Thanks,
Alan

If you have an aftermarket radio and/or an aftermarket radio antenna, unplug the antenna connection because that is probably the source of your ground loop causing the whine. Just ask Doc if you don't believe me!

You can also put some large electrolytic capacitors across all of the incoming power supply lines to ground to shunt high frequency AC signals to ground.

Hope this helps.

Mike

 

[KIMMER]

What they said. Another thing is spark plugs, I know, sounds dumb, but they make resistor plugs and nonresistor. When I had my 68 camaro and had the non's in it, the whine was unbelievable!

 

[Androdz]

do you have hid's in the car? A bad ballast can cause interference.

 

[Big Top Gt]

I've got a Pioneer AVIC Z1 nav unit in the car.

I'll unplug the antenna tomorrow and see what I get. Otherwise, I have no idea where to even START looking for bad grounds. This car has so much crap in it that's wired in it's not even funny.

I don't have HID's.

 

[Hawgman]

That antenna thing will piss ya right the fuck off.

Mike and I spent the better part of an afternoon and evening redoing every single ground in the damn cabin of the car. Large gauge wiring, direct off the battery, every fucking connection soldered. No noise when the radio was not mounted. Mount it, instant noise. Isolated the mount points, still same scenario. Then got to thinking.. what is different when the radio is not mounted. The antenna isn't plugged in. Reached in and unplugged the antenna and the noise went away. ARGH!!! Oh well, never have it on terrestrial radio anyway. That is what Sirius is for Shit if I could get the hole in the fender filled in and repainted for cheap I wouldn't even have an antenna anymore.

 

[TexasBlownV8]

Typically, whine in the radio is caused by AC getting in the power, usually caused or produced from the alternator (at it generates AC [alternating current] and mostly converts it to DC). If it would be popping noises, that's usually plugs or more likely unshielded plug wires.

Usually, a capacitor near the source of the noise solves the problem. You can also put one on the line providing power to the device showing symptoms, like the radio.
If ANYTHING was changed and is not stock, including the radio or alternator, or if someone removed a noise suppression capacitor, you could hear whine in the radio, and possibly see flickering in the lights, too.

This used to be a bigger problem in older cars with external voltage regulators and capacitors. A lot of things have appropriate filtering built in now, especially stock items.

 

[MikeVistaBlue06]

Typically, whine in the radio is caused by AC getting in the power, usually caused or produced from the alternator (at it generates AC [alternating current] and mostly converts it to DC). If it would be popping noises, that's usually plugs or more likely unshielded plug wires.

Usually, a capacitor near the source of the noise solves the problem. You can also put one on the line providing power to the device showing symptoms, like the radio.
If ANYTHING was changed and is not stock, including the radio or alternator, or if someone removed a noise suppression capacitor, you could hear whine in the radio, and possibly see flickering in the lights, too.

This used to be a bigger problem in older cars with external voltage regulators and capacitors. A lot of things have appropriate filtering built in now, especially stock items.

The first thing we did was put caps across all power in and it helped some, but not entirely. The antenna was a big ground loop and that stopped it when we unplugged it.

Mike

 

[Big Top Gt]

I'm walking out to the garage now to unplug the antenna.

I'm thinking that maybe I should solder all the lines to a lug and connect it directly to the block.

 

[Big Top Gt]

Well, pulling the antenna didn't resolve the issue. :/

I'm going to start collecting grounds later this week and bolt them to the block. Hopefully that'll help.

The worst sound comes when I turn on the headlights. Is there some kind of line conditioner I can run in the wire from the lights to the dimmer in the radio?

 

[MikeVistaBlue06]

I'm walking out to the garage now to unplug the antenna.

I'm thinking that maybe I should solder all the lines to a lug and connect it directly to the block.

Run a single ground line from the ground post of your battery and put all of your grounds on this one.

Hope this helps.

Mike

 

[MikeVistaBlue06]

Well, pulling the antenna didn't resolve the issue. :/

I'm going to start collecting grounds later this week and bolt them to the block. Hopefully that'll help.

The worst sound comes when I turn on the headlights. Is there some kind of line conditioner I can run in the wire from the lights to the dimmer in the radio?

Put an electrolytic capacitor (as big as you can find that is rated at 12V or higher) on the wire coming from the dimmer (+ side of cap on dimmer wire), and ground the other end, and that should shunt any AC noise to ground from the dimmer wire.

Hope this helps.

Mike

 

[tom281]

I've had various head units including a AVIC D3 lately along with several amps and components and have had no noise at all until one day it just showed up, not huge but noticeable. About a week or two later I started getting a 3040 code, and about a month after that the alternator was dead......

Mike is def right about ground loops and their potential to cause noise in various locations, but don't forget the alternators in these cars are pretty much junk.

 

[Big Top Gt]

The alternator seems to be charging fine. Maybe I can take it to PepBoys this week for one of their charging system checks. (20 bucks.. can't beat it.)

Thanks Mike. I'll see if I can pick up an electrolytic capacitor asap. Any idea how much it should run me?

I'll also look at running one wire to the battery for a solid ground. Any suggestions as to what kind of ring or connection setup to use?

 

[TexasBlownV8]

Big Top, just re-read and see that you have a different radio and on hids.

FWIW, larger capacitors will not help you; the larger the capacitor, the lower the A/C frequency that will get filtered; that would be more of a lower-pitched sounds than higher-pithed whining. A cap like .1 uF may help, and will be much cheaper.

Here's what I would try: get like a CB radio or similar 'noise suppression kit' like from a radio shack or somewhere. It will have a coil and capacitor. The coil/cap combination should reduce the whining.

chasing ground loops and other such issues in the stock wiring, assuming all else is stock, is potentially worthless. Notwithstanding, the ground of your radio needs to be the same as the power filter ground to avoid ground loop voltages. Actually, make sure the radio HAS a GOOD ground itself!

You shouldn't be hearing any noise at all.

 

[Big Top Gt]

Anyone want a free lunch?

Stop by my house and help me clean up this mess. Next time I have the dash apart I'll snap a picture of the rats nest of wires left behind by the installer.

Holy crap are there a lot of wires mashed up in here.

Thanks for the advice Mike. I'll check into it today.

 

[MikeVistaBlue06]

FWIW, larger capacitors will not help you; the larger the capacitor, the lower the A/C frequency that will get filtered; that would be more of a lower-pitched sounds than higher-pithed whining. A cap like .1 uF may help, and will be much cheaper.

I disagree with your comments and the physics/electrical engineering of the situation also disagree with what you say.

Capacitive reactance (impedance to an AC signal) is as follows:

Xc = 1/(2*pi*f*C)

Therefore, Xc gets smaller when both f and C are large. The smaller Xc is, then the better it can shunt unwanted AC signals to ground. You build what is basically called a low pass filter where the higher frequencies are shunted to ground and only the lower frequencies pass. That means you use the largest capacitor you can find to send as much of the higher frequencies to ground.

If you look at what they do to provide passive crossovers using capacitors, you can see how the larger capacitors let more signal through.

Given Xc = 4 ohms for speaker then,

f = 1/(2*pi*4*C)

so as C gets bigger f gets smaller, so this means that the larger the capacitor the more of the AC signal bandwidth can pass through to ground.

Here is a good reference describing what I am talking about:

http://en.wikipedia.org/wiki/Low-pass_filter

BTW, I made straight A's in these subjects while in college.... Big Top, get the LARGEST capacitor you can find for the purpose of shunting noise to ground. You should be able to get a 2200µF electrolytic cap rated at 12V or higher at Fry's or Radio Shack for about $3 at most.

Hope this helps.

Mike

 

[Big Top Gt]

Nothing is better than part numbers.

I'll pick one up and report back later.

You guys are the best.

Oh, and here's what you're dealing with:

I'll get pics of the rats nest later.

You all need to move to south florida. HA!