Batboard

Any ideas on getting rid of what sounds to be alternator or fuel pump whine in a 2005 Crown Vic Sport?

I installed an Icom 208H radio and ran 6ga wires from the trunk directly to the battery. I get a high pitched whine sound from the remote speaker as I rev the engine or accelerate. I've tried grounding the radio in the trunk, grounding the trunk deck lid, and also tried a heavy-duty DC line noise filter from these folks: http://www.powerwerx.com/category.asp?CtgID=1849

Still has the irritating whine sound, even with the filter.

Some Pics of the install here: http://www.cardomain.com/ride/2040296

Appreciate any help you might provide.

-Make sure the NMO mount is grounded very well to bare metal on the inside of the decklid.

-Be sure that you have a solid ground from the decklid to the chassis...a 1/4" or larger ground strap works best.

-Do not ground the radio to the battery or any existing OEM grounds in the trunk. Make a seperate ground on the vertical support by the left trunk hinge. The shorter the ground, the better. Use a 1/4-20x1" bolt that is double-nutted thru the support and attach your ground to that. Be sure to remove the paint from both side of the hole, to ensure a solid ground.

I see that the radio is grounded to the battery...this is not the best way to go, and you should change that immediately if not sooner. If the ground is fused, remove that also. There is no need for the ground to be fused, and it poses a safety risk. If the ground fuse fails, and the OEM grounds are compromised, then the electrical system will try and ground the entire car thru your 208's chassis and fry your radio...creating a lot of smoke in the process, and very possibly sparks/fire.

Try these things and report back.

i believe one of the other popular fixes to this problem was an attenuation capacitor across the fuel pump powersources.

Alternator whine is also a symptom of a bad ground connection at the battery or a failing alternator. If some diodes are bad in the alternator, the thing will still charge the battery, but failure will be imminent and sudden.

Alternator whine varies with engine speed.

007 wrote:-Make sure the NMO mount is grounded very well to bare metal on the inside of the decklid.

-Be sure that you have a solid ground from the decklid to the chassis...a 1/4" or larger ground strap works best.

-Do not ground the radio to the battery or any existing OEM grounds in the trunk. Make a seperate ground on the vertical support by the left trunk hinge. The shorter the ground, the better. Use a 1/4-20x1" bolt that is double-nutted thru the support and attach your ground to that. Be sure to remove the paint from both side of the hole, to ensure a solid ground.

I see that the radio is grounded to the battery...this is not the best way to go, and you should change that immediately if not sooner. If the ground is fused, remove that also. There is no need for the ground to be fused, and it poses a safety risk. If the ground fuse fails, and the OEM grounds are compromised, then the electrical system will try and ground the entire car thru your 208's chassis and fry your radio...creating a lot of smoke in the process, and very possibly sparks/fire.

Try these things and report back.

Could you explain your theory on the whole ground issue again? I don't get what your saying. You say if the ground side fuse is blown and the OEM grounds go bad that the entire system will try to ground through the radio? How?

Since the positive side is fused if any extra current were to flow through the radio from a failure of the vehicle wiring, that is if the radio is even mounted in such a way that it's grounded directly, the positive lead fuse will blow before damaging the radio. Also, i have seen plenty of installs where the ground failed and the radio was grounded through the coax to the antenna mount. Still, the positive lead fuse will blow preventing damage.

As for what i have seen, if the ground to the engine block or body fails, most modern vehicles have a heavy gauge lead to the engine block and a smaller gauge lead to the inner fender near the battery, then everything will try to pull through the radio if its connected to the battery for ground, which is prevented from happening by the fuse! So if the OEM grounds fail and the fuse fails, in your analogy, then nothing works since the entire electrical system is now disabled. Again, if it now tries to seek out a ground the radio will be protected by the fuse in the positive lead which will pop in short order if this happens, i know because i have seen it happen!

There seems to be a big difference from Amateur equipment and commercial. The Amateur gear always has a fuse holder in the ground side, this is mainly because the manuals also suggest connecting directly to the battery, so the negative lead needs to be fused to prevent damage. Where as the commercial gear never has a fuse in the negative side because the common practice is to install them completely permanent and in such a way that the radio ground is made to the body or chassis near the radio install.

Again, think of "temporary", most Amateur band radios are made this way because some hams move them from vehicle to vehicle, and they don't bolt em down and make it dead permanent.

Now, if he wants to change the way it's installed, he should cut the ground wire back at the radio and go to the body of the vehicle as suggested, then he can eliminate the fuse because its no longer connected to the battery. But, the way he has it is fine as long as the negative lead is fused. However, i hardly install them that way anymore since its easier to pull one wire for power rather than two to make the ground connection at the battery as well. But this is still common practice for the Amateur products because of the design of the power cords, and the manuals showing to install this way.

thebigphish wrote:i believe one of the other popular fixes to this problem was an attenuation capacitor across the fuel pump powersources.

I have been there and done that on plenty of older Ford's. You used to be able to go to the dealer and buy a kit with everything needed to eliminate the fuel pump noise.

On the newer vehicles, his being a 2005, the local dealership says that this is no longer available or needed. I don't know that for sure since i have yet to work on anything past a late 90's or early 00's, so maybe someone else can comment on that if they have done an 05.

I would bet his problem is alternator whine. I suggest removing the ground wire you ran back to the trunk and grounding the radio to the body of the vehicle at the mounting location. You might be getting whine from all the extra ground wire. I had a Icom IC-2000H that did that, if you ran the ground to the battery as the manufacturer suggests it would pick up noise from the engine compartment like crazy. I just clipped the ground about a foot from the power cord side of the connector that the radio plugs into and seperated the wires, its easy since its just heavy duty zip cord, and then grounded to the body of the vehicle and removed the rest of the ground wire and fuse that would normally lead out to the battery.

Now i suggest this because you mentioned grounding the radio in the trunk, but you didn't tell us how you accomplished that.

If you don't want to chop up the stock cable just get some connectors, the T-type connector that the radio uses is easily available for a few bucks from BuxCommCo and then you can make a custom power cable and toss the stock one back in the box in case you ever sell the radio.

I suspect that after you redo the ground you won't even need that noise filter. If after doing all this you still have a noise problem then make sure the antenna mount is well grounded where it goes through the trunk lid. If that still doesn't work take the car back to the dealer and tell them you want the alternator checked/replaced, the newer ones shouldn't be making that much noise!

When I installed the NMO mount, I scraped the underside of the hole to ensure good contact with metal. Additionally, although my pics don't show it, shortly after doing the install I ran ground braid from the trunk deck lid to the vehicle chassis too. Today, I tried disconnecting the ground lead at the battery, cutting the wire in the trunk and bolted it to the vehicle chassis as well. Still got the silly whine, which does indeed vary with engine speed. I also tried disconnecting the antenna by removing the PL-259 off the radio. No help.

So... maybe it is a defective alternator. It's a brand new car, but I guess stranger things have happened.

Before I go to the dealer and attempt to get them to replace the alternator, I'd like to try installing the capacitor. Anybody know what value to use and perhaps provide a little insight as to installation? Thanks.

stevereno wrote:
So... maybe it is a defective alternator. It's a brand new car, but I guess stranger things have happened.

Before I go to the dealer and attempt to get them to replace the alternator, I'd like to try installing the capacitor. Anybody know what value to use and perhaps provide a little insight as to installation? Thanks.

Try to get the alternator first, before you add the cap...it the tech looks at the fuel pump wires and sees the cap, your warranty means exactly dick at that point...they will deny the claim most likely.

We got a brand-new F-150 SuperCrew that promptly ate three alternators. Fourth time around, we actually got one that was worth a damn and didn't whine. Unfortunately, Ford's alternators aren't what they once were. Don't discount a bad alternator as a possibility.

And be prepared for a fight. Most likely, your alternator will "load test" OK. That means exactly dick when it comes to the *quality* of the DC. Trying to explain an o-scope, waveforms, what DC should look like, etc. to a "technicial" is almost always a futile effort.

007 wrote:

stevereno wrote:
So... maybe it is a defective alternator. It's a brand new car, but I guess stranger things have happened.

Before I go to the dealer and attempt to get them to replace the alternator, I'd like to try installing the capacitor. Anybody know what value to use and perhaps provide a little insight as to installation? Thanks.

Try to get the alternator first, before you add the cap...it the tech looks at the fuel pump wires and sees the cap, your warranty means exactly dick at that point...they will deny the claim most likely.

My vote goes this way as well.... 90% of the time it's a bad alternator if you've checked your grounds.

Speaking of which, I did an install the other week in a 2005 vic and this week they're reporting "hum". Of course the hum could be alternator whine but I am not sure. I'll report back here with what I find. This one has a CDM1250 in it.

Power cable is run to the power tap point on the fuse block. Ground is grounded to the factory ground points in the passenger kick panel.

Kurt