alternator whine / AUX input / electrical humming
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alternator whine / AUX input / electrical humming
05-10-2005, 07:46 PM #95
05-10-2005, 09:08 PM #96
05-10-2005, 10:12 PM #97
05-10-2005, 10:17 PM #98
05-11-2005, 06:38 AM #99
05-11-2005, 06:41 AM #100
05-11-2005, 10:13 AM #101
05-11-2005, 10:22 AM #102
05-11-2005, 12:18 PM #103
Today, 07:00 AM #104
I just started noticing this humming whine when I turn up the volume really loud, and the car is moving over 80 mph. It is annoying !
inFiniTE LooP,
Can you tell me more about the GROUND LOOP ISOLATOR ? Where do you get it ? how do you install ? ????
Perhaps Scorchie or Steve (MBenzNL) could also provide any suggestions, as to the grounding of COMAND units, in order to prevent AUX input electrical humming.
Carlos
Saprissa@aol.com
Originally Posted by ctC230K
i have a problem with my aux cable. i am getting an electrical hum from the s/c interfering on the aux channel.
Originally Posted by CarlsbadKmprssr
Are you sure the noise is from the sc? Usually that interference comes from things like the alternator.
Originally Posted by nlpamg
woah, (knock on wood), but I've never had interference problems. do you guys have the standard sound system or h/k? could it be the source of the audio (e.g. mp3 player) taking the interference and NOT the aux?
Originally Posted by inFiniTE LooP
usually 'alternator whine' occurs with the installation of aftermarket stereo parts, it's rare that a car will ship out with this happening, i know i never had any alternator whine until i installed XM, but i got rid of it with a ground loop isolator
Originally Posted by ctC230K
the only "after market" part which was really an OEM part I added was the Aux Cable, it probably is an alternator hum but IDK. I can actually switch to Aux Input and without anything connected to it, turn the stereo up and listen to my car's engine speed over the speakers hahaha, it's fun for about 2 minutes until the hum drives you crazy!
Originally Posted by Jim Banville
Nothing is connected to the cable?
Originally Posted by ctC230K
well i connect either my Ipod or my Sirius but even if i disconnect them, and just let the cable hang there, then I turn the volume up i hear my engine speed humming lol!!
Originally Posted by Jim Banville
Try removing the cable and see if the alternator whine goes away. If it does, you may have a defective cable.
Originally Posted by Capt Nemo o2
It could also just be how he put the wire back in the door sill. If there is a sizeable section running close and parallel to any high current wire it will be affected by the magnetic field created by the current running through the wire. That is usually one of the biggest problems with high powered stereo systems. The cable running from the battery to the amp very often is run near and parallel to the speaker wires causing that hum.
Originally Posted by ctC230K
ok but explain this: the aux cable has been in that same position for two months now, this interference humming only started in the last two weeks!! i haven't moved the cable or hooked up any different devices! i get the hum on everything on the Aux Input, weather nothing is hooked up to the cable, if i plug in the ipod, sirius, my cell phone, whatever.should i start a new thread? it's getting really annoying to hear a hum in the background of everything on the aux input.
inFiniTE LooP,
Can you tell me more about the GROUND LOOP ISOLATOR ? Where do you get it ? how do you install ? ????
Perhaps Scorchie or Steve (MBenzNL) could also provide any suggestions, as to the grounding of COMAND units, in order to prevent AUX input electrical humming.
Carlos
Saprissa@aol.com
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From: 38° 52′ 51″ N || 94° 48′ 11″ W
'01 C320 || '14 Honda Pilot EX-L
I get wicked noise over my aux when using my XM radio, but when the Dell DJ is connected it is very quiet. I think that I may go back to FM transmission for my XM. I personally don't feel that it is the COMAND in my case.
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From: Irvine, CA, USA
Tesla
Ground loop isolator can be purchased at radio shack or electronic shops. It's basically an inline filter between your source wires to eliminate ground loop. Ground loop occurs when there are impedance between different ground points in the car. For example, if your headunit is grounted to the front of the car chasis while the amp is grounded to the back of the chasis, the front to back chasis conductivity might not be "pure" thus causing difference in grounding impedance, resulting in the humming effect.
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From: Hawaii
2005 Volvo S40 T5 AWD, 2004.5 C230 Sport Sedan, 2005 E320 CDI, 2008 C300 4-Matic Luxury
just took this from the other thread:
Originally Posted by inFiniTE LooP
the ground loop isolator basically just takes away the ground from BETWEEN the stereo and other audio component (ie-XM radio or AUX port). i got mine from circuit city, it should just plug directly from whatever the source is, and recreate the jacks on the other side, it's just a "go between" guy, just like a coupler in that sense.
so if on the back of the radio there are 2 female ends to plug things in, you plug the ground loop isolator in, and on the other end of the box of the ground loop isolator is another set of females to plug your AUX cable into.
so if on the back of the radio there are 2 female ends to plug things in, you plug the ground loop isolator in, and on the other end of the box of the ground loop isolator is another set of females to plug your AUX cable into.
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excites your girlfriend
Update: I've figured out where the noise is coming from. The cigarette lighter in the front console. I pulled up my aux cable and unplugged the stereo plug extension cable that ran from the MB aux cable to the Sirius and the sound was gone. Then I plugged it back in and the sound came back. First I thought it was the headphone jack extension cable because i had it coiled up and thrown under the seat but that wasn't it. I unplugged the Sirius cigarette lighter adapter and the sound was gone. Then I could plug it into the rear cigarette lighter socket and there was no hum! How come only the front cigarette lighter hums?? What should I do? Rewire it to the rear cigarette lighter? That would suck. Would this ground loop isolator help me? 
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From: Hawaii
2005 Volvo S40 T5 AWD, 2004.5 C230 Sport Sedan, 2005 E320 CDI, 2008 C300 4-Matic Luxury
interesting, it could be that there is a bigger difference in resistance between your front cig. lighter and rear one thereby only having the front one having this effect. if this is the case, then the ground loop isolator will fix your problem. if it doesn't fix your problem, then simply return the product and say it didn't work, they're cheap anyway, only about $16
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From: Connecticut
excites your girlfriend
thanks. i'm gonna see if i can get one today. i also want a 24" gold plated headphone jack to headphone jack cable, maybe monster cable makes one. that should cut down on some of the crap coming in through that line.
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From: SFV, CA
2004 CLK500, 78 6.9,
um, gold headphone jacks will make absolutely NO difference with alternator whine or ground loops. Think about it. Your audio signal will go through some beefy cable, then into a jack, where the connection isn't soldered, its just a friction hold... then it goes into tiny unshielded wires behind the glovebox and into the radio, where its surrounded by all different voltages and impedences, and probably some magnetic fields.. and in the radio, its just lines on a circuit board..
I never understood this whole giant gold cable mumbo-jumbo...its never been proven to have any positive effect on sound quality.
I never understood this whole giant gold cable mumbo-jumbo...its never been proven to have any positive effect on sound quality.
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From: San Francisco Bay Area
2003 SL500
Originally Posted by ctC230K
Update: I've figured out where the noise is coming from. The cigarette lighter in the front console.
Hmm. Wonder if the COMAND inputs and lighter plugs are on different grounding circuits, and if so why. I know I've got two batteries, but I thought everything except the starter was on one circuit.
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From: SFV, CA
2004 CLK500, 78 6.9,
OK, I had the same problem with my aux input. When I played sound through my ipod, it was fine.. until I plugged it into the cigarette lighter, then the alternator whine took over, obviously a ground loop. I have since installed a Sirius receiver into this aux input, which needs a constant power source, since it isn't battery powered. The way I got rid of the whine is a bit more complicated, but it's the best solution, I think. I didn't get my power from the lighter at all.. I tapped into the power at the Bose amplifier in the trunk, and ran a regular 16guage speaker cable from the amp's positive and negative power leads to the power of the Sirius. No noise at all, now.
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From: Irvine, CA, USA
Tesla
Hum from cigarette lighter is a good indication of ground loop. Just go to your local car stereo shop or radio shack and get a ground loop isolator (GLI) and connect it in between the AUX jack and your IPOD. You might need some adaptor for the right jack since most GLI comes with dual RCA plugs.
Here's the one from RatShack:
http://www.radioshack.com/product.as...t%5Fid=270-054
Here's the one from RatShack:
http://www.radioshack.com/product.as...t%5Fid=270-054
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From: SFV, CA
2004 CLK500, 78 6.9,
This thing is just a bandaid to the problem, if it works at all...
Originally Posted by steph280
Hum from cigarette lighter is a good indication of ground loop. Just go to your local car stereo shop or radio shack and get a ground loop isolator (GLI) and connect it in between the AUX jack and your IPOD. You might need some adaptor for the right jack since most GLI comes with dual RCA plugs.
Here's the one from RatShack:
http://www.radioshack.com/product.as...t%5Fid=270-054
Here's the one from RatShack:
http://www.radioshack.com/product.as...t%5Fid=270-054
Senior Member
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Posts: 491
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From: Irvine, CA, USA
Tesla
bandaid or not, it is commonly used by stereo shops for installs. Some even put them in regardless if they have hums.
Some go to the extreme of installing a heavy duty ground wire across the car so all audio equipment have the same ground point. Being as complicated MB's already are, I would shy away from such mods.
Some go to the extreme of installing a heavy duty ground wire across the car so all audio equipment have the same ground point. Being as complicated MB's already are, I would shy away from such mods.
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From: Sindelfingen, Germany
E350CDI S212, MY2011
Ground Loop - Electrical Humming
Hi,
your problems should only exist while using the cigarette lighter for power supply of external audio equipment, which is connected to the Aux-In-Jack in the glovebox.
The problem can be solved by deleting the connection between shield and ground of the harness A 203 540 61 07 (the Aux-In-Harness).
With a stock Comand system, there is the Aux-In-jack in the glovebox. The wiring to the Aux-In-jack has a connection shield<->ground (connection between mesh network and brown wire) near the jack. If you CAREFULLY remove the isolation about 1" from the jack, about 1/2" wide, you will find the shield (mesh network). If you ALSO CAREFULLY cut this shield around the wires and remove it completely, afterwards use adhesive tape for the isolation, your problem is solved.
If you can wait until December 2005 or January 2006, you can get a new wiring harness (successor for the A 203 540 61 07) at your local MB dealer.
your problems should only exist while using the cigarette lighter for power supply of external audio equipment, which is connected to the Aux-In-Jack in the glovebox.
The problem can be solved by deleting the connection between shield and ground of the harness A 203 540 61 07 (the Aux-In-Harness).
With a stock Comand system, there is the Aux-In-jack in the glovebox. The wiring to the Aux-In-jack has a connection shield<->ground (connection between mesh network and brown wire) near the jack. If you CAREFULLY remove the isolation about 1" from the jack, about 1/2" wide, you will find the shield (mesh network). If you ALSO CAREFULLY cut this shield around the wires and remove it completely, afterwards use adhesive tape for the isolation, your problem is solved.
If you can wait until December 2005 or January 2006, you can get a new wiring harness (successor for the A 203 540 61 07) at your local MB dealer.
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excites your girlfriend
Problem Solved
Update #2: Thanks guys, I bought a ground loop isolator from Radio Shack this weekend ($15) solved all my humming problems. Also it actually replaces the headphone jack to headphone jack cable i was using and it is gold plated too! lol i'm not sure if that helps buy why not. now i just need to figure out where to hide it, it's the size of a D battery and looks funny hanging between my Sirius and Aux Cable Harness.
Now my next problem- I turn the radio up as loud as it goes and sometimes I still want it to go louder. Maybe the Sirius doesn't put out enough volume but I think the problem is the head unit limiting what it sends to the stock speakers so I don't blow them.
No one wants to touch my audio system because it's all fiber optics and they claim they can kill the whole system if they short out one cable by accident and it's too much of a liability.
Now my next problem- I turn the radio up as loud as it goes and sometimes I still want it to go louder. Maybe the Sirius doesn't put out enough volume but I think the problem is the head unit limiting what it sends to the stock speakers so I don't blow them.
No one wants to touch my audio system because it's all fiber optics and they claim they can kill the whole system if they short out one cable by accident and it's too much of a liability.
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From: Hawaii
2005 Volvo S40 T5 AWD, 2004.5 C230 Sport Sedan, 2005 E320 CDI, 2008 C300 4-Matic Luxury
does your Sirius have it's own internal volume setting, may wanna check the manual for it as most sattelite radio units have some kind of internal volume setting of their own
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excites your girlfriend
yes, it has a volume button on the side, i made sure it's turned all the way up. if i turn the volume on the stereo up to about 90% and have the bass and treble on their max settings, going past 90% only makes the mid tones louder, the bass and treble stay at a 90% max level. i think that happens because the speakers are maxed out and only the mid tones can be increased, has anyone else noticed that?
Thread Starter
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From: San Diego, CA & San Jose, Costa Rica & Stuttgart, Germany
1959 220S / 1979 230 G / 2002 A210 AMG / 2003 C320 SC / 2004.5 C320 SS / 2005 ML350 SE / 2008 smart
Originally Posted by cc4469
If you can wait until December 2005 or January 2006, you can get a new wiring harness (successor for the A 203 540 61 07) at your local MB dealer.
Thanks !I'll try the $15 ground loop isolator first, and then get the new MB wiring harness when it comes out.
Carlos
Saprissa@aol.com
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Originally Posted by ctC230K
Update #2: Thanks guys, I bought a ground loop isolator from Radio Shack this weekend ($15) solved all my humming problems. Also it actually replaces the headphone jack to headphone jack cable i was using and it is gold plated too! lol i'm not sure if that helps buy why not. now i just need to figure out where to hide it, it's the size of a D battery and looks funny hanging between my Sirius and Aux Cable Harness.....
Thx!
Last edited by spanky; Nov 10, 2005 at 10:07 PM.
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From: Gadsden, Alabama
'06 C350 4MATIC
Ground Loop Isolators
Originally Posted by spanky
Do you by any chance have the part number of the filter? I tried searching for it online and was unable to.Thx!
http://mcm.newark.com/NewarkWebComme...SKU=60-405&N=0
http://www.radioshack.com/product/index.jsp?productId=2062214&cp
http://www.audioxpress.com/reviews/media/AE600HA.pdf
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Originally Posted by Tishers
