Question for you I.C.E. experts

[H5V VE]

So,

I have recently had a cog drive fitted to my s/c and it has now manifested a rather unexpected problem.

Whenever I plug a lead into the front aux socket of the stereo, it immediately picks up the sound of the s/c and starts amplifying it through the speakers. Its a bit like the old 70's car radio when you didnt have the right suppressor put in and you get hear it everytime that you accelerated.

To pre-empt the obvious comments, I dont necessarily have a problem with this but Mrs H5VVE is distinctly unimpressed since it plays havoc with the ipod and with a long overnighter down to the south of France coming up soon, I really need to find a solution.

Anyone got any ideas on what can be done to supress that level of noise/interference?

[ARAF]

I think you've already given the answer yourself.

If it's just through the front port, then take a little time to put an extension lead in the rear aux socket. If it's both that are doing it, and it's as soon as you plug a lead in the socket, then you need to shroud the lead to stop it picking up the interference, or shroud the point of interference.

Personally, I don't think it's the cog drive as I can't think of an electrical circuit there. However, as the cog noise matches the engine revs, it will sound as if that's what it's picking up. More likely to be a coil or HT lead, I would have thought.

[Gary H 2008]

Noise cancelling headphones for your wife

Seriously. Been there done that, replaced and beefed up all the Earthing straps, separated the Earths and re-routed them to a single point to eliminate ground loops and even fitted a small Capacitor (1/4 Farad) directly to the Amp...and eliminated 95% of the Interference...then fitted the Cog Drive

The problem is probably being caused by a Ground Loop, where different Earthing points have different levels of potential (resistance).
Your biggest issue will be that Head Unit is not just grounding out by its Earth Cable, but also by it's mounting cage and any other chassis contact points. Adding the Aux Cable to the front merely amplifies the issue.

Two things to try :
1) Get an Aux-in Cable for the rear of the Unit and a suitable adaptor cable for your Ipod.
2) Find the Earth for your Head Unit's power supply and run it directly to the Battery.

Good luck

[Wyld Stallyn]

WTS^^^

Star Earth Good

Earth Loop Bad

Do check the engine bay for loose connections where the mods have taken place...

Also not all cables are equal some are not as screened as they could /should be and in some cases I've found actually wired wrong

If you think it's TOO Cheap it's probably made that way too

[H5V VE]

Thank you guys

Sounds like I am going to have to take some brave pills and yank the head unit out then.

Is the rear aux thing a std 3.5 mm jack?

[FoxdieUK]

H5V VE said:

Thank you guys

Sounds like I am going to have to take some brave pills and yank the head unit out then.

Is the rear aux thing a std 3.5 mm jack?

Nope it's a proprietary connector.

I wrote a guide on how to fit the rear aux cables (which also includes sections on how to get to the rear of the head unit and how to significantly reduce alternator hum), you can find that here;

http://is.gd/vim_cable_fitment

[snowwolf]

I use one of these, works flawlessly and produces a much better sound and eliminates any interferences, works for ages on the battery.

http://www.amazon.co.uk/Bluetooth-Receiver-Speaker...

[Z0m81e]

I always had this when charging my phone at the same time as playing music. I tried isolating the accessory socket using one of those noise suppressor type things but that had no apparent effect. What eventually cured it was putting something like the picture below between the phone and the aux socket on the head unit



I think Foxdie was the one who put me on to it. I think it was his idea I borrowed I put two phono sockets in the bottom of the arm rest cubby hole and wired them through to the aux socket through one of those and I haven't had the problem since.