SMD Keyfob Signal Interference

Printed From: the12volt.com
Forum Name: Lights, Neon, LEDs, HIDs
Forum Discription: Under Car Lighting, Strobe Lights, Fog Lights, Headlights, HIDs, DRL, Tail Lights, Brake Lights, Dashboard Lights, WigWag, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=145652
Printed Date: April 26, 2024 at 8:08 AM

Topic: SMD Keyfob Signal Interference

Posted By: larbel
Subject: SMD Keyfob Signal Interference
Date Posted: September 27, 2019 at 8:00 AM

Hi guys... I'm trying to add some ambient lighting to my Audi 8V, I'm using OEM VW SMDs for the purpose and running the wires as illustrated in the picture. It's hooked up to an ambient light wire and ground, but it created some EMI/RFI interference with the keyfob, I literally have to stand within inches to the car before I could lock and unlock the door, it doesn't really matter if I hook them up with other wires or ground, still the same result, but if I hook them up to external power than it's all fine so I guess the SMD isn't the fault here and it's the wires or the length of the wires? I've since added 4 small ferrite beads to the wires, it helped a little but still working very intermediate.. Can someone please help and see what else can be done to fix this? Thanks!!

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Replies:

Posted By: geepherder
Date Posted: September 27, 2019 at 9:09 AM

I'm guessing by your picture that power is connected in the passenger kick panel, right? You mentioned you tried other wires, but were they in other locations, or the same general area? Have you tried moving it to the center console, or the driver's side?

Are you using a factory ground location? If so, is that shared with the keyless module or something related?

If none of that makes a difference, you could try a DC-DC converter to try and provide a cleaner power source (since external power worked).

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My ex once told me I have a perfect face for radio.

Posted By: larbel
Date Posted: September 27, 2019 at 10:20 AM

Thanks!! Ya, all I’ve tried are the wires from the same general area, will try the center console and driver side tomorrow!!!

Posted By: larbel
Date Posted: September 28, 2019 at 11:36 AM

geepherder wrote:

I'm guessing by your picture that power is connected in the passenger kick panel, right? You mentioned you tried other wires, but were they in other locations, or the same general area? Have you tried moving it to the center console, or the driver's side?

Are you using a factory ground location? If so, is that shared with the keyless module or something related?

If none of that makes a difference, you could try a DC-DC converter to try and provide a cleaner power source (since external power worked).

Hmm... I tried both tapping them into center console area power/gound and driver side power/ground.. Still getting interference, does this mean it's more coming from the SMD itself? And if I want to try DC-DC converter, do you have any recommendation? Or would and 12V dc to 12V dc converter/regulator works? I've supposed wrapping the SMD itself with tinfoil wouldn't help either? Thanks!!

Posted By: geepherder
Date Posted: September 28, 2019 at 11:51 AM

It was worth trying. If you power the SMD's externally and have no noise, that tells me they are not the source of noise.

I don't have recommendations on a DC-DC converter (I've never had to use one), but you want a regulated output, so it should be clean. However, this clean power costs efficiency, so keep that in mind.

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My ex once told me I have a perfect face for radio.