Hi fellow S2Kers,

I have a weird electrical issue with my car, and am reaching out to the community to see if anyone else may have experienced the same problem.

It started with the installation of a new head unit, door speakers, amp, and sub, at a high-end audio shop in LA. Shortly after getting the car back, I discovered that when I use the door switch to adjust the side mirrors, a very loud popping sound is emitted from the speakers. It definitely sounds like electrical interference of some kind, but we can't figure out where it's coming from. It only happens with this switch (not the power windows, power roof, etc), and the audio technician has torn the car apart trying to find a reason (has tried adding filters, which reduce the sound but don't eliminate it, has tried moving the RCA connectors, has even tried installing a new mirror switch, all to no avail). It doesn't happen when the radio is off (unsurprisingly), and the sound emanates from both speakers (not just the driver's side).

To be fair, I can't say for certain that this wasn't happening before, with the stock radio. I almost never had the stock radio on, and I also almost never adjust the side mirrors, so it's quite possible that the problem did exist (perhaps much more quietly before). Or maybe it didn't exist before because the amp is inside the factory radio (is my understanding). I talked to the previous owner of the car (a co-worker), and he didn't recall hearing this sound before, so that does suggest more strongly that it was introduced by the new stereo system. He suggested that I post here (as he had done when he owned the car) to seek out advice.

Has anyone else heard of something like this? My apologies for the lack of technical details; I'm not an electrician, and am not well-versed in the nomenclature. But any thoughts or ideas are welcome, as I can pass them along to my audio technician.

Thanks!
cleo

 

I had a similar problem with my 06 model. Whenever I would adjust the mirrors, the radio would drop power (display go blank, no sound) for a few seconds, and then come back on. It seems all or most of the power for the cockpit controls comes in through two bussways. These are each controlled by a relay located under the dash. In my case one of the relays was breaking contact (faulty). I Cant tell you which one cause I just replaced both while I was there.
Hope this helps.

 

Thanks for the reply! Unfortunately, it doesn't sound like the same problem. The audio guy who's been working on the car has already tried circumventing the existing wiring & relays in the car by running power directly from the battery to the radio or to the mirror switch, and in both cases, the noise still occurs. In my case, the radio doesn't lose power, just noise from the motor for the electric mirrors is getting picked up by the amp and coming out through the speakers.

It doesn't sound like the same issue, but I really appreciate that you responded!

 

Did they run new speaker wire into the doors?

 

Not as far as I am aware (I can call and ask). Are you thinking that new speaker wire could cause the problem, or that new wire could potentially fix it? Thanks for the reply!

 

Not sure what you/they have done already to try to narrow the problem, but I'd try to narrow down at
exactly which point the noise is entering the system.
1) does it happen with all sources (CD/am/fm)? If only radio, sounds like RF through the air
2) have you tried disconnecting the RCAs at the amp, and hooking up a source such as an MP3 player
directly to the amp, thus eliminating the headunit and RCAs from the equation?
3) finally, if that fixes the problem, I'd try using a different, good quality set of RCAs from the
headunit to the amp outside the car to determine if it's the headunit or the RCA run.

 

Yeah, unfortunately he tried these things and was not able to isolate the problem.

Thanks for the response, though. Unless someone runs across the problem themselves, and figures out a solution, I think we're pretty much just going to have to live with it. Good thing I don't need to adjust my mirrors very often.