[Infidel]

Sorry if this has been discussed before and I just did a poor job searching, but I did my best to try and find this issue elsewhere and didnt find anything.

So the issue is, all the sudden my radio (FM, AM) has terrible reception. Stations that I used to get crystal clear are now mostly static, not able to be listened to.

What I find particularly perplexing about this issue is that as soon as I park the car and hit the start/stop button (turning off the car), the radio is instantly clear. So I figured maybe alternator or something, but then with the car off the radio is perfect until I hit the start stop button just once to turn the power on (car still not running). So clearly not an alternator issue.
Then I read somewhere that it could be LED license plate lights... Eureka! I just replaced my stock incandescent with some cheap led bulbs I got on ebay, has to be the culprit right?

I get in the car, put the key in the ignition, radio sounds perfect. Press the button to put the ignition in the on position (engine still off) and it immediately sounds static. Turn the light switch position to OFF so all exterior lights are off, still sounds static with no change. Soooo not the license plate lights I guess?

Kind of grasping at straws now, any ideas fellas?


edit: this is a non-idrive, top hifi system if that makes any distinction.

[ctuna]

Start measuring the voltage in each condition.

[Infidel]

Originally Posted by ctuna

Start measuring the voltage in each condition.

I'm a little thick, is there any way you could elaborate on that?

Is it possible that its getting too much voltage when I turn the ignition on? If it was too little I would think when the ignition was off it would be worse.

Is the powered antennae only turned on when you turn on the ignition, maybe thats the issue, and when it is not powered I dont hear its interference, Idk.

Where would I measure voltage and of what?

[ctuna]

With the ignition off it checks the battery
With the radio on and ignition on it checks the battery under
that load .
With it idling it checks the alternator at idle.

Also since you mentioned you changed the lights and you thought
it might be cause noise can you turn them off or unplug them and see
if it makes a change.

Or you can also access the 12 Volt line at the OBD terminal.
There is a list of hidden commands that allow you to display the voltage to.

http://e90.wetpaint.com/page/BC+hidden+menus

http://www.bimmerboard.com/forums/posts/876857

[Infidel]

Sorry to Necro!

SOLUTION TO THE PROBLEM:

in the center console I had a usb car charger for my phone plugged into the 12v. Apparently it was cheap POS and had very poor shielding. As soon as I unplugged and replaced it the issue disappeared