Electrical buzz related to level of dash illumination

[craufurd]

Hi all

I have a 2010 e82 125i N52, non-iDrive, with standard BMW Professional stereo. I have been trying to diagnose a constant high pitch electrical buzzing noise coming from an unknown source - possibly speakers but maybe not - it sort of comes from everywhere and nowhere at the same time.

This noise only comes on with the key fob inserted. It is the same pitch regardless of speed, any other electrical function, time of day, you name it.

In any case today I discovered that it is directly corelated to the level of dash illumination. If i set illumination at the lowest, the sound disapperars, highest it gets louder.

Now I am happy to live with that, but wondered if anyone has had a similar issue and if so how you resolved it.

Could it be a bad LED somewhere on the illumination circuit?

Regards
Geoff

[craufurd]

OK, I have narrowed this down. It is coming through the speakers and definately related to the illumination settings overall which drive the illumination level on the stereo screen.

As such I am thinking to swap out the existing bmw professional stereo for a replacement, identical model. One qustion is does a replacement factory stereo require dealer coding and are there any other considerations to be aware of before I embark on this course of action?

[reisf]

Originally Posted by craufurd

OK, I have narrowed this down. It is coming through the speakers and definately related to the illumination settings overall which drive the illumination level on the stereo screen.

As such I am thinking to swap out the existing bmw professional stereo for a replacement, identical model. One qustion is does a replacement factory stereo require dealer coding and are there any other considerations to be aware of before I embark on this course of action?

Yes it might require coding. If you're going to replace the head unit do not replace it with a used one as the screen on the professional radio is prone to failure. If you need help with coding after the replacement send me a PM

[craufurd]

Cheers thanks very much for that