Have you heard about the "bad caps" plague? In the IT industry we felt some effects from it. Since it affected most electronics device made between 1999 and 2007. I've seen a few motherboards made around that time go bad for some "strange" reason. I guess the BMW diversity amplifier could be a victim of it.

http://en.wikipedia.org/wiki/Capacitor_plague

 

Good write up...

Just done this today an I didn't really have anything cleaner so I just used some sand paper an used white spirit to clean the contacts an dry them but it's no any better..??!.

Did I not clean the contact properly or is mine totally buggered....??!.

 

Hello Guys,
Unfortunately, I ended up in the same boat as you ... since my FM reception is fine (not that I care about it as much), but FOB only works when I am next to rear window (close to Diversity Amp off course). All my research pointed me to this issue, however; the amp at dealer ship is about 375 USD... would like to confirm before I bite that bullet. I read so many threads, and kind of summarize all the information. It would be helpful (for me and the next victim) if anyone can answer questions below.
1. Is there a way to confirm it is diversity amp before I buy another one.
2. Anyone tried fixing this issue successfully, instead of getting a new one?
3. I took out the panels to see the amp (wanted to make sure the mhz, snapshot attached)... It only has FDB 315 written on top... assuming it means its 315 MHZ (I dont have easy access).
4. I see the following three options for the amplifire. Dealership recommended me the 2nd one, however; I guess its in my best interest to find the latest one...
a. Factory install diversity amplifier: 65 20 6 931 719 (that I have now)
b. Revision 1 diversity amplifier part no: 65 20 6 988 057 (Dealership selling me for about 375)
c. Revision 2 diversity amplifier part no: 69 20 9 193 836 (I think I should get).

Also, does it require any initialization once installed? I took out leads to older amp to test, and then put them back. However, after that, even when I lock the car, security system does not kick in...

Thanks in advance

 

Get it used. Bmrparts.com

 

should one try to clean the connectors first?

 

I just followed your DIY and ...nothing works. It's a shame to realize that I ordered a 315Mhz while my car is 868Mhz :-( I'm totally screwed

 

Can you return it and get the correct frequency module ?

 

I am in Vietnam and ordered it from Europe :-( Returning is impossible

 

Hey guys! Thanks a lot for the information. The stuff you share in these posts and knowledge you share is extremely helpful!

I bought 2008 M5 a few months ago with a hail damage, rear glass was shattered, but the interior was dry. I still assume that water got inside, because I had no sound in the car (PDC, seat belt alert, music, and etc-nothing), and my key fob (not CA) was not communicating with the car. Amplifier in the trunk that is located next to the battery where the spare tire should be had some signs of corrosion. So I put the one from 2008 525model, which didnt do the trick. Then I learned from the these forums that diversity antenna could be an issue. Again, the same 2008 525 became a donor, and I swapped the diversity antenna. Now my key fob works perfectly!!! One down! But still, I have no sound in the car, besides the music that my V10 is playing!!!
Please, advise on what could be done.
Thank you all in advance.

 

Did you try switching out the amplifier that has corrosion?