bmrjay

Hey Cheryl,

My cars audio recently stopped working as well. Only the AM & FM work. Did you ever find out why your Bluetooth, AUX and USB stopped working? I also get an SOS malfunction error when starting my car. Any info would be much appreciated.

BrakeFade

I wanted to post my experience because I never could find direct answers after doing multiple google searches:


2008 550i
Has the USB and Aux port under the armrest in the center console. Last week my USB port and the Aux port both stopped working. On the Idrive screen, Aux is white and appears to be active but does nothing when selected. Bluetooth for Phone calls was still working without issue. Tried just connecting a cable to usb to charge the phone and nothing. So both ports failed. Checked all fuses behind glove box and all were ok.

Before the failure, I was able to use a Bluetooth device powered by the USB port and sending audio into the Aux port (center console).

Pulled the MULF2 High module located under the spare tire in the trunk and replaced. I now have usb and aux ports working and idrive selects AUX again.

I cross referenced the MULF2 High module part number (realoem ) in my vehicle with one I purchased off fleabay to ensure it’s interchangeable.

Hope this helps anyone who is experiencing similar symptoms (usb failed, aux port failed, Bluetooth phone worked ok).

rfctabs

Hi All,

I have an F10, 530d Saloon (Sedan) built in October2012. No major issues aside from replacement of the EGR under BMW recall.

I know this thread is old now, but I had the exact same issue and wanted to share my accidental solution.

In line with what other users on this thread reported, overnight my USB drive stopped working and the vehicle no longer saw my phone as a media device. My Samsung Galaxy S10+ did connect via Bluetooth and was fine for calls - just no media. On the iDrive, for USB and phone it just said "not connected" or some such.

I paid my local dealer £50 for diagnosis. They said it was a fault in the head unit and would cost £2,500 (!) for a replacement, including fitting and taxes. Naturally, I declined. (they also said that the USB thumb drive at 256GB was too large, even though it's been working perfectly since I got the car seven years ago!) I investigated replacing the MULF2, but was not confident of acquiring the correct part. I also didn't know how to re-code it if that was necessary. I checked the fuses but whoa - OMG! How can a car possibly need so many fuses? Two fuse boards, one barely accessible! So - no music!

I remembered that the car has a CD/DVD in the dash, which I never use. I thought maybe that would be better than nothing, even if it felt like going back to the noughties . I dug out a CD and popped it in the dash and the CD played, but... also, to my amazement, the USB and phone as a media device came back on line and worked perfectly. That was two months ago, and they've been fine ever since.

So, if you have this problem in your car, try a CD in the dash, just in case.

Cheers,

Peter

Dark Vader

On the first of this month (September 2022) I picked up a 2010 E60 535i... I have the SOS malfunction error, and my BT won't populate on my phone during pairing, and my USB/AUX don't work... I'm assuming I can either find a new component on eBay or fiber loop it out... I have the fiber loop, but I don't know where my components are... are they under the spare or are they behind the rear driver-side panel? I'd like to get an idea before I start talking things apart... also... any idea which component it might be considering I'm having these specific errors (I have FM/AM/WB working and AUX in on my screen but when I select it, the screen button shows I'm pressing but the screen doesn't;'t change (MULF2 maybe... if so... where is it in my car/my year/my model)

I'd like to work on this tomorrow 9/11/2022 so hopefully, someone will chime in by then

thanks!!!

seanjordan20

Depends if it's been relocated. Usually behind the left wall at this point but it doesn't take much to lift the spare tire area to ensure the needed components has been relocated. If you're getting the SOS light then I'm assuming the mulf2. I take it you don't have ISTA and that would let you know for sure

Dark Vader

I do not, but if it's a necessity to have in my arsenal, I shall acquire it

seanjordan20

I would definitely get it if you plane on working on modules.

Dark Vader

so I replaced the completely corroded MULF2 unit with one I got from eBay that had matching numbers… my BT/AUX works fine now!! My iPhone is coming up as an incompatible USB device… not happy about that… I like using Apple Music/Pandora/SiriusXM

I guess I just have to use the AUX cable (Which works fine)

seanjordan20

Glad to hear you got it back working