A few weeks ago, I started getting a "SOS malfunction" message upon starting my car. The first time I got the message, my hard-wired radar detector was left on and plugged in, so it powered on when I turned on the car. I thought that maybe because I may have tapped into the SOS button wire, it caused some interference with the system. Though, this has never happened in the 4 years that I've had it hard-wired. Another coincidence is that as I was driving out of the parking lot, I had noticed that the SOS button had also popped out of place, so I pushed it back in. The light went away after a while of driving so I thought everything was ok. However, I continue to get the message a few seconds after I first turn on the car after it has been parked for a while. It does not always appear if I had the car off for only a short period of time.

I've read a few posts on various forums about this, and there seems to be a wide variety of reasons this light can appear. It also seems to occur in 1-series and 3-series as well. In my case, the iDrive is still functional, and so is the stereo. The only thing
that does not work until the message goes away, is bluetooth connection with my phone. The message does not seem to ever display if I leave the bluetooth function disabled in iDrive. I have to test this theory more.

I'm really hoping it's not a TCU issue or a precursor to something even worse. I currently have about 58k miles on the odometer, and something tells me that the BMW "gold" extended warranty will not cover any related components (just my freakin luck!). Though the gold plan does indicate that it covers electrical, inclujding "all gauges; instrument and service indicator circuit boards; LCD display modules and coding plugs; control modules." The "plantinum" plan in addition covers iDrive, cd/radio, and nave...not sure if TCU is considered part of that or not.

Anyone else have experience with this?

 

my TCU is bad. TCU definitely contains bluetooth, also voice rec in some models, I believe.

check your cables inside the left trunk liner. should be 4 going into top of TCU and one big connector on bottom. could be loose. also one guy on here said the green wires in spool mounted above TCU were loose causing intermittent issues and he had to glue them in place. said he lost TCU every time he went over a bump.

sounds like you have a loose cable or connection somewhere. if you have fiber optic beam shining out of at least one of the cables (i believe its only one, could be more) when you pull them out of top of TCU, then your MOST loop is intact and it probably is an intermittent fault in the TCU

 

Thanks for your suggestion, I will check the connections. This has started happening a month after I had the rear bulb lamp carrier recall performed. Not sure if it's coincidence or something was knocked loose when the work was done. It is strange that the malfunction light disappears after a few minutes of driving and bluetooth connection to phone is restored with no problem.