er8086

okay guys i just got this car and it came with the sos malfunction, its 2007 530xi 100k on it, it is the wagon. The radio is a professional with the small screen no Navigation but has Satellite radio and voice control. has aux plug in rear of the center console.

So the issue, Sos malfunction everytime since i bought the car, no bluetooth, no satellite radio and no voice control. they have never worked since i bought the car.

So i started researching the most bus system and the m-ask and the Tcu and all that crap.
I bought a same number tcu "so hopefully it wouldn't have to be coded" plugged it in and nothing. so started checking the most system. So if i unplug the most port at the tcu no light coming from the most bus and no light from the tcu unless i unplug the main harness from it and plug it back in.

so next i checked the next thing which is in the drivers rear wheel well and is the umf"i think" has a pink antenna and a most bus. check it and it has light on one side.

so next place to check is in the glove box and no light at the service port when i pull it off. it had light for a second until the sos malfunction came on then nothing.

my car has provisions for a cd changer in the glove box but doesnt have the fiber optic line.
so cant check it there.

when you click on the sos button nothing happens.
when you try and turn on the bluetooth connectivity you click it but it wont check the box.
when you push the voice control button nothing at all happens
the satellite radio part is greyed out
the rear window defroster does work
the radio works fine am/fm/wb/cd/aux
so not the shark fin antenna being bad.

pretty much totally lost at this point any direction would help. i do not have any kind of coding stuff so i cant check it that way. Dont want to spend 1500 bucks taking it to the dealership on making the bluetooth work cause that all i really want.

so any help any pointers ive read 20 pages worth of threads on this forum already about sos and have not found anything like this.

thanks

seanjordan20

Have you checked to make sure your battery was good before you changed the part. How long has the battery been in the car? I would go that route first or keeping it unplugged for 15 mins.

er8086

Did that first, just forgot to put it in the first post, battery is new and i have unplugged it and let it sit for a while and no difference at all

seanjordan20

Only thing I can offer is the means to see the codes of you have them. I would suggest getting INPA and hooking a laptop up to the car.

reddv1

It has to be the most ring is broken somewhere because everything is down connected to it. Check the most connection to the mask unit. Your audio works because you have HiFi amplifier and not connected to the most ring.

Gee_115

Since you are new to these cars I think this is your best bet, look up this part, MOST bus connector/jumper 61136917541. This allows you to bypass a system. Basically you connect this at each point in the MOST system until you can tell which is not working.

From my experience with the car, a SOS usually comes from a bad TCU so I would start there. You need to code the TCU to default settings then see if the problem remains. I would also check the VIN on the M-ASK to make sure it is original to the car, otherwise it needs to be coded, voice control doesn't work if the M-ASK is not original or a replacement by dealer. In order for voice to work you would need a code from the dealer, most dealers won't even know what you are talking about they will offer you a replacement.

er8086

Thanks for the info, I am actually going to call the dealership today to order that to do a run down of my system my issue is that I can't find a flow chart or like a system chart. So after a bunch of research I know that the tcu is not it because I already changed that out and no change and I believe that the antenna for the satellite radio is bad. thats where the light stops in my most system.

er8086

Also with the m-ask not being coded to my car that actually may be a possibility because in the info screen of the bmw assist it has vehicle make model color and it's all blank.

stylinmike

For what its worth, I had an SOS malfunction error in my new M5. I read the codes and it say mayday switch led non functioning. So I looked up at the SOS switch - no light. Pulled the switch to get it replaced......the previous owner had unplugged it. Plugged her back in and its all good now. Probably not the issue you are having, but food for thought. Also, my bluetooth worked while it was unplugged, so again probably not your issue, but maybe this will help someone searching in the future.

Gee_115

Since you changed out the TCU and did not have it coded, it could still be an issue. Almost all the modules have to be coded to the car to operate with full efficiency. Maybe it is not, but you should get it coded back to default and input your vin.