SOS phone LIGHT ON, everything works: annoying

bigtakeover · 05-06-2019, 08:01 PM

2008 e91 wagon, SOS light is on the dash, all chimes, aux input, radio working as usual, but... there's a slight hiss sound coming through the speakers at all times (kinda like listening to an old record) this sound goes on with out the key in the ignition... any ideas on how to fix this?

do I need an exorcism?

ctuna · 05-06-2019, 08:47 PM

bigtakeover · 07-09-2019, 05:42 PM

after TONS of research, the SOS code ended up being a relatively simple fix. The satellite radio receivers tend to go bad, thus being a dead zone in the loop of the fiberoptic MOST system. I found this little plug-in loop to bypass the satellite radio box in the trunk of my e91 (under the floor) https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
why was this info so hard to find? i dunno, but hopefully you find this post soon in your search of how to fix the SOS code. photo below - right click and open in new tab if it's not showing up

dpaul · 07-09-2019, 07:08 PM

An open MOST fiber optic or receiver/transmitter fault in any module on the MOST ring would invariably generate fault codes.

I suggest that you download the freely available BMW diagnostic software (BMW Standard Tools - Bimmergeeks.com) and buy a $45 DCAN cable. If you had done this, you'd have discovered the source of your problem immediately, without having to do TONS of research and guessing.

First thing to do with any problem, particularly electrical ones, is check for codes.

05-06-2019, 08:01 PM	#1
bigtakeover New Member 0 Rep 7 Posts Drives: 2008 328xi wagon Join Date: May 2019 Location: los angeles iTrader: (0)	SOS phone LIGHT ON, everything works: annoying 2008 e91 wagon, SOS light is on the dash, all chimes, aux input, radio working as usual, but... there's a slight hiss sound coming through the speakers at all times (kinda like listening to an old record) this sound goes on with out the key in the ignition... any ideas on how to fix this? do I need an exorcism?
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05-06-2019, 08:47 PM	#2
ctuna Lieutenant General 1911 Rep 13,103 Posts Drives: 325xi 06 wagon MT Join Date: Jan 2010 Location: Santa Cruz, Ca iTrader: (0)	First of all you must understand the Radio is never really off. The radio in most models is used for the chimes. So when you turn the radio off only the display is off. Sos error means your TCU or Mulf has gone bad in most cases. Sos in the US is no longer supported because its 2g and there is no more 2g. But that module also runs the Hands Free Bluetooth Phone if you have that option. Hiss is most often caused by a bad head unit in the case of the PRO Radio. If you lock the car the hiss will go away faster as the car goes to sleep faster. electical e90 pdf http://www.google.com/url?sa=t&rct=j...,d.cGU&cad=rja http://www.google.com/url?sa=t&rct=j...85464276,d.cGU http://www.google.com/url?sa=t&rct=j...85464276,d.cGU BMW stereo types http://www.e90post.com/forums/showthread.php?t=352586 http://www.e90post.com/forums/attach...2&d=1266451970 http://www.e90post.com/forums/attach...2&d=1260829447 http://www.e90post.com/forums/showthread.php?t=343673 http://www.e90post.com/forums/showthread.php?t=138949 http://www.e90post.com/forums/attach...1&d=1209780605 http://www.e90post.com/forums/attach...1&d=1209780865 http://www.e90post.com/forums/showthread.php?t=641323 http://bmwcoders.com/forum/3-er-8/bm...1-e92-e93-291/ http://technicpnp.com/menuDiagrams/d...e90_92_93.html http://www.musicarnw.com/page-2/ http://www.e90post.com/forums/attach...3&d=1169133185 http://www.e90post.com/forums/attach...4&d=1278871872 http://www.e90post.com/forums/showthread.php?t=1036190 Last edited by ctuna; 05-06-2019 at 08:56 PM..
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07-09-2019, 05:42 PM	#3
bigtakeover New Member 0 Rep 7 Posts Drives: 2008 328xi wagon Join Date: May 2019 Location: los angeles iTrader: (0)	after TONS of research, the SOS code ended up being a relatively simple fix. The satellite radio receivers tend to go bad, thus being a dead zone in the loop of the fiberoptic MOST system. I found this little plug-in loop to bypass the satellite radio box in the trunk of my e91 (under the floor) https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1 why was this info so hard to find? i dunno, but hopefully you find this post soon in your search of how to fix the SOS code. photo below - right click and open in new tab if it's not showing up
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07-09-2019, 07:08 PM	#4
dpaul Lieutenant Colonel 654 Rep 1,893 Posts Drives: 2009 E90 335xi, 2011 E93 M3 Join Date: Dec 2012 Location: Boston iTrader: (3)	An open MOST fiber optic or receiver/transmitter fault in any module on the MOST ring would invariably generate fault codes. I suggest that you download the freely available BMW diagnostic software (BMW Standard Tools - Bimmergeeks.com) and buy a $45 DCAN cable. If you had done this, you'd have discovered the source of your problem immediately, without having to do TONS of research and guessing. First thing to do with any problem, particularly electrical ones, is check for codes.
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