[ctuna]

How can you tell if your combox is working without sound?

I would poke around in the amp area see if the fan is turning
check fuses. You need to positively identify your system you
could have got any of the three system in that year in the US.
Base system with no amp was issued from 2010 to 2011.5 build.
I don't know if the L7 was standard issue for the 335is or not.

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.bmwmotorsports.org/pdf/e7...%20Systems.pdf
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.bmwmotorsports.org/BMW_docs/mostbus.pdf
http://www.e90post.com/forums/attach...4&d=1278871872