You need a new navi disc. The updates are on the disc. When you insert the new disc, check the date on the disc you have and the new one. If you get a new disc, the screen should show you its uploading new software. If not the disc is not newer than what you have. The updates are on the disc only and you cannot do it any other way.
if you are talking about the 1997 slk 230 or 320 then no there is not. However there is a CD changer usually located in the trunk, but that was an upgrade
The 2007 Mercedes-Benz CL-Class has a drag coefficient of 0.27 Cd.
The 2008 Mercedes-Benz M-Class has a drag coefficient of 0.34 Cd.
The 2012 Mercedes-Benz E-Class has a drag coefficient of 0.27 Cd.
The 2013 Mercedes-Benz C-Class has a drag coefficient of 0.27 Cd.
The 2002 Mercedes-Benz SL-Class has a drag coefficient of .32 Cd.
The 2005 Mercedes-Benz SL-Class has a drag coefficient of .29 Cd.
The 2014 Mercedes-Benz E-Class has a drag coefficient of 0.28 Cd.
The 2004 Mercedes-Benz C-Class has a drag coefficient of .29 Cd.
The 2011 Mercedes-Benz M-Class has a drag coefficient of 0.34 Cd.
The 2013 Mercedes-Benz E-Class has a drag coefficient of 0.27 Cd.
The 2009 Mercedes-Benz S-Class has a drag coefficient of 0.26 Cd.