I read that MB came out with the "smart key" in 1997. If this is true what key was used on the 1996 e320? Does the 1996 have the smart key...with the "window down" feature or is it some other key?? Thanks for the help!

 

Das keys with the infrared were 97 up,96 had a blade key no conversion possible since it did not operate on the can bus system.
http://w210.pietrzyk.net/electrical_80_97changes.htm
98 went to the even more advanced system.
ohlord