All Mercedes have a key fob in the dash.
If you want keyless go they just put a silver button in the ignition slot. It is literally a removable button that replaces the key. The entire setup is a joke!
If you want to piss off a Mercedes owner walk off with his start button!
2014 ///M5 Individual Frozen Grey, Silverstone Full Merino, Piano Black, Exec Pkg, Drivers assistance plus, LED Pkg, Bang and Olufsen, 20" 343M Forged Alloy Wheels
Countermeasures: Bel StiR+, Laser Interceptor Quad HP, Zaon MRX
Upgrades: Eisenmann Sport with M Performance Carbon tips, Dinan anti-roll bars