How to turn off alarm on mercedes?

Usually, the quickest way to turn off an alarm on most year model Mercedes vehicles is simply to hit the switch on Your key FOB. Simple, but true! I'm going to go ahead and assume You've already tried that, or don't have Your remote entry handy. Another way You can get the alarm to stop (and maybe also get the glares people are giving You because of the horns and lights just going off!) is to use the physical key to lock and then unlock the driver's side door. This seems simplistic, but what happens is that many keys have an RFID chip in them that, when in proximity to the vehicle, deactivates the alarm when used to lock and unlock it. (The ECU gets the message that You're not a car thief. At least, You're not stealing Your own car.) Finally, if the alarm keeps going, check if You've accidentally hit the panic button --- if You haven't, hitting it now isn't going to make any more noise than the car already is!