When you are in your car running and it is quiet, ( no radio, talking etc) every time you step all the way down on the break pedal you can here a electronic sound. Does not matter what gear I m in.... I assume it normal and part of the drive/neutral system this car has.
my car makes all these above sounds. I m sure it s normal. Last time I was at the Merc Benz dealer I was speaking to one of the techs who said they get lots of these inquiries because of all the lastest equipment on new cars. One of the sounds being heard could be part of the fuel tank vapor system which I believe can no longer just be vented into the air like in the olden days. Some of these items cycle een when the car is firsy shut down. Maybe someone can back up my information when they go to the dealer.