The Issue got resolved. The Issue was that there was a loose connection with the wire connecting to 12V battery, once that is fixed its working fine. Thank you all for taking your time in trying to help.
I was out of town for a month and My 2015 Nissan Leaf was not used during this period.
Since i returned back two days back, As soon as i go somewhere and turnoff the car, it starts making some buzz sound for a minute or so and this sound stops.
As soon as the car starts making this noise since...