Here is audio of sounds made by Bolt EV after level 2 charging. The charging from 60% to 80% was done in a garage with temperature of 85 F and after driving ~50 miles on day where high temperature was ~80 F. This sound is routine for my car during summer as most days in Raleigh area are 80's-90's and the car routinely is charged after a 35-50 mile drive. In other words, I hear this sound after the car finishes charging regularly.
The first 5 minutes of the recording is fairly loud and the remaining 5 minutes is pretty quiet. The sound is a little louder than normal as I had the hood up for most of the time but it is still loud enough to notice even with hood closed.
If your Bolt is making this noise after charging, I would consider it likely normal and you should leave it plugged in as it is cooling the battery and other components after the charge.
The first 5 minutes of the recording is fairly loud and the remaining 5 minutes is pretty quiet. The sound is a little louder than normal as I had the hood up for most of the time but it is still loud enough to notice even with hood closed.
If your Bolt is making this noise after charging, I would consider it likely normal and you should leave it plugged in as it is cooling the battery and other components after the charge.