Ok, this is really bugging me, since I have had my truck, every time I turn off the truck you can hear a buzzing sound on the passengers side under the glove box. Does anyone know what this is??? Is this normal? Thanks for your help.

 

If you’ve been running the A/C, what you’re hearing might be the pressure in the system equalizing. On the passenger-side firewall under the dash is where the A/C box is