I have a 2003 Screw and for the past 2 months I have been having a really weird sound in my fuse box. I replaced the relay that was making the buzzing sound and that wasn't it. The buzzing only happens randomly and it only happens when in drive or reverse. When the buzzing is going on the windows don't work and either does the garage opener or sometimes the windshield wipers. When I took the relay out the sound went away. It's really confusing and I have no idea what it could be...

 

Check both coil poles with a DVM. WITH THE RELAY OUT One side should be the switched power to the coil the other should be ground. The buzzing is the coil being energized and de-energized very quickly. You either have a faulting switch somewhere or (more likely) a bad ground