Hey there guys having a slight problem that occurred recently. As I was driving home my car started to beep as if the door was open. I slowly understood that it would happen every time my car would go over bumps. I know it is for sure the door sensor (not sure if there an actual door sensor), I know this because the light would flash once very quickly.

Side notes

Mustang gt 2005
I made sure the doors were all closed.
I also turned off the car and tried again, it still occurred.

If anyone has ever experienced this what were your solutions.