My s320 is doing some very bizarre things

[fredsegal]

Driving along late last night I heard a sound that made me think someone was in the back seat. Freaked out I stopped quick, jumped out of the car and opened the rear door to confront the stow away. There wasn't anybody there but I could see, and hear something moving....... It turns out the passenger seat had fully reclined and was now smashing the back seat, it then started to move as far forward as possible, then back and back again. I disconnected then reconnected the door switch and was able to restore the seat to a normal position. I then disconnected the switch and thought I would address it today but as I drove to the store the seat began it's crazyness all over again. Has anyone else experienced this?