A coil at a first location in magnetic communication with a door of a
vehicle generates a magnetic field responsive to a time varying signal
applied thereto. The first location and the coil are adapted so that the
magnetic field is influenced by an opening state of the door, and by a
crash involving the door. A signal is generated from the coil responsive
to the time-varying signal and to the magnetic field, wherein the signal
provides for sensing an opening state of the door and for sensing a crash
involving the door.