Shift Interlock System: Description
WARNING: This page is about a different car, the 2004 Chrysler Pacifica. However, it is still accessible from the selected car via links, so may be relevant.
The Brake Transmission Shifter/Ignition Interlock (BTSI) is a cable and solenoid operated system that prevents the transmission gear shifter from being moved out of PARK without a driver in place.
Refer to the following chart that expected shifter response, depending on ignition key/switch (Fig 1) and brake pedal positions.