Shift Interlock System
WARNING: This page is about a different car, the 2003 Ford Econoline. However, it is still accessible from the selected car via links, so may be relevant.
The shift interlock system prevents shifting from PARK unless the brake pedal is depressed. The shift interlock system consists of a shift lock actuator mounted at the base of the steering column tube. If the ignition switch is in the RUN position, the shift lock actuator is continually on unless the brake pedal is depressed.