Brake Transmission Shift Interlock Mechanism
WARNING: This page is about a different car, the 2008 Dodge Magnum, 2008 Dodge Charger, and 2008 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.
The Brake Transmission Shifter/Ignition Interlock (BTSI) is a electronically operated system that prevents the transmission gear shifter from being moved out of PARK without the proper driver inputs. The system also contains a solenoid that is integral to the shifter assembly.
A BTSI override (2) is provided on the inside of the shifter mechanism (1) to allow the vehicle to be shifted out of PARK in the event of an electrical failure.