Q: What is the purpose of the Brake Transmission Shift Interlock (BTSI) system?
A: The Brake Transmission Shift Interlock (BTSI) system stops the shift lever from moving out of Park without the brake pedal pressed and the ignition key from being removed unless in Park. To remove it in early models, the center console is removed and the electrical connector unplugged. The solenoid is then pried off from the ball sockets and removed from the shift lever base. In later models, the solenoid is part of the shifter assembly. Installation is the opposite of removal.