Shift Interlock: Description and Operation

Brake Shift Interlock System
The shift interlock system prevents shifting the transmission out of the PARK position unless the brake pedal is depressed. The shift interlock system consists of a shift lock actuator mounted on the ignition switch. The actuator is energized when the ignition switch is turned to RUN, locking the transmission range selector lever in the PARK position. When the brake pedal is applied and the Brake Pedal Position (BPP) switch activated, the shift lock actuator is deactivated, allowing the selector lever to move out of the PARK position.

The ignition shift interlock cable locks the selector lever in the PARK position when the ignition switch is in the lock position. It also requires the selector lever to be in the PARK position in order to turn the ignition switch to the lock position.