Ignition Key Inhibit

WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

The ignition key cylinder inhibit feature prevents the ignition lock cylinder from being rotated to the OFF/LOCK position when the vehicle is not in PARK.

The key removal inhibit solenoid (part of the ignition switch) receives battery voltage at all times from the BCM fuse 18 (5A). The ground control circuit for the key removal inhibit solenoid is routed to a park detect switch within the brake shift interlock actuator.

The park detect switch routes the signal directly to ground to activate the ignition key inhibit solenoid.

When the selector lever is in PARK, the brake shift interlock actuator is open, preventing the solenoid from actuating. When the selector lever is moved out of PARK, the switch closes and completes the circuit to ground.

When the selector lever is in PARK, the key removal inhibit solenoid deactivates and allows the ignition lock cylinder to be turned to the OFF/LOCK position to remove the key.