[MochiEater]

It's not the key, the ignition shuts off when the driver's door is opened and the seatbelt unbuckled. There are 2 ways to keep the X5 40e ignition on and exit with the key:

With the car ignition on, car in Park and Parking Brake on:

1) Without opening the driver's door, unbuckle the seat belt. Route the belt behind your back and plug it back into the receptacle. Leave the seatbelt buckled. Driver can open the driver's door and exit the car with the key. The car ignition will stay on in hybrid mode. The car can be driven away or put in Neutral without the key inside.

2) Without opening the driver's door, press the accelerator pedal. The ICE will start up. Driver can unbuckle the seatbelt and open the driver's door and exit the car with the keys. The car ignition and ICE will stay on. The car can be driven away or put in Neutral without the key inside.

This is also how the car can be handed off to an auto car wash attendant so they can put it in Neutral to ride the conveyor. If either 1 or 2 is not performed, when the driver exits the car, the ignition will automatically switch off and the car will automatically shift into Park (whether the key is inside or outside the car) and potentially jam the conveyor.