Download Owner's Manual - RHD (UK, Australia)
With Automatic Transmission/ Dual Clutch Transmission: To turn off the engine (START/RUN position) or vehicle power (ON position), press the ENGINE START/ STOP button with the shift lever in the P (Park) position. When you press the ENGINE START/STOP button without the shift lever in the P (Park) position, the ENGINE START/ STOP button will not change to the OFF position but to the ACC position. Also, the steering wheel locks when the ENGINE START/STOP button is in the OFF position to protect you against theft.
It locks when the door is opened.