What Is Grade Assist
Provides additional grade braking with a combination of engine motoring and high-voltage battery charging to help maintain vehicle speed when descending a grade.
Switching Grade Assist On and Off
Press the grade assist button to activate grade assist. The grade assist lamp appears in the instrument cluster. Press the button again to switch it off.
Your vehicle determines the amount of engine motoring and high-voltage battery charging. You could notice the engine speed increasing and decreasing to help maintain your vehicle speed when descending a slope.
Grade Assist Indicators

Automatic Return to Park (P)
Manual Park Release - Gasoline. Automatic Transmission Audible Warnings
Switching the Ignition Off
When the ignition is on or in accessory mode, press the push button ignition switch once without your foot on the brake pedal.